1
|
Bus JD, Boumans IJMM, Te Beest DE, Webb LE, Bokkers EAM. Exploring individual responses to welfare issues in growing-finishing pig feeding behaviour. Animal 2024; 18:101192. [PMID: 38843668 DOI: 10.1016/j.animal.2024.101192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 05/06/2024] [Accepted: 05/07/2024] [Indexed: 06/22/2024] Open
Abstract
The feeding behaviour of individual growing-finishing pigs can be continuously monitored using sensors such as electronic feeding stations (EFSs), and this could be further used to monitor pig welfare. To make accurate conclusions about individual pig welfare, however, it is important to know whether deviations in feeding behaviour in response to welfare issues are shown only on average or by each individual pig. Therefore, this study aimed (1) to quantify the individual variation in feeding behaviour changes in response to a range of welfare issues, and (2) to explain this individual variation by quantifying the responses to welfare issues for specific subgroups of pigs. We monitored four rounds of 110 growing-finishing pigs each (3-4 months per round). We collected feeding behaviour data using IVOG® EFSs and identified health issues and heat stress using climate sensors and twice-weekly health observations. For each pig, a generalised additive model was fitted, which modelled feeding behaviour through time and estimated the effect of each welfare issue that the pig had suffered from. The range of these effect estimates was compared between pigs to study the individual variation in responses. Subsequently, pigs were repeatedly grouped using physical and feeding characteristics, and, with meta-subset analysis, it was determined for each group whether a deviation in response to the welfare issue (i.e. their combined effect estimates) was present. We found that the range in effect estimates was very large, approaching normal distributions for most combinations of welfare issues and feeding variables. This indicates that most pigs did not show feeding behaviour deviations during the welfare issue, while those that did could show both increases and reductions. One exception was heat stress, for which almost all pigs showed reductions in their feed intake, feeding duration and feeding frequency. When looking at subgroups of pigs, it was seen that especially for lameness and tail damage pigs with certain physical characteristics or feeding strategies did consistently deviate on some feeding components during welfare issues (e.g. only relatively heavier pigs reduced their feeding frequency during lameness). In conclusion, while detection of individual pigs suffering from heat stress using feeding variables should be feasible, detection of (mild) health issues would be difficult due to pigs responding differently, if at all, to a given health issue. For some pigs with specific physical or behavioural characteristics, nevertheless, detection of some health issues, such as lameness or tail damage, may be possible.
Collapse
Affiliation(s)
- J D Bus
- Animal Production Systems Group, Wageningen University & Research, PO Box 338, 6700AH Wageningen, the Netherlands.
| | - I J M M Boumans
- Animal Production Systems Group, Wageningen University & Research, PO Box 338, 6700AH Wageningen, the Netherlands
| | - D E Te Beest
- Biometris, Wageningen University & Research, PO Box 16, 6700AA Wageningen, the Netherlands
| | - L E Webb
- Animal Production Systems Group, Wageningen University & Research, PO Box 338, 6700AH Wageningen, the Netherlands
| | - E A M Bokkers
- Animal Production Systems Group, Wageningen University & Research, PO Box 338, 6700AH Wageningen, the Netherlands
| |
Collapse
|
2
|
Segura J, Calvo L, Escudero R, Rodríguez AI, Olivares Á, Jiménez-Gómez B, López-Bote CJ. Alleviating Heat Stress in Fattening Pigs: Low-Intensity Showers in Critical Hours Alter Body External Temperature, Feeding Pattern, Carcass Composition, and Meat Quality Characteristics. Animals (Basel) 2024; 14:1661. [PMID: 38891708 PMCID: PMC11171127 DOI: 10.3390/ani14111661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 05/27/2024] [Accepted: 05/29/2024] [Indexed: 06/21/2024] Open
Abstract
Heat stress is a significant environmental problem that has a detrimental impact on animal welfare and production efficiency in swine farms. The current study was conducted to assess the effect of low-intensity showers, provided during critical high-temperature hours daily, on body external temperature, feeding pattern, and carcass and meat quality characteristics in fattening pigs. A total of 400 animals (200 barrows and 200 gilts) were randomly allotted in 40 pens. A shower nozzle was installed over 20 pens (half barrows and half gilts) where pigs received a low-intensity shower for 2 min in 30 min intervals from 12 to 19 h (SHO group). Another group without showers was also considered (CON). Feeder occupancy measurement, thermographic measures, and carcass and meat quality parameters were studied. In the periods with higher environmental temperatures, SHO animals showed an increase in the feeder occupancy rate compared to the CON group. A decrease in temperature was observed after the shower, regardless of the anatomical location (p < 0.005). The treatment with showers led to higher values than in the CON group of 4.72%, 3.87%, 11.8%, and 15.1% for hot carcass weight, lean meat yield, and fat thickness in Longissimus Dorsi (LD) and Gluteus Medius muscles, respectively (p < 0.01). Pork from CON showed a 14.9% higher value of drip loss, and 18.9% higher malondialdehyde concentration than SHO (p < 0.01); meanwhile, intramuscular fat content was 22.8% higher in SHO than in CON (p < 0.01). On the other hand, the CON group exhibited higher L* (2.13%) and lower a* and b* values (15.8% and 8.97%) compared to the SHO group. However, the pH20h of the CON group was significantly lower than that of the SHO group (p < 0.001), indicating a softer pH decrease. Related to fatty acids in subcutaneous outer and inner layers and intramuscular fat, the CON group showed higher ΣSFA and lower ΣMUFA and Δ9-desaturase indexes than SHO (p < 0.05). In conclusion, the amelioration of heat stress through showers at critical times should be considered an interesting tool that improves both carcass and meat quality, as well as animal welfare.
