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Barboza PS, Shively RD, Thompson DP. Robust Responses of Female Caribou to Changes in Food Supply. ECOLOGICAL AND EVOLUTIONARY PHYSIOLOGY 2024; 97:29-52. [PMID: 38717369 DOI: 10.1086/729668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2024]
Abstract
AbstractUngulates can respond to changes in food supply by altering foraging behavior, digestive function, and metabolism. A multifaceted response to an environmental change is considered robust. Short seasons of plant growth make herbivores sensitive to changes in food supply because maintenance and production must be accomplished in less time with fewer options in a more fragile response. Caribou live at high latitudes where short summers constrain their response to changes in food supply. We measured the ability of female caribou to resist and tolerate changes in the quality and quantity of their food supply during winter and summer. Caribou resisted changes in food abundance and quality by changing food intake and physical activity with changes in daily temperature within each season. Peak food intake rose by 134% from winter pregnancy to summer lactation (98 vs. 229 g kg-0.75 d-1), as digestible requirements to maintain the body increased by 85% for energy (1,164 vs. 2,155 kJ kg-0.75 d-1) and by 266% for N (0.79 vs. 2.89 g N kg-0.75 d-1). Caribou required a diet with a digestible content of 12 kJ g-1 and 0.8% N in pregnancy, 18 kJ g-1 and 1.9% N in early lactation, and 11 kJ g-1 and 1.2% N in late lactation, which corresponds with the phenology of the wild diet. Female caribou tolerated restriction of ad lib. food intake to 58% of their energy requirement (680 vs. 1,164 kJ kg-0.75 d-1) during winter pregnancy and to 84% of their energy requirement (1,814 vs. 2,155 kJ kg-0.75 d-1) during summer lactation without a change in stress level, as indicated by fecal corticosterone concentration. Conversely, caribou can respond to increased availability of food with a spare capacity to process digestible energy and N at 123% (2,642 vs. 2,155 kJ kg-0.75 d-1) and 145% (4.20 vs. 2.89 g N kg-0.75 d-1) of those respective requirements during lactation. Robust responses to changes in food supply allow caribou to sustain reproduction, which would buffer demographic response. However, herds may decline when thresholds of behavioral resistance and physiological tolerance are frequently exceeded. Therefore, the challenge for managing declining populations of caribou and other robust species is to identify declines in robustness before their response becomes fragile.
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Estimation of the intake capacity of Lacaune dairy ewes at maintenance. Small Rumin Res 2022. [DOI: 10.1016/j.smallrumres.2022.106862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Dardente H, Lomet D, Desmarchais A, Téteau O, Lasserre O, Gonzalez AA, Dubois E, Beltramo M, Elis S. Impact of food restriction on the medio-basal hypothalamus of intact ewes as revealed by a large-scale transcriptomics study. J Neuroendocrinol 2022; 34:e13198. [PMID: 36168278 DOI: 10.1111/jne.13198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/25/2022] [Accepted: 08/28/2022] [Indexed: 11/27/2022]
Abstract
In mammals, the medio-basal hypothalamus (MBH) integrates photoperiodic and food-related cues to ensure timely phasing of physiological functions, including seasonal reproduction. The current human epidemics of obesity and associated reproductive disorders exemplifies the tight link between metabolism and reproduction. Yet, how food-related cues impact breeding at the level of the MBH remains unclear. In this respect, the sheep, which is a large diurnal mammal with a marked dual photoperiodic/metabolic control of seasonal breeding, is a relevant model. Here, we present a large-scale study in ewes (n = 120), which investigated the impact of food restriction (FRes) on the MBH transcriptome using unbiased RNAseq, followed by RT-qPCR. Few genes (~100) were impacted by FRes and the transcriptional impact was very modest (<2-fold increase or < 50% decrease for most genes). As anticipated, FRes increased expression of Npy/AgRP/LepR and decreased expression of Pomc/Cartpt, while Kiss1 expression was not impacted. Of particular interest, Eya3, Nmu and Dio2, genes involved in photoperiodic decoding within the MBH, were also affected by FRes. Finally, we also identified a handful of genes not known to be regulated by food-related cues (e.g., RNase6, HspA6, Arrdc2). In conclusion, our transcriptomics study provides insights into the impact of metabolism on the MBH in sheep, which may be relevant to human, and identifies possible molecular links between metabolism and (seasonal) reproduction.
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Affiliation(s)
- Hugues Dardente
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| | - Didier Lomet
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| | | | - Ophélie Téteau
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
| | | | - Anne-Alicia Gonzalez
- MGX-Montpellier GenomiX, Université Montpellier, CNRS, INSERM, Montpellier, France
| | - Emeric Dubois
- MGX-Montpellier GenomiX, Université Montpellier, CNRS, INSERM, Montpellier, France
| | | | - Sébastien Elis
- CNRS, IFCE, INRAE, Université de Tours, PRC, Nouzilly, France
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Ramirez AVG, Filho DR, de Sá LBPC. Melatonin and its Relationships with Diabetes and Obesity: A Literature Review. Curr Diabetes Rev 2021; 17:e072620184137. [PMID: 32718296 DOI: 10.2174/1573399816666200727102357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 07/13/2020] [Accepted: 07/15/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Obesity is an important clinical entity, causing many public health issues. Around two billion people in the world are overweight and obese. Almost 40% of American adults are obese and Brazil has about 18 million obese people. Nowadays, 415 million people have diabetes, around 1 in every 11 adults. These numbers will rise to 650 million people within 20 years. Melatonin shows a positive profile on the regulation of the metabolism of the human body. OBJECTIVE This study aimed to carry out a broad narrative review of the metabolic profile and associations between melatonin, diabetes and obesity. METHODS Article reviews, systematic reviews, prospective studies, retrospective studies, randomized, double-blind, and placebo-controlled trials in humans recently published were selected and analyzed. A total of 368 articles were collated and submitted to the eligibility analysis. Subsequently, 215 studies were selected to compose the content part of the paper, and 153 studies composed the narrative review. RESULTS Studies suggest a possible role of melatonin in metabolic diseases such as obesity, T2DM and metabolic syndrome. Intervention studies using this hormone in metabolic diseases are still unclear regarding the possible benefit of it. There is so far no consensus about the possible role of melatonin as an adjuvant in the treatment of metabolic diseases. More studies are necessary to define possible risks and benefits of melatonin as a therapeutic agent.
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Affiliation(s)
- Ana V G Ramirez
- Clinic Ana Valeria (CAV)- Clinic of Nutrition and Health Science, Street Antônio José Martins Filho, 300, Sao Jose do Rio Preto SP, 15092-230, Brazil
| | - Durval R Filho
- Associacao Brasileira de Nutrologia (ABRAN)/Brazilian Association of Nutrology, Catanduva/SP, Rua Belo Horizonte, 909 - Centro, Catanduva SP, Brazil
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Fernandez-Turren G, Repetto JL, Arroyo JM, Pérez-Ruchel A, Cajarville C. Lamb Fattening Under Intensive Pasture-Based Systems: A Review. Animals (Basel) 2020; 10:E382. [PMID: 32120943 PMCID: PMC7143110 DOI: 10.3390/ani10030382] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/13/2020] [Accepted: 02/14/2020] [Indexed: 12/04/2022] Open
Abstract
The benefits of pasture-based systems on the fatty acid composition of sheep meat appear to be achievable despite variability in the quality of the pastures. Lambs fed high levels of temperate pastures have an excess of N-ammonia derived from protein degradation. Furthermore, animal performance is highly variable depending on the quality of the pasture at the time of grazing, and high animal performance in these systems appears to be linked to the use of high-quality pastures with high availability, and is possibly added to by the inclusion of concentrates that allow increasing energy intake and a better use of the N in the pasture. The combination of high-quality pastures and total mixed ration offers a good alternative to the inclusion of concentrates in the diet, improving the use of N, and avoiding acidosis problems. However, information to determine the effect of a number of nutritional strategies on meat quality, and the minimum level of pasture intake necessary to achieve the benefits of pastoral systems is still lacking.
