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Saleem M, Yousuf MR, Ghafoor A, Riaz A. Effect of three schemes of ovum pick-up on the follicular dynamics, gene expression, and in-vitro developmental competence of oocytes in Sahiwal cattle. Reprod Domest Anim 2022; 57:1230-1243. [PMID: 35771838 DOI: 10.1111/rda.14198] [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: 05/13/2022] [Revised: 06/16/2022] [Accepted: 06/28/2022] [Indexed: 12/31/2022]
Abstract
This study aimed to compare the effect of three schemes of ovum pick-up (OPU) on follicular dynamics, oocytes recovery, oocytes quality, gene expression, nuclear maturation and in-vitro developmental competence of oocytes in Sahiwal cattle. Considering the follicle population, all the cows were divided equally in a 3 × 3 cross over design, and each cow received one of the three treatments: (a) twice weekly (TW; n = 6), (b) once weekly (OW; n = 6) and (c) bi-weekly OPU (BW; n = 6) in three periods, with the first OPU conducted on 4, 7 and 14 days after second dominant follicle puncture (DFP) in the TW, OW and BW OPU interval groups, respectively. The collected cumulus oocytes complexes (COCs) were graded into A, B, C and D grades depending on the number of layers of cumulus cells and homogeneous nature of cytoplasm. Nuclear maturation was assessed by staining the oocytes with Hoechst 33342. The growth rate (mm/day) of dominant follicle (DF) (F1) (0.49 ± 0.21 vs. 0.71 ± 0.26 vs. 1.30 ± 0.27) and first subordinate follicle (F2) (0.85 ± 0.27 vs. 0.71 ± 0.25 vs. 1.06 ± 0.29) did not differ (p > .05) among all the three groups. The proportion of animals bearing a corpus luteum (CL) in the BW OPU interval group (53.3%) was significantly higher (p < .05) as compared to TW (13.3%) and OW (18.3%) OPU interval groups. The number of medium-sized follicles and oocyte with grade A and B were significantly higher (p < .05) in the TW (1.16 ± 0.21 and 33.88 ± 0.03) OPU interval group as compared to the OW (0.88 ± 0.22 and 21.54 ± 0.03) and BW (0.55 ± 0.21 and 21.89 ± 0.02) OPU interval groups. However, the number of degenerated oocytes in BW (0.85 ± 0.16) OPU interval group was significantly higher (p < .05) as compared to the TW (0.16 ± 0.15) and OW (0.44 ± 0.16) OPU interval groups. Expression level of growth differentiation factor 9 in TW OPU interval group was significantly higher (p < .05) as compared to the OW and BW OPU interval groups. Likewise, expression level of bone morphogenetic protein 15 (BMP15) in the TW and BW OPU interval groups was significantly higher (p < .05) as compared to the OW OPU interval group. The nuclear maturation rate was significantly higher in the TW (63.64 ± 0.07) and BW (59.26 ± 0.08) OPU groups as compared to OW (51.43 ± 0.06) OPU interval group. However, the cleavage rate (59.30 ± 0.06 vs. 44.29 ± 0.06 vs. 56.67 ± 0.06) did not differ (p > .05) among the three groups. Whereas, the blastocyst rate tended to be higher (p = .06) in the TW (29.07 ± 0.05) and BW (28.33 ± 0.04) OPU interval groups as compared to OW (18.57 ± 0.05) OPU interval group. Taken together, it can be concluded that TW OPU interval scheme enhances the medium-sized follicles resulting in good quality oocytes, regulates the oocyte-derived paracrine factors, leading to higher nuclear maturation rates and improved embryonic development in-vitro.