Collapse
Affiliation(s)
- José Segura
- Food Technology Department, Faculty of Veterinary Medicine, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (L.C.); (B.J.-G.)
| | - Luis Calvo
- Food Technology Department, Faculty of Veterinary Medicine, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (L.C.); (B.J.-G.)
- Incarlopsa, N-400, Km 95.4, 16400 Tarancón, Spain;
- Animal Production Department, Faculty of Veterinary Medicine, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (R.E.); (Á.O.); (C.J.L.-B.)
| | - Rosa Escudero
- Animal Production Department, Faculty of Veterinary Medicine, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (R.E.); (Á.O.); (C.J.L.-B.)
| | - Ana Isabel Rodríguez
- Incarlopsa, N-400, Km 95.4, 16400 Tarancón, Spain;
- Animal Production Department, Faculty of Veterinary Medicine, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (R.E.); (Á.O.); (C.J.L.-B.)
| | - Álvaro Olivares
- Animal Production Department, Faculty of Veterinary Medicine, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (R.E.); (Á.O.); (C.J.L.-B.)
| | - Beatriz Jiménez-Gómez
- Food Technology Department, Faculty of Veterinary Medicine, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (L.C.); (B.J.-G.)
- Incarlopsa, N-400, Km 95.4, 16400 Tarancón, Spain;
| | - Clemente José López-Bote
- Animal Production Department, Faculty of Veterinary Medicine, Complutense University of Madrid, Av. Puerta de Hierro s/n, 28040 Madrid, Spain; (R.E.); (Á.O.); (C.J.L.-B.)
| |
Collapse
|
3
|
Bus JD, Boumans IJMM, Engel J, Te Beest DE, Webb LE, Bokkers EAM. Circadian rhythms and diurnal patterns in the feed intake behaviour of growing-finishing pigs. Sci Rep 2023; 13:16021. [PMID: 37749122 PMCID: PMC10519948 DOI: 10.1038/s41598-023-42612-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 09/12/2023] [Indexed: 09/27/2023] Open
Abstract
The feeding behaviour of growing-finishing pigs is an important indicator of performance, health and welfare, but this use is limited by its large, poorly-understood variation. We explored the variation in basal feed intake of individual pigs by detecting circadian rhythms, extracting features of diurnal patterns and assessing consistency over time, from day-to-day and across age. Hourly feed intake data of individual pigs (n = 110) was obtained during one growing-finishing phase, using electronic feeding stations. We applied wavelet analysis to assess rhythms and a hurdle generalised additive model to extract features of diurnal patterns. We found that circadian rhythms could be detected during 58 ± 3% (mean ± standard error) of days in the growing-finishing phase (range 0-100%), predominantly at older ages. Although the group diurnal intake pattern was alternans (small morning peak, larger afternoon peak), individual pigs showed a range of diurnal patterns that changed with age, differing mostly in the extent of night fasting and day-to-day consistency. Our results suggest that the type, day-to-day consistency and age development of diurnal patterns in feed intake show general group patterns but also differ between pigs. Using this knowledge, promising features may be selected to compare against production, health and welfare parameters.
Collapse
Affiliation(s)
- Jacinta D Bus
- Animal Production Systems Group, Wageningen University & Research, PO Box 338, 6700AH, Wageningen, The Netherlands.
| | - Iris J M M Boumans
- Animal Production Systems Group, Wageningen University & Research, PO Box 338, 6700AH, Wageningen, The Netherlands
| | - Jasper Engel
- Biometris, Wageningen University & Research, PO Box 16, 6700AA, Wageningen, The Netherlands
| | - Dennis E Te Beest
- Biometris, Wageningen University & Research, PO Box 16, 6700AA, Wageningen, The Netherlands
| | - Laura E Webb
- Animal Production Systems Group, Wageningen University & Research, PO Box 338, 6700AH, Wageningen, The Netherlands
| | - Eddie A M Bokkers
- Animal Production Systems Group, Wageningen University & Research, PO Box 338, 6700AH, Wageningen, The Netherlands
| |
Collapse
|
4
|
Contreras-Jodar A, Escribano D, Cerón JJ, López-Arjona M, Aymerich P, Soldevila C, Fàbrega E, Dalmau A. Reducing Stocking Densities and Using Cooling Systems for More Adapted Pigs to High Temperatures When Reared in Intensive Conditions. Animals (Basel) 2023; 13:2424. [PMID: 37570232 PMCID: PMC10416855 DOI: 10.3390/ani13152424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 07/20/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
This study is aimed at evaluating the effect of reducing stocking density and using cooling systems to mitigate the negative effects of high temperatures in growing pigs (females and castrated males) reared in intensive conditions (from 25 to 100 kg) during summer (June to October 2020). The experimental design was a 2 × 2 factorial where pigs were provided with an evaporative cooling system and/or raised at regular or at lower stocking densities (i.e., 0.68 to 0.80 m2/animal). Treatments were distributed in four different rooms containing sex-balanced pens with either castrated males or females. Temperature and humidity were recorded throughout the experiment, and the temperature-humidity index was calculated. Heat stress (HS) on pigs was measured through changes in animals' performance, animal-based indicators (dirtiness and activity budget) and physiological indicators (neutrophil/lymphocyte ratio and hair cortisol). The use of cooling, lowering stocking density and the combination of both strategies had positive effects on pigs' final body weight (+5 kg, +3 kg, +9 kg, respectively; p < 0.001). The prevalence of dirtiness was similar at the stocking densities tested, and no clear effect of the cooling system was found. Both mitigation strategies lowered the physiological indicators of stress, although only hair cortisone can be considered an indicator of HS. In conclusion, both mitigation strategies are effective in improving pig welfare and performance, especially when both are combined. The severity of the stocking density effect may depend on the severity of the temperature.