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Affiliation(s)
- Gonzalo Fernandez-Turren
- Departamento de Producción Animal, IPAV, Facultad de Veterinaria, Universidad de la República, Ruta 1 km 42,5 km, San José 80100, Uruguay; (J.L.R.); (J.M.A.); (A.P.-R.); (C.C.)
| | - José L. Repetto
- Departamento de Producción Animal, IPAV, Facultad de Veterinaria, Universidad de la República, Ruta 1 km 42,5 km, San José 80100, Uruguay; (J.L.R.); (J.M.A.); (A.P.-R.); (C.C.)
| | - José M. Arroyo
- Departamento de Producción Animal, IPAV, Facultad de Veterinaria, Universidad de la República, Ruta 1 km 42,5 km, San José 80100, Uruguay; (J.L.R.); (J.M.A.); (A.P.-R.); (C.C.)
- Programa Nacional de Investigación en Pasturas y Forrajes, Instituto Nacional de Investigación Agropecuaria, La Estanzuela 70002, Colonia, Uruguay
| | - Analía Pérez-Ruchel
- Departamento de Producción Animal, IPAV, Facultad de Veterinaria, Universidad de la República, Ruta 1 km 42,5 km, San José 80100, Uruguay; (J.L.R.); (J.M.A.); (A.P.-R.); (C.C.)
| | - Cecilia Cajarville
- Departamento de Producción Animal, IPAV, Facultad de Veterinaria, Universidad de la República, Ruta 1 km 42,5 km, San José 80100, Uruguay; (J.L.R.); (J.M.A.); (A.P.-R.); (C.C.)
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Phenotypic plasticity following weaning: winter body mass trends and food intake in relation to temperature by an arctic ungulate. Polar Biol 2020. [DOI: 10.1007/s00300-020-02623-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Tyler NJC, Gregorini P, Parker KL, Hazlerigg DG. Animal responses to environmental variation: physiological mechanisms in ecological models of performance in deer (Cervidae). ANIMAL PRODUCTION SCIENCE 2020. [DOI: 10.1071/an19418] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Context
Proper assessment of the consequences of environmental variation on animals depends on our ability to predict how they will perform under different circumstances. This requires two kinds of information. We need to know which environmental factors influence animal performance and their mode of action, i.e. whether a given factor acts alone or through interaction with other factors, directly or indirectly, instantaneously or after a delay and so on. This essentially correlative process falls within the domain of ecology. We also need to know what determines the direction, amplitude and limits of animal responses to environmental variation and change. This essentially experimental process falls within the domain of physiology. Physiological mechanisms are frequently poorly integrated within the correlative framework of ecological models. This is evident where programmed responses are attributed to environmental forcing and where the effect of environmental factors is evaluated without reference to the physiological state and regulatory capacity of the animal on which they act.
Aims
Here we examine ways in which the impacts of external (environmental) stimuli and constraints on performance are moderated by the animals (deer) on which they impinge.
Key results
The analysis shows (1) how trade-offs in foraging behaviour, illustrated by the timing of activity under the threat of predation, are modulated by integration of short-term metabolic feedback and animal emotions that influence the motivation to feed, (2) how the influence of thermal and nutritional challenges on performance, illustrated by the effect of weather conditions during gestation on the body mass of reindeer (Rangifer tarandus) calves at weaning, depends on the metabolic state of the female at the time the challenge occurs and (3) how annual cycles of growth, appetite and reproduction in seasonal species of deer are governed by innate circannual timers, such that their responses to seasonal changes in food supply are anticipatory and governed by rheostatic systems that adjust homeostatic set- points, rather than being purely reactive.
Conclusions
Concepts like ‘maintenance’ and ‘energy balance’, which were originally derived from non-seasonal domestic ruminants, are unable to account for annual cycles in metabolic and nutritional status in seasonal deer. Contrasting seasonal phenotypes (fat and anoestrous in summer, lean and oestrous in winter) represent adaptive solutions to the predictable challenges presented by contrasting seasonal environments, not failure of homeostasis in one season and its success in another.
Implications
The analysis and interpretation of responses to environment in terms of interaction between the external stimuli and the internal systems that govern them offer a more comprehensive, multifaceted understanding of the influence of environmental variation on performance in deer and open lines of ecological enquiry defined by non-intuitive aspects of animal function.
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Characterisation of the effect of day length, and associated differences in dietary intake, on the gut microbiota of Soay sheep. Arch Microbiol 2019; 201:889-896. [PMID: 30968220 PMCID: PMC6687699 DOI: 10.1007/s00203-019-01652-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 03/08/2019] [Accepted: 03/13/2019] [Indexed: 11/24/2022]
Abstract
Differences in the rumen bacterial community have been previously reported for Soay sheep housed under different day length conditions. This study extends this previous investigation to other organs of the digestive tract, as well as the analysis of ciliated protozoa and anaerobic fungi. The detectable concentrations of ciliated protozoa and anaerobic fungi decreased with increased day length in both the rumen and large colon, unlike those of bacteria where no effect was observed. Conversely, bacterial community composition was affected by day length in both the rumen and large colon, but the community composition of the detectable ciliated protozoa and anaerobic fungi was not affected. Day length-associated differences in the bacterial community composition extended to all of the organs examined, with the exception of the duodenum and the jejunum. It is proposed that differences in rumen fill and ruminal ‘by-pass’ nutrients together with endocrinological changes cause the observed effects of day length on the different gut microbial communities.
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Cipolla-Neto J, Amaral FGD. Melatonin as a Hormone: New Physiological and Clinical Insights. Endocr Rev 2018; 39:990-1028. [PMID: 30215696 DOI: 10.1210/er.2018-00084] [Citation(s) in RCA: 305] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 06/21/2018] [Indexed: 02/07/2023]
Abstract
Melatonin is a ubiquitous molecule present in almost every live being from bacteria to humans. In vertebrates, besides being produced in peripheral tissues and acting as an autocrine and paracrine signal, melatonin is centrally synthetized by a neuroendocrine organ, the pineal gland. Independently of the considered species, pineal hormone melatonin is always produced during the night and its production and secretory episode duration are directly dependent on the length of the night. As its production is tightly linked to the light/dark cycle, melatonin main hormonal systemic integrative action is to coordinate behavioral and physiological adaptations to the environmental geophysical day and season. The circadian signal is dependent on its daily production regularity, on the contrast between day and night concentrations, and on specially developed ways of action. During its daily secretory episode, melatonin coordinates the night adaptive physiology through immediate effects and primes the day adaptive responses through prospective effects that will only appear at daytime, when melatonin is absent. Similarly, the annual history of the daily melatonin secretory episode duration primes the central nervous/endocrine system to the seasons to come. Remarkably, maternal melatonin programs the fetuses' behavior and physiology to cope with the environmental light/dark cycle and season after birth. These unique ways of action turn melatonin into a biological time-domain-acting molecule. The present review focuses on the above considerations, proposes a putative classification of clinical melatonin dysfunctions, and discusses general guidelines to the therapeutic use of melatonin.
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Affiliation(s)
- José Cipolla-Neto
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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10
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Ungerfeld R, Freitas-de-Melo A, Giriboni J, Lacuesta L, Toledano-Díaz A, Santiago-Moreno J. Influence of seasonality and stimulus of oestrous does in bucks' aggressiveness. Behav Processes 2016; 133:1-5. [PMID: 27744086 DOI: 10.1016/j.beproc.2016.10.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 09/02/2016] [Accepted: 10/11/2016] [Indexed: 11/26/2022]
Abstract
Aggressiveness is directly related to testosterone concentration, which varies with seasons and in response to female stimulation. The aim was to determine if the frequency and pattern of agonistic interactions between bucks varies seasonally and in response to oestrous female stimulation. In the first study we characterized the pattern of agonistic interactions during feeding throughout a whole year in groups of Iberian ibex bucks; and in the second study, we determined the influence of oestrous does on the frequencies of agonistic behaviours between Gabon bucks in different seasons. In Iberian ibex bucks, the frequency of agonistic behaviours was maximum in summer and testosterone concentration in late autumn. In Gabon bucks, total agonistic interactions increased in bucks stimulated by females in late summer and autumn. In late autumn there were more interactions without physical contact in stimulated than in isolated bucks. Aggressiveness in bucks varied along the year, but the seasonal pattern was related to the context in which behaviours were recorded. Stimulation with oestrous females induced an increase of aggressiveness during the breeding season. At least in the conditions of these studies, testosterone concentrations seemed not to be the main influence on the frequency in which aggressive behaviour was displayed.