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Affiliation(s)
- Muhammad Saleem
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Rizwan Yousuf
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Aamir Ghafoor
- Department of Microbiology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Amjad Riaz
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
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Keshri A, Roy D, Kumar V, Kumar M, Kushwaha R, Vaswani S, L. VK, Dixit S, Prakash A, Choudhury S. Impact of different chromium sources on physiological responses, blood biochemicals and endocrine status of heat stress in dairy calves. BIOL RHYTHM RES 2019. [DOI: 10.1080/09291016.2019.1628390] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Anchal Keshri
- Animal Nutrition Division, ICAR-National Dairy Research Institute, Karnal, India
| | - Debashis Roy
- Department of Animal Nutrition, College of Veterinary and Animal Science, SVPUAT, Meerut University, Meerut, India
| | - Vinod Kumar
- Department of Animal Nutrition, College of Veterinary Science and Animal Husbandry, DUVASU, Mathura University, Mathura, India
| | - Muneendra Kumar
- Department of Animal Nutrition, College of Veterinary Science and Animal Husbandry, DUVASU, Mathura University, Mathura, India
| | - Raju Kushwaha
- Department of Animal Nutrition, College of Veterinary Science and Animal Husbandry, DUVASU, Mathura University, Mathura, India
| | - Shalini Vaswani
- Department of Animal Nutrition, College of Veterinary Science and Animal Husbandry, DUVASU, Mathura University, Mathura, India
| | - Vandana Kumari L.
- Animal Nutrition Division, ICAR-National Dairy Research Institute, Karnal, India
| | - Sonam Dixit
- Animal Nutrition Division, ICAR-National Dairy Research Institute, Karnal, India
| | - Atul Prakash
- Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, DUVASU, Mathura University, Mathura, India
| | - Soumen Choudhury
- Department of Veterinary Pharmacology and Toxicology, College of Veterinary Science and Animal Husbandry, DUVASU, Mathura University, Mathura, India
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Romo-Barron CB, Diaz D, Portillo-Loera JJ, Romo-Rubio JA, Jimenez-Trejo F, Montero-Pardo A. Impact of heat stress on the reproductive performance and physiology of ewes: a systematic review and meta-analyses. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2019; 63:949-962. [PMID: 30888508 DOI: 10.1007/s00484-019-01707-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 02/25/2019] [Accepted: 03/04/2019] [Indexed: 06/09/2023]
Abstract
High values of ambient temperature and relative humidity negatively affect livestock because they induce heat stress. In heat-stressed ewes, the reproduction is affected, although there apparently is a different effect depending on their physiological status. Therefore, we conducted a systematic review and meta-analyses to estimate the effect of heat stress on the reproductive performance and physiology of cycling or pregnant ewes. We included studies in which pregnant or cycling ewes were exposed to heat stress and included a comparison group. We assessed the risk of bias and used meta-analyses that included the period of exposure to calculate pooled estimates. We included 36 studies comprising 20,626 ewes, and the meta-analyses demonstrated that heat stress decreased 7.09 h (95% CI, - 10.75, - 3.43) the duration of estrus in cycling ewes but increased 0.57 days (95% CI, 0.23, 0.92) the length of the cycle, although differentially affecting the expression of sexual behavior. Heat-stressed cycling ewes had greater odds of embryo mortality (OR = 12.36; 95% CI, 7.10, 21.54) and a decreased chance of impregnation (OR = 0.41; 95% CI, 0.23, 0.75). In heat-stressed pregnant ewes, placental and fetal weights were reduced, respectively in 183.62 g (95%CI, - 252.25, - 114.99) and 1665.18 g (95% CI, - 2136.82, - 1193.55). Heat stress increased ewes' body temperature 1.13 °C (95% CI, 0.85, 1.42) and respiratory rate 93.53 breaths/min (95% CI, 63.5, 123.5) without affecting heart rate. In a sub-group analyses, the period of exposure was shown to cause a significant effect. In conclusion, our results revealed a differential effect of heat stress that depends on both the physiological status of ewes and the period of exposure, and identify susceptible reproductive stages during which the severe effects of heat stress can be prevented/ameliorated.