Collapse
Affiliation(s)
- Alexandra Contreras-Jodar
- Animal Welfare Program, Institute of Agrifood Research and Technology (IRTA), 17121 Monells, Spain; (A.C.-J.); (E.F.)
| | - Damián Escribano
- Interdisciplinary Laboratory of Clinical Analysis, Interlab-UMU, Regional Campus of International Excellence Campus Mare Nostrum, University of Murcia, 30100 Murcia, Spain; (D.E.); (J.J.C.)
| | - José Joaquin Cerón
- Interdisciplinary Laboratory of Clinical Analysis, Interlab-UMU, Regional Campus of International Excellence Campus Mare Nostrum, University of Murcia, 30100 Murcia, Spain; (D.E.); (J.J.C.)
| | - Marina López-Arjona
- Department of Animal and Food Science, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain;
| | - Pau Aymerich
- Vall Companys Group, 25191 Lleida, Spain; (P.A.); (C.S.)
| | | | - Emma Fàbrega
- Animal Welfare Program, Institute of Agrifood Research and Technology (IRTA), 17121 Monells, Spain; (A.C.-J.); (E.F.)
| | - Antoni Dalmau
- Animal Welfare Program, Institute of Agrifood Research and Technology (IRTA), 17121 Monells, Spain; (A.C.-J.); (E.F.)
| |
Collapse
|
5
|
Feeding Behavior of Finishing Pigs under Diurnal Cyclic Heat Stress. Animals (Basel) 2023; 13:ani13050908. [PMID: 36899763 PMCID: PMC10000165 DOI: 10.3390/ani13050908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/06/2023] Open
Abstract
The impact of cyclic heat stress (CHS) and turning the lights on and off on pig feeding behavior (FB) was investigated. The FB of 90 gilts was recorded in real-time under two ambient temperatures (AT): thermoneutrality (TN, 22 °C) or CHS (22/35 °C). The day was divided into four periods: PI (06-08 h); PII (08-18 h); PIII (18-20 h); and PIV (20-06 h). Automatic and Intelligent Precision Feeders recorded each feed event for each pig. An estimated meal criterion (49 min) was used to calculate the FB variables. Feed behavior in both ATs followed a circadian pattern. The CHS reduced the feed intake by 6.9%. The pigs prioritized feed intake during the coolest hours of the day; however, nocturnal cooling did not allow the pigs to compensate for the reduced meal size due to CHS. The highest meal size and most of the meals were observed during the lighting-on period. The pigs reduced their interval between meals during PII and PIII. The lighting program increased the meal size when the lights were switched on and reduced the meal size when the lights were switched off. Thus, the dynamics of the FB were largely influenced by AT, whereas the meal size was affected by the lighting program.
Collapse
|
6
|
José Karpeggiane de Oliveira M, Diego Brandão Melo A, Alves Marçal D, Alves da Cunha Valini G, Alisson Silva C, Mari Veira A, Zem Fraga A, Righetti Arnaut P, Henrique Reis Furtado Campos P, Sousa dos Santos L, Khun Kyaw Htoo J, Gastmann Brand H, Hauschild L. Effects of lowering dietary protein content without or with increased protein-bound and feed-grade amino acids supply on growth performance, body composition, metabolism, and acute-phase protein of finishing pigs under daily cyclic heat stress. J Anim Sci 2023; 101:skac387. [PMID: 36420675 PMCID: PMC9833036 DOI: 10.1093/jas/skac387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 11/17/2022] [Indexed: 11/25/2022] Open
Abstract
This study investigated the effects of a low-protein diet with or without an increase in dietary protein and feed-grade amino acids (AAs) on the growth performance, body composition, metabolism, and serum acute-phase proteins of finishing pigs reared in thermoneutrality or cyclic heat stress conditions. A total of 90 gilts (67.7 ± 6.2 kg) were distributed in a 2 × 3 factorial arrangement (two ambient temperatures and three diets). Ambient temperatures (AT) were thermoneutral (TN, 22 °C for 24 h) and cyclic heat stress (CHS, 12 h to 35 °C and 12 h to 22 °C). The evaluated diets (D) were high crude protein (HP); low CP-free AA-supplemented diets (LPAAs); low CP-free AA-supplemented diets and digestible Lys level (+20%), and Lys:AA ratios above recommendations (LPAA+). The experimental period lasted 48 d (two experimental phases: days 0-27 and days 28-48, respectively). CHS pigs had higher skin temperature (P < 0.05) than TN pigs. Pigs in CHS had higher rectal temperature (P < 0.05) than TN pigs until day 38 but similar (P > 0.10) to TN pigs from 38 to 45 d. For the entire experiment, CHS pigs had lower (P < 0.05) final BW, average daily gain and daily feed intake, net energy intake, body lipid, bone mineral, lipid deposition, energy retention, Lys and CP intake, and nitrogen excretion than TN pigs. The level of CP intake impacted nitrogen excretion, nitrogen retention efficiency, and urea