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Affiliation(s)
- Rodolfo Ungerfeld
- Departamento de Fisiología, Facultad de Veterinaria, Universidad de la República, Lasplaces 1620, 11600, Montevideo, Uruguay.
| | - Aline Freitas-de-Melo
- Departamento de Biología Molecular y Celular, Facultad de Veterinaria, Universidad de la República, Lasplaces 1620, 11600, Montevideo, Uruguay
| | - Julia Giriboni
- Departamento de Fisiología, Facultad de Veterinaria, Universidad de la República, Lasplaces 1620, 11600, Montevideo, Uruguay
| | - Lorena Lacuesta
- Departamento de Fisiología, Facultad de Veterinaria, Universidad de la República, Lasplaces 1620, 11600, Montevideo, Uruguay
| | - Adolfo Toledano-Díaz
- Departamento de Reproducción Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Av. Puerta de Hierro s/n, 28040 Madrid, Spain
| | - Julián Santiago-Moreno
- Departamento de Reproducción Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Av. Puerta de Hierro s/n, 28040 Madrid, Spain
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11
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Tyler NJC, Gregorini P, Forchhammer MC, Stokkan KA, van Oort BEH, Hazlerigg DG. Behavioral Timing without Clockwork: Photoperiod-Dependent Trade-Off between Predation Hazard and Energy Balance in an Arctic Ungulate. J Biol Rhythms 2016; 31:522-33. [PMID: 27634928 DOI: 10.1177/0748730416662778] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Occurrence of 24-h rhythms in species apparently lacking functional molecular clockwork indicates that strong circadian mechanisms are not essential prerequisites of robust timing, and that rhythmical patterns may arise instead as passive responses to periodically changing environmental stimuli. Thus, in a new synthesis of grazing in a ruminant (MINDY), crepuscular peaks of activity emerge from interactions between internal and external stimuli that influence motivation to feed, and the influence of the light/dark cycle is mediated through the effect of low nocturnal levels of food intake on gastric function. Drawing on risk allocation theory, we hypothesized that the timing of behavior in ruminants is influenced by the independent effects of light on motivation to feed and perceived risk of predation. We predicted that the antithetical relationship between these 2 drivers would vary with photoperiod, resulting in a systematic shift in the phase of activity relative to the solar cycle across the year. This prediction was formalized in a model in which phase of activity emerges from a photoperiod-dependent trade-off between food and safety. We tested this model using data on the temporal pattern of activity in reindeer/caribou Rangifer tarandus free-living at natural mountain pasture in sub-Arctic Norway. The resulting nonlinear relationship between the phasing of crepuscular activity and photoperiod, consistent with the model, suggests a mechanism for behavioral timing that is independent of the core circadian system. We anticipate that such timing depends on integration of metabolic feedback from the digestive system and the activity of the glucocorticoid axis which modulates the behavioral responses of the animal to environmental hazard. The hypothalamus is the obvious neural substrate to achieve this integration.
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Affiliation(s)
- Nicholas J C Tyler
- Centre for Saami Studies, UiT The Arctic University of Norway, Tromsø, Norway
| | | | - Mads C Forchhammer
- The University Centre in Svalbard (UNIS), Longyearbyen, Norway Center for Macroecology, Evolution and Climate (CMEC) and Greenland Perspective, Natural History Museum of Denmark, Copenhagen, Denmark
| | - Karl-Arne Stokkan
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
| | | | - David G Hazlerigg
- Department of Arctic and Marine Biology, UiT The Arctic University of Norway, Tromsø, Norway
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Wang W, He L, Liu B, Li L, Wei N, Zhou R, Qi L, Liu S, Hu D. Feeding performance and preferences of captive forest musk deer while on a cafeteria diet. FOLIA ZOOLOGICA 2015. [DOI: 10.25225/fozo.v64.i2.a8.2015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Wenxia Wang
- Lab of Non-invasive Research Technology for Endangered Species, College of Nature Conservation, Beijing Forestry University, Beijing 100083, China;,
| | - Lan He
- Lab of Non-invasive Research Technology for Endangered Species, College of Nature Conservation, Beijing Forestry University, Beijing 100083, China;,
- College of Life Science, Xinjiang Normal University, Urumqi, Xinjiang 830054, China
| | - Baoqing Liu
- Breeding Centre of Forest Musk Deer in Pien Tze Huang, Baoji 721000, China
| | - Linhai Li
- Beijing Natural History Museum, Beijing 100050, China
| | - Ning Wei
- Lab of Non-invasive Research Technology for Endangered Species, College of Nature Conservation, Beijing Forestry University, Beijing 100083, China;,
| | - Ran Zhou
- Lab of Non-invasive Research Technology for Endangered Species, College of Nature Conservation, Beijing Forestry University, Beijing 100083, China;,
| | - Lei Qi
- Lab of Non-invasive Research Technology for Endangered Species, College of Nature Conservation, Beijing Forestry University, Beijing 100083, China;,
| | - Shuqiang Liu
- Lab of Non-invasive Research Technology for Endangered Species, College of Nature Conservation, Beijing Forestry University, Beijing 100083, China;,
| | - Defu Hu
- Lab of Non-invasive Research Technology for Endangered Species, College of Nature Conservation, Beijing Forestry University, Beijing 100083, China;,
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Nie HT, Wan YJ, You JH, Wang ZY, Lan S, Fan YX, Wang F. Effect of Age on Energy Requirement for Maintenance and Growth of Dorper and Hu Crossbred F1 Ewes Weighing 20 to 50 kg. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2015; 28:1140-9. [PMID: 26104522 PMCID: PMC4478482 DOI: 10.5713/ajas.14.0403] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 08/16/2014] [Accepted: 08/31/2014] [Indexed: 11/27/2022]
Abstract
This research aimed to define the energy requirement of Dorper and Hu Hybrid F1 ewes 20 to 50 kg of body weight, furthermore to study energy requirement changes with age and evaluate the effect of age on energy requirement parameters. In comparative slaughter trial, thirty animals were divided into three dry matter intake treatments (ad libitum, n = 18; low restricted, n = 6; high restricted, n = 6), and were all slaughtered as baseline, intermediate, and final slaughter groups, to calculate body chemical components and energy retained. In digestibility trial, twelve ewes were housed in individual metabolic cages and randomly assigned to three feeding treatments in accordance with the design of a comparative slaughter trial, to evaluate dietary energetic values at different feed intake levels. The combined data indicated that, with increasing age, the net energy requirement for maintenance (NEm) decreased from 260.62±13.21 to 250.61±11.79 kJ/kg0.75 of shrunk body weight (SBW)/d, and metabolizable energy requirement for maintenance (MEm) decreased from 401.99±20.31 to 371.23±17.47 kJ/kg0.75 of SBW/d. Partial efficiency of ME utilization for maintenance (km, 0.65 vs 0.68) and growth (kg, 0.42 vs 0.41) did not differ (p>0.05) due to age; At the similar condition of average daily gain, net energy requirements for growth (NEg) and metabolizable energy requirements for growth (MEg) for ewes during late fattening period were 23% and 25% greater than corresponding values of ewes during early fattening period. In conclusion, the effect of age upon energy requirement parameters in the present study were similar in tendency with previous recommendations, values of energy requirement for growth (NEg and MEg) for Dorper and Hu crossbred female lambs ranged between the NRC (2007) recommendation for early and later maturating growing sheep.