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Affiliation(s)
- Cinthya B Romo-Barron
- Laboratorio de Reproducción Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Sinaloa, Boulevard San Ángel 3886, Predio Las Coloradas, 80246, Culiacán Rosales, Sinaloa, Mexico
| | - Daniel Diaz
- Laboratorio de Reproducción Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Sinaloa, Boulevard San Ángel 3886, Predio Las Coloradas, 80246, Culiacán Rosales, Sinaloa, Mexico
- Centro de Ciencias de la Complejidad (C3), Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, Mexico City, Mexico
| | - Jesus J Portillo-Loera
- Laboratorio de Reproducción Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Sinaloa, Boulevard San Ángel 3886, Predio Las Coloradas, 80246, Culiacán Rosales, Sinaloa, Mexico
| | - Javier A Romo-Rubio
- Laboratorio de Reproducción Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Sinaloa, Boulevard San Ángel 3886, Predio Las Coloradas, 80246, Culiacán Rosales, Sinaloa, Mexico
| | | | - Arnulfo Montero-Pardo
- Laboratorio de Reproducción Animal, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Sinaloa, Boulevard San Ángel 3886, Predio Las Coloradas, 80246, Culiacán Rosales, Sinaloa, Mexico.
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Sánchez-Dávila F, Ungerfeld R, Bosque-González ASD, Bernal-Barragán H. Seasonality in Saint Croix male lamb reproductive development in northern Mexico. Reprod Domest Anim 2018; 54:391-400. [DOI: 10.1111/rda.13372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Accepted: 11/01/2018] [Indexed: 11/29/2022]
Affiliation(s)
| | - Rodolfo Ungerfeld
- Departamento de Fisiología, Facultad de Veterinaria; Universidad de la República; Montevideo Uruguay
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Pragna P, Sejian V, Bagath M, Krishnan G, Archana PR, Soren NM, Beena V, Bhatta R. Comparative assessment of growth performance of three different indigenous goat breeds exposed to summer heat stress. J Anim Physiol Anim Nutr (Berl) 2018; 102:825-836. [PMID: 29582479 DOI: 10.1111/jpn.12892] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 02/25/2018] [Indexed: 11/29/2022]
Abstract
A study was conducted to assess comparatively the growth performance of three different indigenous goat breeds during exposure to summer heat stress. The primary objective of the study was to observe the heat stress impact on the growth performance based on the body weight changes, allometric measurements, growth hormone (GH) concentration and peripheral blood mononuclear cell (PBMC) Insulin-like growth factor-1 (IGF-1) mRNA expression pattern during the summer season in comparison with the local breed (Osmanabadi). Thirty-six ten-month- to one-year-old female goats of Osmanabadi, Malabari and Salem Black breeds were randomly divided into six groups, OC (n = 6; Osmanabadi control), OHS (n = 6; Osmanabadi heat stress), MC (n = 6; Malabari control), MHS (n = 6; Malabari heat stress), SBC (n = 6; Salem Black control) and SBHS (n = 6; Salem Black heat stress). Body weight was recorded at weekly intervals, whereas other growth and allometric measurements and blood collection were carried out at fortnightly intervals. Breed factor significantly (p < .05) influenced only few growth variables such as body weight, body mass index (BMI) and body condition score (BCS). However, heat stress treatment significantly (p < .05) reduced all growth parameters expect BMI. Further, the heat stress significantly (p < .01) increased plasma GH concentration in goats with significantly higher (p < .05) concentration recorded in OHS. Among the stress groups, the lower (p < .05) PBMC IGF-1 mRNA expression was recorded in OHS, while the higher (p < .05) expression was observed in SBHS indicating the extreme adaptive capability of Salem Black breed. Thus, the results indicated that the Salem Black breed performed much better compared to both Osmanabadi and Malabari breeds indicating the superior ability of this breed to adapt to heat stress challenges. The results also indicated that plasma GH and IGF-1 gene may act as ideal biomarkers for assessing the heat stress impact on growth performance in indigenous goats.