as pigs fed HP had the highest values, and pigs fed LPAA had the lowest values (P < 0.05). On day 27, CHS pigs had lower (P < 0.05) free triiodothyronine than TN pigs. LPAA+ pigs had lower (P < 0.05) insulin than LPAA. On day 48, CHS pigs had lower (P < 0.05) thyroxine, albumin, and lactate than TN pigs. On day 27, pigs fed LPAA+ had higher (P < 0.05) lactate than pigs fed HP or LPAA. Both AT and D were enough to stimulate the immune system as CHS pigs had lower (P < 0.05) transferrin and 23-kDa protein levels than TN pigs, and HP pigs had higher haptoglobin than LPAA on day 27. These results confirm the deleterious effects of high AT on performance, body composition, metabolism, and immune system stimulation in finishing pigs. These data also show that a diet with low levels of CP can be provided to pigs in CHS without affecting performance and body composition while reducing nitrogen excretion. However, the use of a diet with an AA level above the requirements obtained by increasing intact protein and free AA did not attenuate the impact of CHS on performance and body composition of pigs.
Collapse
Affiliation(s)
- Marllon José Karpeggiane de Oliveira
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Antonio Diego Brandão Melo
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Danilo Alves Marçal
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Graziela Alves da Cunha Valini
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Cleslei Alisson Silva
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Alini Mari Veira
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Alícia Zem Fraga
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Pedro Righetti Arnaut
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | | | - Luan Sousa dos Santos
- Department of Animal Nutrition and Pastures, Federal Rural University of Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | | | | | - Luciano Hauschild
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| |
Collapse
|
7
|
Hu C, Patil Y, Gong D, Yu T, Li J, Wu L, Liu X, Yu Z, Ma X, Yong Y, Chen J, Gooneratne R, Ju X. Heat Stress-Induced Dysbiosis of Porcine Colon Microbiota Plays a Role in Intestinal Damage: A Fecal Microbiota Profile. Front Vet Sci 2022; 9:686902. [PMID: 35300220 PMCID: PMC8921775 DOI: 10.3389/fvets.2022.686902] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 01/24/2022] [Indexed: 12/30/2022] Open
Abstract
The pathological mechanisms of gastrointestinal disorders, including inflammatory bowel disease (IBD), in pigs are poorly understood. We report the induction of intestinal inflammation in heat-stressed (HS) pigs, fecal microbiota transplantation from pigs to mice, and explain the role of microorganisms in IBD. 24 adult pigs were subjected to HS (34 ± 1 °C; 75–85% relative humidity for 24h) while 24 control pigs (CP) were kept at 25 ± 3°C and the same humidity. Pigs were sacrificed on days 1, 7, 14, 21. Colonic content microbiome analyses were conducted. Pseudo-germ-free mice were fed by gavage with fecal microbiota from HS-pigs and CP to induce pig-like responses in mice. From 7 d, HS-pigs exhibited fever and diarrhea, and significantly lower colonic mucosal thickness, crypt depth/width, and goblet cell number. Compared with each control group, the concentration of cortisol in the peripheral blood of HS pigs gradually increased, significantly so on days 7, 14, and 21 (P < 0.01). While the concentration of LPS in HS pigs' peripheral blood was significantly higher on days 7, 14 (P < 0.01), and 21 (P < 0.05) compared with that of the control group. The colonic microbiome composition of HS-pigs was different to that of CP. By day 14, opportunistic pathogens (e.g., Campylobacterales) had increased in HS-pigs. The composition of the colonic microbiome in mice administered feces from HS-pigs was different from those receiving CP feces. Bacteroides were significantly diminished, Akkermansia were significantly increased, and intestinal damage and goblet cell numbers were higher in mice that received HS-pig feces. Moreover, we verified the relevance of differences in the microbiota of the colon among treatments. Heat stress promotes changes in gut microbiome composition, which can affect the colonic microbial structure of mice through fecal microbiota transplantation; the molecular mechanisms require further investigation. This study enhanced our understanding of stress-induced inflammation in the colon and the increase in diarrhea in mammals subjected to prolonged HS. Our results provide useful information for preventing or ameliorating deficits in pig production caused by prolonged exposure to high temperatures.