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Affiliation(s)
- H T Nie
- Jiangsu Engineering Technology Research Center of Meat Sheep and Goat Industry, College of Animal Science, Nanjing Agricultural University, Nanjing 210095, China
| | - Y J Wan
- Research center of Haimen Goats, College of Animal Science, Nanjing Agricultural University, Haimen, Jiangsu 226110, China
| | - J H You
- Jiangsu Engineering Technology Research Center of Meat Sheep and Goat Industry, College of Animal Science, Nanjing Agricultural University, Nanjing 210095, China
| | - Z Y Wang
- Jiangsu Engineering Technology Research Center of Meat Sheep and Goat Industry, College of Animal Science, Nanjing Agricultural University, Nanjing 210095, China
| | - S Lan
- Jiangsu Engineering Technology Research Center of Meat Sheep and Goat Industry, College of Animal Science, Nanjing Agricultural University, Nanjing 210095, China
| | - Y X Fan
- Jiangsu Engineering Technology Research Center of Meat Sheep and Goat Industry, College of Animal Science, Nanjing Agricultural University, Nanjing 210095, China
| | - F Wang
- Jiangsu Engineering Technology Research Center of Meat Sheep and Goat Industry, College of Animal Science, Nanjing Agricultural University, Nanjing 210095, China ; Research center of Haimen Goats, College of Animal Science, Nanjing Agricultural University, Haimen, Jiangsu 226110, China
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Salehian Z, Naderi N, Souri M, Mirmahmoudi R, Hozhabri F. Seasonal variation of fibre follicle activity and wool growth in fat-tailed Sanjabi sheep in west Iran. Trop Anim Health Prod 2015; 47:567-73. [PMID: 25616983 DOI: 10.1007/s11250-015-0764-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Accepted: 01/09/2015] [Indexed: 10/24/2022]
Abstract
This experiment was conducted to investigate the seasonal pattern of hair follicle activity, wool growth and fibre diameter (FD) in Sanjabi sheep in west Iran, Kermanshah (34° 18' N and 47° 3' E, elevation 1420 m). Ten male and 10 female Sanjabi sheep with an initial live weight of 32.1 ± 1.3 and 32.7 ± 1.5 (means ± SD), respectively, were used in a 365-day study. A diet was offered with an estimated concentration of 2.18 Mcal metabolizable energy and 130.0 g/kg DM crude protein. Body weight, average daily gain (ADG) and dry matter intake (DMI) were recorded weekly. The percentages of active primary and secondary wool follicles (PAP and PAS), follicle density and the ratio of secondary to primary follicles (S/P) were determined from skin biopsies, taken from the right mid-side of the sheep at monthly intervals. Raw and clean fibre growth rates and FD were measured from left mid-side patches (10 × 10 cm) harvested at the end of every month. There was a gradual increase in live weight throughout the experiment, while ADG and DMI changed in concert with day length. The greatest values for PAP and PAS were observed in summer, whereas lowest were obtained in winter (p < 0.001). Clean wool growth rate and FD were greatest (p < 0.001) in summer and lowest (p < 0.001) in winter. It is concluded that a seasonal cycle of feed intake, body growth, fibre follicle activity, wool growth and FD occur in fat-tailed Sanjabi sheep.
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Affiliation(s)
- Zahra Salehian
- Department of Animal Science, College of Agriculture, Razi University, Kermanshah, Iran
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15
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Influence of nutrition supplementation on the seasonal change in fiber growth and skin follicle activity in both male and female Sanjabi lambs. Small Rumin Res 2015. [DOI: 10.1016/j.smallrumres.2014.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Clarke IJ. Interface between metabolic balance and reproduction in ruminants: focus on the hypothalamus and pituitary. Horm Behav 2014; 66:15-40. [PMID: 24568750 DOI: 10.1016/j.yhbeh.2014.02.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 02/13/2014] [Accepted: 02/15/2014] [Indexed: 01/24/2023]
Abstract
This article is part of a Special Issue "Energy Balance". The interface between metabolic regulators and the reproductive system is reviewed with special reference to the sheep. Even though sheep are ruminants with particular metabolic characteristics, there is a broad consensus across species in the way that the reproductive system is influenced by metabolic state. An update on the neuroendocrinology of reproduction indicates the need to account for the way that kisspeptin provides major drive to gonadotropin releasing hormone (GnRH) neurons and also mediates the feedback effects of gonadal steroids. The way that kisspeptin function is influenced by appetite regulating peptides (ARP) is considered. Another newly recognised factor is gonadotropin inhibitory hormone (GnIH), which has a dual function in that it suppresses reproductive function whilst also acting as an orexigen. Our understanding of the regulation of food intake and energy expenditure has expanded exponentially in the last 3 decades and historical perspective is provided. The function of the regulatory factors and the hypothalamic cellular systems involved is reviewed with special reference to the sheep. Less is known of these systems in the cow, especially the dairy cow, in which a major fertility issue has emerged in parallel with selection for increased milk production. Other endocrine systems--the hypothalamo-pituitary-adrenal axis, the growth hormone (GH) axis and the thyroid hormones--are influenced by metabolic state and are relevant to the interface between metabolic function and reproduction. Special consideration is given to issues such as season and lactation, where the relationship between metabolic hormones and reproductive function is altered.
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Affiliation(s)
- Iain J Clarke
- Monash University, Department of Physiology, Wellington Road, Clayton 3168, Australia.
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17
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Thompson D, Barboza P. Nutritional implications of increased shrub cover for caribou (Rangifer tarandus) in the Arctic. CAN J ZOOL 2014. [DOI: 10.1139/cjz-2013-0265] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Shrubs are increasing in the annual range of arctic caribou (Rangifer tarandus (L., 1758)), but it is unknown how much summer browse caribou could consume. We measured instantaneous intakes of resin birch (Betula glandulosa Michx.) and feltleaf willow (Salix alaxensis (Andersson) Coville) by caribou during summer. Daily intake of a formulated diet without toxins was measured during the same period to monitor appetite. Caribou appetite increased from 64.1 to 86.7 g DM·kg–0.75·day−1 as animals gained body mass from 96.8 to 113.5 kg. We estimated that caribou required 645 kJ·kg–0.75·day−1 of digestible energy to maintain body mass and 1113 kJ·kg–0.75·day−1 to gain body mass for autumn reproduction. Caribou had the same bite mass (9.7 mg·bite−1·kg–0.75) and instantaneous intake rate (0.17 g DM·min−1·kg–0.75) on both forages; however, birch contained more phenols (3.3% vs. 1.5%) and less available protein (6.2% vs. 10.2%) than willow. A 100 kg female caribou would need to consume 2.4–8.7 kg of fresh browse, requiring 3.1–8.5 h·day−1 of eating time to meet daily energy requirements. Birch is unlikely to provide enough nitrogen for maintenance of body protein. Therefore, caribou may depend on abundance and diversity of plants to offset toxin loads and low protein intake from shrubs during summer.
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Affiliation(s)
- D.P. Thompson
- Department of Biology and Wildlife, University of Alaska, Fairbanks, P.O. Box 756100, Fairbanks, AK 99775, USA
| | - P.S. Barboza
- Institute of Arctic Biology, Department of Biology and Wildlife, University of Alaska, Fairbanks, P.O. Box 757000, Fairbanks, AK 99775, USA
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Lashley MA, Chitwood MC, Biggerstaff MT, Morina DL, Moorman CE, DePerno CS. White-tailed deer vigilance: the influence of social and environmental factors. PLoS One 2014; 9:e90652. [PMID: 24599090 PMCID: PMC3945222 DOI: 10.1371/journal.pone.0090652] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 02/03/2014] [Indexed: 11/19/2022] Open
Abstract
Vigilance behavior may directly affect fitness of prey animals, and understanding factors influencing vigilance may provide important insight into predator-prey interactions. We used 40,540 pictures taken withcamera traps in August 2011 and 2012to evaluate factors influencing individual vigilance behavior of white-tailed deer (Odocoileus virginianus) while foraging at baited sites. We used binary logistic regression to determine if individual vigilance was affected by age, sex, and group size. Additionally, we evaluated whether the time of the day,moon phase,and presence of other non-predatorwildlife species impacted individual vigilance. Juveniles were 11% less vigilant at baited sites than adults. Females were 46% more vigilant when fawns were present. Males and females spent more time feeding as group size increased, but with each addition of 1 individual to a group, males increased feeding time by nearly double that of females. Individual vigilance fluctuated with time of day andwith moon phase but generally was least during diurnal and moonlit nocturnal hours, indicating deer have the ability to adjust vigilance behavior to changing predation risk associated with varyinglight intensity.White-tailed deer increased individual vigilance when other non-predator wildlife were present. Our data indicate that differential effects of environmental and social constraints on vigilance behavior between sexes may encourage sexual segregation in white-tailed deer.
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Affiliation(s)
- Marcus A Lashley
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, United States of America
- * E-mail:
| | - M. Colter Chitwood
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Michael T. Biggerstaff
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Daniel L. Morina
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Christopher E. Moorman
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Christopher S. DePerno
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, United States of America
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Gregorini P, Beukes PC, Romera AJ, Levy G, Hanigan MD. A model of diurnal grazing patterns and herbage intake of a dairy cow, MINDY: Model description. Ecol Modell 2013. [DOI: 10.1016/j.ecolmodel.2013.09.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Douhard F, Friggens N, Tessier J, Martin O, Tichit M, Sauvant D. Characterization of a changing relationship between milk production and liveweight for dairy goats undergoing extended lactation. J Dairy Sci 2013; 96:5698-711. [DOI: 10.3168/jds.2012-6374] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 06/03/2013] [Indexed: 11/19/2022]
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21
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Monteith KL, Stephenson TR, Bleich VC, Conner MM, Pierce BM, Bowyer RT. Risk-sensitive allocation in seasonal dynamics of fat and protein reserves in a long-lived mammal. J Anim Ecol 2013; 82:377-88. [DOI: 10.1111/1365-2656.12016] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 10/01/2012] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | - Mary M. Conner
- California Department of Fish and Game; Bishop; CA; 93514; USA
| | | | - R. Terry Bowyer
- Department of Biological Sciences; Idaho State University; Pocatello; ID; 83209; USA
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Interactions between nutrition and reproduction in the management of the mature male ruminant. Animal 2012; 4:1214-26. [PMID: 22444618 DOI: 10.1017/s1751731109991674] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In mature male sheep and goats, changes in feed intake seem to have little effect on gonadal endocrine function but induce profound changes on sperm production. These outcomes are due to changes in size of the seminiferous tubules and in spermatogenic efficiency. Except with severe underfeeding, there are only minor changes in the endocrine function of the testis (testosterone production) unless season-long treatments are imposed. For cattle, nutrition clearly affects testicular development and the production of spermatozoa in young bulls, as it does in other species but, after the period of rapid growth has ended, there appears to be little or no response to nutrition. We are developing a clear picture of the metabolic signals, neuroendocrine processes and hormonal control systems that are involved, particularly for the mature male sheep. The energetic components of the diet, rather than protein, seem to be responsible, so we have envisaged a model of the relationship between energy balance and reproduction that has 4 'dimensions': genotype, structure (organs), communication (chemical and neural signals, nutrient sensing) and time (dynamics, metabolic memory, programming). We have linked these perspectives to 'resource allocation theory' and incorporated them into strategies for 'clean, green and ethical animal production'. In contrast to the clear outcomes with respect to spermatogenesis, the effects of nutrition on sexual behaviour are more difficult to define, perhaps because the behaviour is affected by a complex mix of physiological factors and because of flawed methods for quantifying male behaviour. For example, sexual behaviour is compromised by severe feed restriction, but male sexual behaviour requires intensive motor activity so a decline in libido could be caused by general weakness rather than specific nutritional limitations. The interaction between sexual activity and feeding behaviour also complicates the issue under field conditions. At the other end of the scale, overweight males can show reduced sexual success because they have difficulty courting and mounting. For this reason, exercise can enhance the fertilising capacity of rams. This will be important in extensive mating systems where males need to assemble and guard a harem and then mate many times for several weeks. For artificial insemination centres, there seems to be very few data on the nutritional management of males, but problems with overfed animals appear to be a risk. Future research should concentrate on the intra-testicular systems mediating the effects of nutrition on the production of spermatozoa.
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Zerbe P, Clauss M, Codron D, Bingaman Lackey L, Rensch E, Streich JW, Hatt JM, Müller DWH. Reproductive seasonality in captive wild ruminants: implications for biogeographical adaptation, photoperiodic control, and life history. Biol Rev Camb Philos Soc 2012; 87:965-90. [DOI: 10.1111/j.1469-185x.2012.00238.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Turbill C, Ruf T, Mang T, Arnold W. Regulation of heart rate and rumen temperature in red deer: effects of season and food intake. ACTA ACUST UNITED AC 2011; 214:963-70. [PMID: 21346124 DOI: 10.1242/jeb.052282] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Red deer, Cervus elaphus, like other temperate-zone animals, show a large seasonal fluctuation in energy intake and expenditure. Many seasonal phenotypic adjustments are coordinated by endogenous signals entrained to the photoperiod. The cues determining variation in the resting metabolism of ungulates remain equivocal, however, largely because of the confounding effects of food intake and thus the heat increment of feeding. To distinguish endogenous seasonal and environmental effects on metabolism, we subjected 15 female red deer to two feeding treatments, 80% food restriction and low/high protein content, over two winter seasons in a cross-over design experiment. We used rumen-located transmitters to measure heart rate and rumen temperature, which provided indices of metabolism and core body temperature, respectively. Our mixed model (R²=0.85) indicated a residual seasonal effect on mean daily heart rate that was unexplained by the pellet food treatments, activity, body mass or air temperature. In addition to an apparently endogenous down-regulation of heart rate in winter, the deer further reduced heart rate over about 8 days in response to food restriction. We found a strong correlation between rumen temperature and seasonal or periodic variation in heart rate. An effect of lowered rumen (and hence core body) temperature was enhanced during winter, perhaps owing to peripheral cooling, which is known to accompany bouts of hypometabolism. Our experimental results therefore support the hypothesis that a reduction in body temperature is a physiological mechanism employed even by large mammals, like red deer, to reduce their energy expenditure during periods of negative energy balance.
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Affiliation(s)
- Christopher Turbill
- Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Savoyenstrasse 1, Vienna, Austria
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25
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Dugdale AHA, Curtis GC, Harris PA, Argo CM. Assessment of body fat in the pony: part I. Relationships between the anatomical distribution of adipose tissue, body composition and body condition. Equine Vet J 2011; 43:552-61. [PMID: 21496091 DOI: 10.1111/j.2042-3306.2010.00330.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
REASONS FOR PERFORMING STUDY Evaluation of equine body fat content is important for nutritional and clinical purposes. However, our understanding of total body fat and its regional distribution in the body is sparse. Currently, body fat evaluation relies on the subjective assessment of body condition score (BCS), which has never been validated against 'gold standard' chemical analysis or dissection measurements in ponies. OBJECTIVES To define the relationships between subjective (BCS), objective (morphometric) indices of body fat and 'gold standard' measurements of actual body composition. HYPOTHESES BCS and morphometry offer valid, noninvasive methods for determination of body fat in equids. METHODS Seven mature (mean ± s.e. 13 ± 3 years, 212 ± 14 kg, BCS 1.25-7/9), Welsh Mountain pony mares, destined for euthanasia (for nonresearch purposes), were used. For all ponies, body mass (BM), BCS and various morphometric measurements were recorded. Following euthanasia, all ponies were systematically dissected. Discrete white adipose tissue (WAT) depots were independently described. Gross, body chemical composition was determined by proximate analyses. RESULTS Total somatic soft tissues increased linearly (r(2) = 1.00), whereas body WAT content (1-26% live BM) increased exponentially (r(2) = 0.96), with BCS. WAT was equally distributed between internal and external sites in all animals irrespective of BCS. Nuchal fat was a poor predictor of total WAT (r(2) = 0.66). Periorbital WAT did not alter with BCS (r(2) = 0.01). Heart girth:withers height and ultrasonic retroperitoneal fat depth were closely associated with total, chemically-extracted lipid which comprised 1-29% live BM (r(2) = 0.91 and 0.88, respectively). CONCLUSIONS AND POTENTIAL RELEVANCE The exponential relationship between BCS and total body WAT/lipid suggests that BCS is unlikely to be a sensitive index of body fat for animals in moderate-obese states. Morphometric measurements (body girths and retroperitonel fat depth) may be useful to augment subjective BCS systems.