Collapse
Affiliation(s)
- Canying Hu
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
- Shenzhen Institute of Guangdong Ocean University, Shenzhen, China
| | - Yadnyavalkya Patil
- Department of Wine, Food and Molecular Biosciences, Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, New Zealand
| | - Dongliang Gong
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
| | - Tianyue Yu
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
| | - Junyu Li
- Department of Veterinary Medicine, College of Agriculture, Guangdong Ocean University, Zhanjiang, China
| | - Lianyun Wu
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
| | - Xiaoxi Liu
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
| | - Zhichao Yu
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
| | - Xinbing Ma
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
| | - Yanhong Yong
- Department of Veterinary Medicine, College of Agriculture, Guangdong Ocean University, Zhanjiang, China
| | - Jinjun Chen
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
| | - Ravi Gooneratne
- Department of Wine, Food and Molecular Biosciences, Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, New Zealand
| | - Xianghong Ju
- Department of Animal Science, Agricultural College, Guangdong Ocean University, Zhanjiang, China
- Shenzhen Institute of Guangdong Ocean University, Shenzhen, China
- Department of Veterinary Medicine, College of Agriculture, Guangdong Ocean University, Zhanjiang, China
- *Correspondence: Xianghong Ju
| |
Collapse
|
8
|
Ortega ADSV, Babinszky L, Ozsváth XE, Oriedo OH, Szabó C. The Effect of Heat Stress and Vitamin and Micro-Mineral Supplementation on Some Mineral Digestibility and Electrolyte Balance of Pigs. Animals (Basel) 2022; 12:386. [PMID: 35158709 PMCID: PMC8833424 DOI: 10.3390/ani12030386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/01/2022] [Accepted: 02/02/2022] [Indexed: 02/04/2023] Open
Abstract
Heat stress (HS) can have detrimental effects on intestinal integrity and can jeopardize the digestibility performance in pigs. With prolonged exposure to heat, some thermoregulatory processes in pigs are potential causes for electrolyte imbalance. The adverse effects of HS on mineral digestibility and electrolyte balance are not widely studied and information on its abatement through vitamin and micro-mineral supplementation in combinations above the recommended level in pigs is limited. The aim of this study is to research this area. Thirty-six Danbred hybrid barrows (65.1 ± 2.81kg) were distributed among the four treatments (n = 9 per treatment): (1) thermo-neutral (19.5 ± 0.9 °C, RH- 85.9 ± 7.3%)+ control diet (TC) (NRC, 2012), (2) HS (28.9 ± 0.9 °C, RH- 60.4 ± 4.3%) + control diet (HC), (3) HS +diet with elevated levels of vitamins (vitamin E and C) and micro-minerals (Zn and Se) (HT1), and (4) HS + diet with further elevation of vitamins and micro-minerals (HT2). Plasma samples were collected on days 7 and 21 of the experiment to investigate electrolyte concentration. During the experimental period, feces samples were collected from pigs placed in digestibility cages (six pigs from each treatment) to investigate the digestibility of Ca, P, Na, Se, and Zn. HS did not decrease the digestibility of minerals, but elevated supplementation of the selected vitamins and trace minerals improved it significantly. HS caused a significant decrease of Cl- (p < 0.01) in plasma, indicating an imbalance. In conclusion, pigs can have some resilience against heat stress in terms of mineral digestibility. Proper vitamin and trace mineral supplementation are key factors in the ability of pigs to overcome the negative effects of HS.
Collapse
Affiliation(s)
- Arth David Sol Valmoria Ortega
- Department of Animal Nutrition and Physiology, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Animal Science Biotechnology and Nature, University of Debrecen, Böszörményi Street 138, 4032 Debrecen, Hungary; (A.D.S.V.O.); (L.B.)
- Doctoral School of Animal Science, University of Debrecen, Böszörményi Street 138, 4032 Debrecen, Hungary
| | - László Babinszky
- Department of Animal Nutrition and Physiology, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Animal Science Biotechnology and Nature, University of Debrecen, Böszörményi Street 138, 4032 Debrecen, Hungary; (A.D.S.V.O.); (L.B.)
| | - Xénia Erika Ozsváth
- Doctoral School of Animal Science, University of Debrecen, Böszörményi Street 138, 4032 Debrecen, Hungary
- Department of Animal Science, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Animal Science Biotechnology and Nature, University of Debrecen, Böszörményi Street 138, 4032 Debrecen, Hungary;
| | - Ogonji Humphrey Oriedo
- Department of Agriculture, Livestock and Food Security, Veterinary Services Section, County Government of Makueni, Makueni 78-90300, Kenya;
| | - Csaba Szabó
- Department of Animal Nutrition and Physiology, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Animal Science Biotechnology and Nature, University of Debrecen, Böszörményi Street 138, 4032 Debrecen, Hungary; (A.D.S.V.O.); (L.B.)