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Affiliation(s)
- A H A Dugdale
- University of Liverpool, School of Veterinary Science, Leahurst, Neston, UK
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26
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Dugdale AHA, Curtis GC, Cripps PJ, Harris PA, Argo CM. Effects of season and body condition on appetite, body mass and body composition in ad libitum fed pony mares. Vet J 2010; 190:329-37. [PMID: 21146430 DOI: 10.1016/j.tvjl.2010.11.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 11/09/2010] [Accepted: 11/10/2010] [Indexed: 11/29/2022]
Abstract
Changes in appetite, body mass (BM), body condition score (BCS), direct (ultrasonographic) and indirect (deuterium oxide dilution technique) measures of body fat were monitored in Welsh Mountain pony mares (n=11, 5-19 years of age) offered ad libitum access to a complete diet (gross energy 16.9±0.07 MJ/kg dry matter) for 12 weeks during summer (n=6; 246±20 kg) and winter (n=5; 219±21 kg). At the outset, each group comprised two thin (BCS 1-3/9), moderate (BCS 4-6/9) and obese (BCS 7-9/9) animals. For ponies that were non-obese at the outset, BM was gained more rapidly (P=0.001) in summer (0.8±0.1 kg/day) than winter (0.6±0.0 kg/day). This was associated with a seasonal increase in dry matter intake (DMI) which became maximal (summer, 4.6±0.3% BM as DMI/day; winter, 3.5±0.1% BM as DMI/day) during the second month. The appetite of the obese ponies was half that reported for non-obese animals in the summer and BM remained constant irrespective of season. Body 'fatness' increased progressively for non-obese but not obese ponies. Body fat content was exponentially associated with increasing BCS but BCSs >6 were not useful indicators of actual body fat. Endogenous circannual mechanisms to suppress winter weight gain were insufficient to prevent the development of obesity in ad libitum fed ponies.
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Affiliation(s)
- Alexandra H A Dugdale
- University of Liverpool, School of Veterinary Science, Leahurst, Chester High Road, Neston, Wirral CH64 7TE, UK
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Evolutionary adaptations of ruminants and their potential relevance for modern production systems. Animal 2010; 4:979-92. [DOI: 10.1017/s1751731110000388] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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28
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Couturier S, Côté SD, Huot J, Otto RD. Body-condition dynamics in a northern ungulate gaining fat in winter. CAN J ZOOL 2009. [DOI: 10.1139/z09-020] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Individual condition generally depends on density and is partly determined by habitat quality and climate. We studied long-term trends in the condition and productivity of female caribou ( Rangifer tarandus (L., 1758)) in two large migratory herds in the Quebec–Labrador peninsula (Canada), the George and the Feuilles herds. Females from the George herd were in better summer condition than those from the more abundant Feuilles herd in 2001–2002, while it was the opposite in 1988 when the Feuilles herd was less abundant than the George herd. Summer nutrition followed the same pattern between herds through time. Spring body condition of females in the George herd declined from 1976 to the mid-1980s during early population growth. Fall condition, however, did not change from 1983 to 2002 when caribou numbers first peaked and later declined. Pregnancy rates were inversely related to herd size in both herds. Vegetation quality (NDVI) in June was significantly related to body proteins in the fall. Albeit unusual for a northern ungulate, body fat increased from fall to spring in the George herd. We conclude that a relatively small and highly grazed summer range, as well as density-dependent effects, affected summer nutrition and the need to continue lipogenesis during winter.
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Affiliation(s)
- Serge Couturier
- Ministère des Ressources naturelles et de la Faune, Direction de la recherche sur la faune, 880 chemin Ste-Foy, Québec, QC G1S 4X4, Canada
- Département de biologie and Centre d’études nordiques, Université Laval, 1045 avenue de la Médecine, Québec, QC G1V 0A6, Canada
- Wildlife Division, Department of Environment and Conservation, P.O. Box 2007, Corner Brook, NL A2H 7S1, Canada
| | - Steeve D. Côté
- Ministère des Ressources naturelles et de la Faune, Direction de la recherche sur la faune, 880 chemin Ste-Foy, Québec, QC G1S 4X4, Canada
- Département de biologie and Centre d’études nordiques, Université Laval, 1045 avenue de la Médecine, Québec, QC G1V 0A6, Canada
- Wildlife Division, Department of Environment and Conservation, P.O. Box 2007, Corner Brook, NL A2H 7S1, Canada
| | - Jean Huot
- Ministère des Ressources naturelles et de la Faune, Direction de la recherche sur la faune, 880 chemin Ste-Foy, Québec, QC G1S 4X4, Canada
- Département de biologie and Centre d’études nordiques, Université Laval, 1045 avenue de la Médecine, Québec, QC G1V 0A6, Canada
- Wildlife Division, Department of Environment and Conservation, P.O. Box 2007, Corner Brook, NL A2H 7S1, Canada
| | - Robert D. Otto
- Ministère des Ressources naturelles et de la Faune, Direction de la recherche sur la faune, 880 chemin Ste-Foy, Québec, QC G1S 4X4, Canada
- Département de biologie and Centre d’études nordiques, Université Laval, 1045 avenue de la Médecine, Québec, QC G1V 0A6, Canada
- Wildlife Division, Department of Environment and Conservation, P.O. Box 2007, Corner Brook, NL A2H 7S1, Canada
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Neuroendocrine and physiological regulation of intake with particular reference to domesticated ruminant animals. Nutr Res Rev 2009; 21:207-34. [PMID: 19087372 DOI: 10.1017/s0954422408138744] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The central nervous system undertakes the homeostatic role of sensing nutrient intake and body reserves, integrating the information, and regulating energy intake and/or energy expenditure. Few tasks regulated by the brain hold greater survival value, particularly important in farmed ruminant species, where the demands of pregnancy, lactation and/or growth are not easily met by often bulky plant-based and sometimes nutrient-sparse diets. Information regarding metabolic state can be transmitted to the appetite control centres of the brain by a diverse array of signals, such as stimulation of the vagus nerve, or metabolic 'feedback' factors derived from the pituitary gland, adipose tissue, stomach/abomasum, intestine, pancreas and/or muscle. These signals act directly on the neurons located in the arcuate nucleus of the medio-basal hypothalamus, a key integration, and hunger (orexigenic) and satiety (anorexigenic) control centre of the brain. Interest in human obesity and associated disorders has fuelled considerable research effort in this area, resulting in increased understanding of chronic and acute factors influencing feed intake. In recent years, research has demonstrated that these results have relevance to animal production, with genetic selection for production found to affect orexigenic hormones, feeding found to reduce the concentration of acute controllers of orexigenic signals, and exogenous administration of orexigenic hormones (i.e. growth hormone or ghrelin) reportedly increasing DM intake in ruminant animals as well as single-stomached species. The current state of knowledge on factors influencing the hypothalamic orexigenic and anorexigenic control centres is reviewed, particularly as it relates to domesticated ruminant animals, and potential avenues for future research are identified.
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Barboza P, Parker K. Allocating Protein to Reproduction in Arctic Reindeer and Caribou. Physiol Biochem Zool 2008; 81:835-55. [DOI: 10.1086/590414] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Shi PJ, Meng K, Zhou ZG, Wang YR, Diao QY, Yao B. The host species affects the microbial community in the goat rumen. Lett Appl Microbiol 2007; 46:132-5. [PMID: 17971095 DOI: 10.1111/j.1472-765x.2007.02274.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS This study was carried out to determine whether bacterial and ciliate populations in goat rumen vary significantly between different goat species living in the same environment. METHODS AND RESULTS Bacterial and ciliate communities in the rumen of three goat species were analysed at the molecular level using denaturing gradient gel electrophoresis. The microbial community varied considerably among goats living in the same environment. Interspecies variation in the bacterial population was noticeably greater than intraspecies variation. In contrast, there was considerable variation in the ciliate population among goats within the same species, and intraspecies similarities were no greater than those observed across species. CONCLUSIONS Because environmental factors and diets were identical for all goats, differences in bacterial populations reflect species-specific differences in rumen microbes. SIGNIFICANCE AND IMPACT OF THE STUDY Factors related to the host species have an important effect on determining the bacterial composition in the goat rumen.
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Affiliation(s)
- P J Shi
- Microbial Engineering Department, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
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32
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The physiological and metabolic impacts on sheep and cattle of feed and water deprivation before and during transport. Nutr Res Rev 2007; 20:17-28. [DOI: 10.1017/s0954422407745006] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Sheep and cattle are frequently subjected to feed and water deprivation (FWD) for about 12 h before, and then during, transport to reduce digesta load in the gastrointestinal tract. This FWD is marked by weight loss as urine and faeces mainly in the first 24 h but continuing at a reduced rate subsequently. The weight of rumen contents falls although water loss is to some extent masked by saliva inflow. FWD is associated with some stress, particularly when transportation is added. This is indicated by increased levels of plasma cortisol that may be partly responsible for an observed increase in the output of water and N in urine and faeces. Loss of body water induces dehydration that may induce feelings of thirst by effects on the hypothalamus structures through the renin–angiotensin–aldosterone system. There are suggestions that elevated cortisol levels depress angiotensin activity and prevent sensations of thirst in dehydrated animals, but further research in this area is needed. Dehydration coupled with the discharge of Na in urine challenges the maintenance of homeostasis. In FWD, Na excretion in urine is reduced and, with the reduction in digesta load, Na is gradually returned from the digestive tract to the extracellular fluid space. Control of enteropathogenic bacteria by normal rumen microbes is weakened by FWD and resulting infections may threaten animal health and meat safety. Recovery time is required after transport to restore full feed intake and to ensure that adequate glycogen is present in muscle pre-slaughter to maintain meat quality.
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Pearson RA, Archibald RF, Muirhead RH. A comparison of the effect of forage type and level of feeding on the digestibility and gastrointestinal mean retention time of dry forages given to cattle, sheep, ponies and donkeys. Br J Nutr 2007; 95:88-98. [PMID: 16441920 DOI: 10.1079/bjn20051617] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Four cattle, sheep, ponies and donkeys were fed dehydrated lucerne, early-cut hay, later-cut hay or barley straw in a Latin square-based design for four periods of 35d. In the first sub-period animals were fed the dietsad libitum(1–21d) and in the second sub-period they were fed the same diet restricted to 0·75 ofad libitumintake (days 22–35). Measurements of forage intake, apparent digestibilities and gastrointestinal mean retention times (MRT) were made in the last 7d of each sub-period. Differences between species in voluntary DM intake (VDMI; g/kg live weight LW)0·75and g/LW) were greatest on the lucerne and least on barley straw. Cattle VDMI (g/kg LW0·75) compared with intake of the other species was > ponies > sheep > donkeys on lucerne. On barley straw VDMI (g/kg LW0·75) of cattle compared with intake of the other species was = donkey = ponies > sheep. VDMI of hays were intermediate between the lucerne and straw forages. Apparent digestibilities of DM, organic matter (OM), neutral-detergent fibre (NDF) and acid-detergent fibre (ADF) of the lucerne and hays were higher in the ruminants than in the equids. Effect of feeding level was not significant. Gastrointestinal MRT was shorter in the equids than in the ruminants. On straw diets donkeys showed similar apparent digestibilities of feed components to those of the cattle, whilst apparent digestibility of the straw diet by the ponies was lowest. Results are discussed in relation to evolutionary differences in feeding and digestion strategy associated with fore- or hind-gut fermentation in ruminants and equids.
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Affiliation(s)
- R A Pearson
- Centre for Tropical Veterinary Medicine, University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian EH25 9RG, UK.
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Gootwine E, Rozov A. Seasonal effects on birth weight of lambs born to prolific ewes maintained under intensive management. Livest Sci 2006. [DOI: 10.1016/j.livsci.2006.06.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Crater AR, Barboza PS, Forster RJ. Regulation of rumen fermentation during seasonal fluctuations in food intake of muskoxen. Comp Biochem Physiol A Mol Integr Physiol 2006; 146:233-41. [PMID: 17134925 DOI: 10.1016/j.cbpa.2006.10.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2006] [Revised: 10/07/2006] [Accepted: 10/15/2006] [Indexed: 11/20/2022]
Abstract
We studied rumen fermentation of castrated adult muskoxen (Ovibos moschatus; n=4) during periods of low (May) and high (August) food intake. Turnover time (17+/-1.8 h) and volume (26+/-3.9 L) of rumen fluid were consistent between May and August and among days within each season. Rumen temperature did not vary significantly during the day (38.8+/-0.29 degrees C) in either season. Rumen osmolality (271.9+/-16.4 vs. 245.9+/-11.4 mOsm kg(-1)) and pH (6.81+/-0.31 vs. 6.39+/-0.15) were higher in May than in August indicating a shift in the allostatic set point. Rumen fluid pH was more variable in May than in August both before and after a single meal of fermentable substrate even though fermentation acids were lower in May than in August (101.0+/-11.0 vs. 126.0+/-8.74 mM). Changing proportions of minor fermentation acids indicated a shift in metabolic pathways even though bacterial numbers were similar between seasons (6.4+/-5.8x10(9) mL(-1)). Allostatic set points probably alter the homeostatic range of conditions and the microbial diversity of fermentations in herbivores from highly seasonal environments.
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Affiliation(s)
- Annie R Crater
- Department of Biology and Wildlife, PO Box 6100, University of Alaska, Fairbanks, Alaska 99775-6100, USA
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Barboza PS, Parker KL. Body Protein Stores and Isotopic Indicators of N Balance in Female Reindeer (Rangifer tarandus) during Winter. Physiol Biochem Zool 2006; 79:628-44. [PMID: 16691528 DOI: 10.1086/502811] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2005] [Indexed: 11/03/2022]
Abstract
We studied bred and unbred female reindeer (Rangifer tarandus tarandus) during 12 wk of winter when ambient temperatures were low and nitrogen (N) demand for fetal growth is highest in pregnant females. Animals were fed a complete pelleted diet ad lib. that contained 2.54% N in dry matter that was 80% +/- 2% (X +/- SD) digestible. Female reindeer lost 64% +/- 14% of body fat but gained 34% +/- 11% of lean mass from 10 wk prepartum to parturition. These changes were equivalent to average balances of -14.14 +/- 2.35 MJ d(-1) and 10 +/- 3 g N d(-1). Blood cells, serum, and urine declined in (15)N/(14)N in late winter as body protein was gained from the diet. Blood cells of newborn calves were more enriched in (15)N and (13)C than that of their mothers, indicating the deposition of fetal protein from maternal stores. To quantify pathways of N flow in reindeer, N balance was measured by confining animals to cages for 10 d at 4 wk from parturition. N balance was inversely related to (15)N/(14)N in urea-N but not related to (15)N/(14)N of blood cells, creatinine, and feces. The proportion of urea-N derived from body protein increased above 0.46 as N balance fell below -200 mg N kg(-0.75) d(-1). Proportions of urea-N from body protein were -0.01 +/- 0.21 in pregnant females before and after caging and were consistent with average body protein gain in winter. Storage of protein allows reindeer and caribou to tolerate diets that are low in N without impairing fetal development.
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Affiliation(s)
- Perry S Barboza
- Institute of Arctic Biology, Department of Biology and Wildlife, University of Alaska, Fairbanks, 99775-7000, USA.
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Barboza PS, Hume ID. Physiology of intermittent feeding: integrating responses of vertebrates to nutritional deficit and excess. Physiol Biochem Zool 2006; 79:250-64. [PMID: 16555185 DOI: 10.1086/499984] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/25/2005] [Indexed: 11/03/2022]
Abstract
Food intakes of wild animals may not match their requirements for nutrients and energy but may vary between periods of nutritional excess (hyperphagia) and nutritional deficit (hypophagia) at timescales that vary from days to months. We present a simple model of feeding patterns and requirements of vertebrates. Frequent fasts and high intakes are typical of endothermic predators and migratory birds, whereas slow cycles and long deficits typify feeding patterns of ectothermic predators and ungulates in seasonal environments. We propose that hyperphagia is constrained by the ability to increase processes of digestion, absorption, intermediary metabolism, net deposition in tissue, and excretion to match loads of digesta and metabolites. Hyperphagia on high-quality diets is limited by the clearance of metabolites, whereas digestive tract capacity and flow limit consumption of low-quality diets. Of all digestive strategies, small omnivores with simple digestive systems may be the most tolerant of frequent hyperphagia. Tolerance of hypophagia favors large endogenous stores or low mass-specific rates of metabolism and reproductive output. Large animals may be most able to sustain reproduction during prolonged deficits in seasonal environments. Responses to excessive and deficient intakes of food are constrained by the length of the feeding cycle. Animals adapted to short feeding cycles may be best suited to unpredictable food supplies but at the energetic cost of maintaining spare capacity for digestion and absorption. Predictions of the response to food disruption are best evaluated in the context of body size, nutritional physiology, and life history of the species and the time for internal response.