| |
Collapse
|
9
|
Fraga AZ, Hauschild L, Henrique Reis Furtado Campos P, Valk M, Zava Bello D, Kipper M, Andretta I. Genetic selection modulates feeding behavior of group-housed pigs exposed to daily cyclic high ambient temperatures. PLoS One 2022; 17:e0258904. [PMID: 35073329 PMCID: PMC8786115 DOI: 10.1371/journal.pone.0258904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/07/2021] [Indexed: 11/29/2022] Open
Abstract
This study was conducted to evaluate the effect of genetic selection (Lines A and B; Line A pigs have a greater proportion of Pietrain genes than those from Line B and therefore, selected for improved lean tissue accretion) on the feeding behavior of group-housed pigs exposed to daily cyclic high ambient temperatures. Feeding behavior of 78 barrows housed together in a single room was recorded in real time by five automatic feeders. The feeders registered each visit of each pig (day, hour, min, and second) and the amount of feed requested. Daily cyclic high ambient temperature was induced exposing pigs at 22°C from 18.00 to 10.00 h and 30°C from 10.01 to 17.59 h. From this temperature variation, day-period was divided into: 22°C(06-10h), from 6.00 to 10.00 h; 30°C(10-18h), from 10.01 to 17.59 h; and 22°C(18-06h), from 18.00 to 5.59 h. Meal criteria was estimated based on the probability of animals starting a new feeding event within the next minute since the last visit (Pstart). After defining the meal criteria, the number of meals (n), feed intake rate (g/min), feed intake (g/meal), feeder occupancy (min/meal), and interval between meals (min) of each animal were calculated. Greatest probability of starting to feed was observed at 22°C(06-10h), followed by 30°C(10-18h) and then 22°C(18-06h). Regardless of time period, pigs from line A had greater feed intake rate and lower feed intake, feed occupancy per meal and probability of starting a meal when compared with line B pigs. Only line A pigs had greater feed intake and feeder occupancy per meal at 22°C(18-06h) than remainder of the day. This indicates that pig feeding pattern is strongly related to the circadian rhythm. However, the genetic selection for improved lean tissue accretion may modulate pigs feeding behavior under daily cyclic high ambient temperatures.
Collapse
Affiliation(s)
- Alícia Zem Fraga
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
- PEGASE, INRAE, Institut Agro, Saint Gilles, France
| | - Luciano Hauschild
- Department of Animal Science, School of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | | | - Marcio Valk
- Department of Statistics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Débora Zava Bello
- Department of Statistics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Marcos Kipper
- Department of Animal Science, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Ines Andretta
- Department of Animal Science, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| |
Collapse
|
10
|
Plasticity of feeding behaviour traits in response to production environment (temperate vs. tropical) in group-housed growing pigs. Sci Rep 2022; 12:847. [PMID: 35039563 PMCID: PMC8764086 DOI: 10.1038/s41598-021-04752-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 12/28/2021] [Indexed: 11/08/2022] Open
Abstract
Heat stress affects pig metabolism, health and welfare, resulting in reduced growth and important economic losses. The present experiment aimed to evaluate the effects of two climatic environments [temperate (TEMP) vs. tropical humid (TROP)] on feeding behaviour in growing pigs. The feeding behaviour traits were measured with automated feeders and included: daily feed intake, daily eating time, feeding rate, daily number of meals, feed intake per meal, and feeding time per meal. Pigs came from a backcross population between Large White (LW, heat sensitive) and Creole (CR, heat tolerant) pigs. The same 10 F1 LW × CR boars (sire families [SF]) were mated with related LW sows in each environment. Feeding behaviour was recorded for a total of 1,296 pigs (n = 634 pigs for TEMP and n = 662 pigs for TROP) between 11 and 23 weeks of age. Growth performance and thermoregulatory responses (rectal and skin temperatures) were also measured. Results show that TROP conditions affect feeding behaviour traits: animals had more meals per day but these meals were smaller both in duration and in size, resulting in lower daily feed intake and less time eating per day. Significant SF by environment (GxE) interactions were found for all feeding behaviour traits. When SF were distributed into robust and sensitive groups (previously defined according to performance and thermoregulatory traits), results showed group by environment interactions for all feeding traits, except meal frequency. Moreover, a significant difference in feeding rate between robust and sensitive group was detected in TEMP, suggesting that feeding rate may be a good candidate to evaluate heat tolerance.
Collapse
|
11
|
Abstract
Globally, the climate is changing, and this has implications for livestock. Climate affects livestock growth rates, milk and egg production, reproductive performance, morbidity, and mortality, along with feed supply. Simultaneously, livestock is a climate change driver, generating 14.5% of total anthropogenic Greenhouse Gas (GHG) emissions. Herein, we review the literature addressing climate change and livestock, covering impacts, emissions, adaptation possibilities, and mitigation strategies. While the existing literature principally focuses on ruminants, we extended the scope to include non-ruminants. We found that livestock are affected by climate change and do enhance climate change through emissions but that there are adaptation and mitigation actions that can limit the effects of climate change. We also suggest some research directions and especially find the need for work in developing country settings. In the context of climate change, adaptation measures are pivotal to sustaining the growing demand for livestock products, but often their relevance depends on local conditions. Furthermore, mitigation is key to limiting the future extent of climate change and there are a number of possible strategies.
Collapse
|
12
|
Gourdine JL, Rauw WM, Gilbert H, Poullet N. The Genetics of Thermoregulation in Pigs: A Review. Front Vet Sci 2021; 8:770480. [PMID: 34966808 PMCID: PMC8711629 DOI: 10.3389/fvets.2021.770480] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 11/19/2021] [Indexed: 12/02/2022] Open
Abstract
Heat stress (HS) affects pig performance, health and welfare, resulting in a financial burden to the pig industry. Pigs have a limited number of functional sweat glands and their thermoregulatory mechanisms used to maintain body temperature, are challenged by HS to maintain body temperature. The genetic selection of genotypes tolerant to HS is a promising long-term (adaptation) option that could be combined with other measures at the production system level. This review summarizes the current knowledge on the genetics of thermoregulation in pigs. It also discusses the different phenotypes that can be used in genetic studies, as well as the variability in thermoregulation between pig breeds and the inheritance of traits related to thermoregulation. This review also considers on-going challenges to face for improving heat tolerance in pigs.
Collapse
Affiliation(s)
| | - Wendy Mercedes Rauw
- Departamento de Mejora Genética Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, INIA-CSIC, Madrid, Spain
| | - Hélène Gilbert
- GenPhySE, Université de Toulouse, INRAE, INP, Castanet Tolosan, France
| | | |
Collapse
|
13
|
Moreira VE, Veroneze R, Teixeira ADR, Campos LD, Lino LFL, Santos GA, Silva BAN, Campos PHRF. Effects of Ambient Temperature on the Performance and Thermoregulatory Responses of Commercial and Crossbred (Brazilian Piau Purebred Sires × Commercial Dams) Growing-Finishing Pigs. Animals (Basel) 2021; 11:ani11113303. [PMID: 34828034 PMCID: PMC8614347 DOI: 10.3390/ani11113303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/10/2021] [Accepted: 11/16/2021] [Indexed: 11/17/2022] Open
Abstract
Simple Summary Physiological responses to heat stress are affected by breed. Therefore, crossbreeding genetically improved lines with tropically adapted breeds of pigs may be a strategy to attenuate the impact of high ambient temperatures on pig production. Although some studies have evaluated thermotolerance in tropically adapted breeds, it is not yet clear to which extent improved tolerance to heat stress is a consequence of a greater ability to equilibrate thermogenesis and thermolysis, or if it is a consequence of decreased growth performance. Although there was no interaction for performance, thermoregulatory responses, and blood parameters, our results evidenced that ambient temperature effects on carcass parameters were modulated by the pigs’ genotype. Because protein deposition significantly decreased in response to high ambient temperature in commercial pigs, and was not affected by ambient temperature in Piau crossbred pigs, our study suggests increased thermotolerance of Piau crossbred pigs. Abstract The study aimed at evaluating the effects of high ambient temperature (HT: 30 °C) on the thermoregulatory responses and performance of commercial and Piau crossbred (Brazilian Piau breed sires × commercial genotype dams) growing pigs. Commercial and Piau crossbred pigs were reared under thermoneutral (TN: 22 °C) or HT conditions during a 14-day experimental period. Feeding (daily) and animals (beginning and end) were weighted to obtain performance parameters. Skin and rectal temperatures, respiratory rate, and blood parameters were also measured. At the end of the trial (day 15), the animal’s backfat thickness (BF) and loin eye area (LEA) were measured. No interaction (p > 0.05) between the genetic group and ambient temperature was observed for any performance trait. Irrespective of ambient temperature, Piau crossbred pigs had a similar feed intake (ADFI, 2615 g/day, on average; p > 0.05), lower daily weight gain (ADG, −234 g/day; p < 0.01), and a higher feed conversion ratio (FCR, +0.675 g/g; p < 0.01). There was interaction (p = 0.01) between genotype and ambient temperature for the LEA that decreased significantly in response to HT in commercial pigs (−6.88 cm2) and did not differ in response to ambient temperature in Piau crossbred pigs (29.14 cm2, on average; p > 0.05). Piau crossbred pigs had greater BF (+7.2 mm; p < 0.01) than commercial pigs. Regardless of the genetic group, exposure of pigs to HT resulted in decreased ADFI (−372 g/day; p < 0.01), ADG (−185 g/day; p < 0.01), and a higher FCR (+0.48 g/g; p = 0.01). Ambient temperature did not affect lipid deposition. Pigs at HT had an increased respiratory rate (+38 bpm; p < 0.01) and a long-lasting increase in skin and rectal temperatures compared to TN pigs. Total concentrations of triiodothyronine (T3) and thyroxine (T4) were not affected by ambient temperature in commercial pigs, whereas Piau crossbred pigs kept at 30 °C had a transient decrease in both hormones at day 2 (p < 0.01). Serum cortisol concentrations were not affected (p > 0.05) by genotype nor ambient temperature. In summary, Piau crossbred pigs had lower efficiency using nutrients for growth in association with increased lipid deposition when compared to commercial pigs. In response to HT, commercial pigs had a decreased LEA, whereas no effect was observed for Piau crossbred pigs. Apart from that, commercial and Piau crossbred pigs had a similar magnitude of thermoregulatory responses activation in response to HT, evidencing their innate survival-oriented function.
Collapse
Affiliation(s)
- Vinícius Eduardo Moreira
- Animal Science Postgraduate Program, Department of Animal Science, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina 39100-000, MG, Brazil; (V.E.M.); (A.d.R.T.)
- Department of Animal Science, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil; (R.V.); (L.D.C.); (L.F.L.L.); (G.A.S.)
| | - Renata Veroneze
- Department of Animal Science, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil; (R.V.); (L.D.C.); (L.F.L.L.); (G.A.S.)
| | - Alípio dos Reis Teixeira
- Animal Science Postgraduate Program, Department of Animal Science, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Diamantina 39100-000, MG, Brazil; (V.E.M.); (A.d.R.T.)
| | - Lorena Duarte Campos
- Department of Animal Science, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil; (R.V.); (L.D.C.); (L.F.L.L.); (G.A.S.)
| | - Lais Fernanda Lopes Lino
- Department of Animal Science, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil; (R.V.); (L.D.C.); (L.F.L.L.); (G.A.S.)
| | - Gabryele Almeida Santos
- Department of Animal Science, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil; (R.V.); (L.D.C.); (L.F.L.L.); (G.A.S.)
| | - Bruno Alexander Nunes Silva
- Institute of Agricultural Sciences, Department of Animal Science, Universidade Federal de Minas Gerais, Montes Claros 39404-547, MG, Brazil;
| | - Paulo Henrique Reis Furtado Campos
- Department of Animal Science, Universidade Federal de Viçosa, Viçosa 36570-900, MG, Brazil; (R.V.); (L.D.C.); (L.F.L.L.); (G.A.S.)