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Affiliation(s)
- Perry S Barboza
- Department of Biology and Wildlife, Institute of Arctic Biology, P.O. Box 757000, University of Alaska, Fairbanks, AK 99775-7000, USA.
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McEwan NR, Abecia L, Regensbogenova M, Adam CL, Findlay PA, Newbold CJ. Rumen microbial population dynamics in response to photoperiod. Lett Appl Microbiol 2005; 41:97-101. [PMID: 15960760 DOI: 10.1111/j.1472-765x.2005.01707.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS This work was carried out to determine if there was a difference in the microbial population of the rumen associated with daylength at which sheep are housed. METHODS AND RESULTS Denaturing gradient gel electrophoresis (DGGE) was used to study the ciliate and bacterial diversity in the rumen of Soay rams kept in long day (16 h light) or short day (8 h light) photoperiods. Bacterial diversity varied according to the daylength conditions where the host animal was housed, as did total volatile fatty acids (VFA) concentrations. No differences associated with daylength were detected in ciliate diversity, branched VFA concentrations or the ruminal ammonia concentrations. CONCLUSIONS As diets had identical composition, yet voluntary intakes levels were higher during long days, it is proposed that the differences in bacterial populations arise because of the differences in amount of food consumed. SIGNIFICANCE AND IMPACT OF THE STUDY The outcome of this study demonstrated that factors beyond dietary composition must be taken into account when trying to study microbial populations, even in what can be considered a fairly constant environment.
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Affiliation(s)
- N R McEwan
- Gut Microbiology and Immunology Division, Rowett Research Institute, Aberdeen, UK.
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Alila-Johansson A, Eriksson L, Soveri T, Laakso ML. Daily and annual variations of free fatty acid, glycerol and leptin plasma concentrations in goats (Capra hircus) under different photoperiods. Comp Biochem Physiol A Mol Integr Physiol 2004; 138:119-31. [PMID: 15275646 DOI: 10.1016/j.cbpb.2004.02.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2003] [Revised: 02/15/2004] [Accepted: 02/16/2004] [Indexed: 11/22/2022]
Abstract
The aim of the study was to differentiate the impact of lighting conditions and feeding times on the regulation of lipid metabolism of goats under different photoperiods throughout the year. Seven Finnish landrace goats were kept under artificial lighting that simulated the annual changes of photoperiod at 60 degrees N (the longest light period 18 h, the shortest 6 h). Ambient temperature and feeding regime were kept constant. Blood samples were collected six times a year at 2-h intervals for 2 days, first in light/dark (LD) conditions and then after 3 days in constant darkness (DD). Significant daily variations were detected in the concentrations of plasma free fatty acids (FFA) and glycerol throughout the year. The nocturnal decrease and morning rise of FFA levels were related to the photoperiod, while the trough levels of glycerol were associated with the concentrate meal times. In DD conditions, FFA and glycerol rhythms were unstable. A significant seasonal variation was detected in the overall FFA and glycerol levels suggesting decreased lipogenesis in winter, increased lipolysis in spring and high lipogenesis in summer and fall. There was no significant daily rhythm in serum leptin levels, nor did the profiles in LD and DD conditions differ. The leptin level was slightly lower in early fall than in the other seasons, paralleling a small decrease of body mass in the goats after the grazing season. The daily or annual variations of FFA and glycerol levels were not clearly related to leptin concentrations. The results suggest that lipid metabolism of goats is regulated by light even in constant temperature and feeding conditions; however, no significant contribution of leptin levels could be shown.
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Affiliation(s)
- Aino Alila-Johansson
- Faculty of Veterinary Medicine, Department of Basic Veterinary Sciences, POB 57, FIN-00014 University of Helsinki, Helsinki, Finland.
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Lawler JP, White RG. Temporal responses in energy expenditure and respiratory quotient following feeding in the muskox: influence of season on energy costs of eating and standing and an endogenous heat increment. CAN J ZOOL 2003. [DOI: 10.1139/z03-133] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Seasonal energy metabolism was investigated in young (2- to 3-year-old) muskoxen (Ovibos moschatus) during the winters of 1994 (JanuaryApril) and 1996 (January) and summer of 1995 (July and August). Energy expenditure (EE) increased 35%42% following a meal of chopped brome hay (Bromus inermis) and declined as a double-exponential process over 8 h. The mean energy cost of eating (321 and 361 J·g dry matter1) was lower in winter than in summer, and declined with body mass (BM) (r2 = 0.58). The mean energy cost of standing was 21% (SE = 2.7%) higher than that of bedding. Prefeeding energy expenditure (EEp) was 26% higher in summer than in winter. An endo genous heat increment, measured as EEp EE, at 7-8 h post feeding was lower (P < 0.001) in winter than in summer (39 and 58 kJ·kg BM0.75·d1, respectively). Mean cumulative EE (minus activity costs) for 8 h post feeding was 124 (SE = 4) and 148 (SE = 4) kJ·kg BM0.75 (P < 0.001) in winter and summer, respectively. Respiratory quotients (RQs) >1 were recorded during feeding in winter and a mean RQ of 0.9 was recorded in summer. Seasonal EEp, postfeeding EE, and RQ are consistent with a low cost of maintenance metabolism in winter and an increased requirement for productivity in summer.
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Peltier TC, Barboza PS, Blake JE. Seasonal hyperphagia does not reduce digestive efficiency in an Arctic grazer. Physiol Biochem Zool 2003; 76:471-83. [PMID: 13130427 DOI: 10.1086/377744] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2003] [Indexed: 11/03/2022]
Abstract
Muskoxen (Ovibos moschatus) consume fibrous plants that grow rapidly over the short Arctic summer. We studied responses of eight castrated male muskoxen to a diet of grass hay and mineral supplements during spring, autumn, and winter. Animals gained body mass in spring (239+/-39 kg) as body fat content increased from 26% to 38% of ingesta-free mass in winter without changes in lean mass and protein. Intakes of dry matter (DM) increased by 74% between spring and autumn as digestible energy increased from 554 to 923 kJ kg(-0.75) d(-1) during mass gain. Digestibility of cellulose (72%-76%) was not affected by increasing food intake between spring and autumn but was reduced to 65% in winter. Digestibility of nitrogen compounds was 61%-66%, even though intake increased by 134% between spring and autumn. Excess dietary nitrogen from hay and supplements increased urea concentrations in plasma and urine. High loads of solutes such as potassium did not affect plasma or urinary osmolality but were associated with increased rates of glomerular filtration and urinary excretion. Low intakes of sodium from grasses may limit intake and digestion during summer, but high food intakes can support deposition of nitrogen, calcium, magnesium, copper, and zinc in body tissue even when dietary concentrations are low. Seasonal increases in digestive and metabolic functions allow muskoxen to rapidly accumulate energy and nutrients in body tissue during the short season of plant growth.
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Affiliation(s)
- T C Peltier
- Department of Biology and Wildlife, Institute of Arctic Biology, P.O. Box 757000, University of Alaska, Fairbanks, AK 99775-7000, USA
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Rhind SM, Rae MT, Brooks AN. Environmental influences on the fetus and neonate--timing, mechanisms of action and effects on subsequent adult function. Domest Anim Endocrinol 2003; 25:3-11. [PMID: 12963095 DOI: 10.1016/s0739-7240(03)00041-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Environmental influences on fetal and neonatal development can affect neural, reproductive, immune and cardiovascular function in adult humans and animals. The effects can be exerted at many different stages of development from before conception to after birth. Effects may even be exerted during a preceding generation. Some known and some possible mechanisms are reviewed. Systems likely to be affected include the brain, hypothalamus, pituitary and adrenal glands and the gonads. The effects may be exerted through altered gene expression at any stage of development or through changes in organ structure or physiology.
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Affiliation(s)
- S M Rhind
- Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH, UK.
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