- Correspondence:
| |
Collapse
|
14
|
Effects of heat stress on performance and thermoregulatory responses of Piau purebred growing pigs. J Therm Biol 2021; 99:103009. [PMID: 34420639 DOI: 10.1016/j.jtherbio.2021.103009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 11/24/2022]
Abstract
The study of how different breeds adapt to heat stress and the further understanding of mechanisms underlying pigs thermotolerance is of utmost importance to attenuate the negative effects of heat stress on pigs welfare, physiology, and performance. Therefore, this study aimed at evaluating the effects of ambient temperature on performance and thermoregulatory responses of Piau purebred pigs. The Brazilian native pig breed Piau is a fat-type breed characterized by adaptability and resistance to diseases. To achieve our goal, Piau purebred pigs (65 kg initial BW) were allocated to one of the two constant ambient temperature conditions: thermoneutral (22 °C; n = 11) and heat stress (30 °C; n = 11). The experimental period lasted 15 days (days 1 to 15). Pigs were individually weighed at the beginning and end of the experimental period. Body and rectal temperatures, respiratory rate and blood indicators of stress and metabolism were measured throughout the experiment. Piau purebred pigs exposed to 30 °C had lower (p < 0.05) feed intake, body weight gain and final body weight than pigs at 22 °C. Feed conversion rate was not affected (p > 0.05) by ambient temperature. Irrespective of ambient temperature, pigs had similar (p > 0.05) backfat thickness and loin eye area. Piau pigs at 30 °C had increased (p < 0.05) nape, dorsal, flank, and rectal temperatures and increased respiratory rate than their counterparts reared at 22 °C. In summary, our results show that Piau purebred pigs acclimation to 30 °C of ambient temperature is characterized by increased body skin temperature to optimize sensible heat loss to the environment; increased respiratory rate to promote latent heat loss; and by a concomitant reduced voluntary feed intake to reduce heat production associated with digestion and metabolic processes with negative effects on body weight gain.
Collapse
|
15
|
Bus JD, Boumans IJ, Webb LE, Bokkers EA. The potential of feeding patterns to assess generic welfare in growing-finishing pigs. Appl Anim Behav Sci 2021. [DOI: 10.1016/j.applanim.2021.105383] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
16
|
Early life thermal stress can have long-term impacts on piglets. J Anim Sci 2020; 98:6015753. [PMID: 33260198 DOI: 10.1093/jas/skaa351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 10/23/2020] [Indexed: 11/13/2022] Open
|
17
|
Toward better estimates of the real-time individual amino acid requirements of growing-finishing pigs showing deviations from their typical feeding patterns. Animal 2020; 14:s371-s381. [PMID: 32515319 DOI: 10.1017/s1751731120001226] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Pigs exposed to stressors might change their daily typical feeding intake pattern. The objective of this study was to develop a method for the early identification of deviations from an individual pig's typical feeding patterns. In addition, a general approach was proposed to model feed intake and real-time individual nutrient requirements for pigs with atypical feeding patterns. First, a dynamic linear model (DLM) was proposed to model the typical daily feed intake (DFI) and daily gain (DG) patterns of pigs. Individual DFI and DG dynamics are described by a univariate DLM in conjunction with Kalman filtering. A standardized tabular cumulative sum (CUMSUM) control chart was applied to the forecast errors generated by DLM to activate an alarm when a pig showed deviations from its typical feeding patterns. The relative feed intake (RFI) during a challenge period was calculated. For that, the forecasted individual pig DFI is expressed as its highest DFI relative to the intake during pre-challenge period. Finally, the DLM and RFI approaches were integrated into the actual precision-feeding model (original model) to estimate real-time individual nutrient requirements for pigs with atypical feeding patterns. This general approach was evaluated with data from two studies (130 pigs, at 35.25 ± 3.9 kg of initial BW) that investigated during 84 days the effect of precision-feeding systems for growing-finishing pigs. The proposed general approach to estimating real-time individual nutrient requirements (updated model) was evaluated by comparing its estimates with those generated by the original model. For 11 individuals out of 130, the DLM did not fit the observed data well in a specific period, resulting in an increase in the sum of standardized forecast errors and in the number of time steps that the model needed to adapt to the new patterns. This poor fit can be identified by the increase in the CUMSUM with a consequent alarm generated. The results of this study show that the updated model made it possible to reduce intra-individual variation for the estimated lysine requirements in comparison with the original model, especially for individuals with atypical feeding patterns. In conclusion, the DLM in conjunction with CUMSUM could be used as a tool for the online monitoring of DFI for growing-finishing pigs. Moreover, the proposed general approach allows the estimation of real-time amino acid requirements and accounts for the reduced feed intake and growth potential of pigs with atypical feeding patterns.
Collapse
|