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Affiliation(s)
- P Pragna
- ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bangalore, India.,Academy of Climate Change Education and Research, Kerala Agricultural University, Vellanikkara, Thrissur, Kerala, India.,Centre for Animal Adaptation to Environment and Climate Change Studies, Kerala Veterinary and Animal Sciences University, Mannuthy, Thrissur, Kerala, India
| | - V Sejian
- ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bangalore, India
| | - M Bagath
- ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bangalore, India
| | - G Krishnan
- ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bangalore, India
| | - P R Archana
- ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bangalore, India.,Academy of Climate Change Education and Research, Kerala Agricultural University, Vellanikkara, Thrissur, Kerala, India.,Centre for Animal Adaptation to Environment and Climate Change Studies, Kerala Veterinary and Animal Sciences University, Mannuthy, Thrissur, Kerala, India
| | - N M Soren
- ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bangalore, India
| | - V Beena
- Centre for Animal Adaptation to Environment and Climate Change Studies, Kerala Veterinary and Animal Sciences University, Mannuthy, Thrissur, Kerala, India
| | - R Bhatta
- ICAR-National Institute of Animal Nutrition and Physiology, Adugodi, Bangalore, India
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Effect of thermal exposure on physiological adaptability and seminal attributes of rams under semi-arid environment. J Therm Biol 2017; 65:113-118. [DOI: 10.1016/j.jtherbio.2017.02.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 02/24/2017] [Indexed: 11/15/2022]
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Macías-Cruz U, Gastélum MA, Álvarez FD, Correa A, Díaz R, Meza-Herrera CA, Mellado M, Avendaño-Reyes L. Effects of summer heat stress on physiological variables, ovulation and progesterone secretion in Pelibuey ewes under natural outdoor conditions in an arid region. Anim Sci J 2015; 87:354-60. [DOI: 10.1111/asj.12430] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 02/23/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Ulises Macías-Cruz
- Instituto de Ciencias Agrícolas; Universidad Autónoma de Baja California; Valle de Mexicali México
| | - Miguel A. Gastélum
- Instituto de Ciencias Agrícolas; Universidad Autónoma de Baja California; Valle de Mexicali México
| | - Francisco D. Álvarez
- Instituto de Ciencias Agrícolas; Universidad Autónoma de Baja California; Valle de Mexicali México
| | - Abelardo Correa
- Instituto de Ciencias Agrícolas; Universidad Autónoma de Baja California; Valle de Mexicali México
| | - Raúl Díaz
- Facultad de Medicina; Universidad Autónoma de Baja California; Mexicali B.C. México
| | - César A. Meza-Herrera
- Unidad Regional Universitaria de Zonas Áridas; Universidad Autónoma Chapingo; Bermejillo Durango México
| | - Miguel Mellado
- Departamento de Nutrición Animal; Universidad Autónoma Agraria “Antonio Narro”; Saltillo Coahuila México
| | - Leonel Avendaño-Reyes
- Instituto de Ciencias Agrícolas; Universidad Autónoma de Baja California; Valle de Mexicali México
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Indu S, Sejian V, Naqvi SMK. Impact of simulated heat stress on growth, physiological adaptability, blood metabolites and endocrine responses in Malpura ewes under semiarid tropical environment. ANIMAL PRODUCTION SCIENCE 2015. [DOI: 10.1071/an14085] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The study was conducted to develop a simulated heat stress model for sheep depicting natural environmental conditions and to observe its impact on growth, reproductive performance, physiological adaptability, blood metabolites and endocrine responses in Malpura ewes. The experiment was conducted on 16 adult Malpura ewes for a period of 35 days. The animals were randomly divided into two groups of eight animals each (GI – control, GII – heat stress). The GII ewes were exposed to different temperature at different hours of the day i.e. 38°C at 1000–1100 hours; 40°C at 1100–1200 hours; 42°C at 1200–1300 hours; 43°C at 1300–1400 hours; 44°C at 1400–1500 hours and 42°C at 1500–1600 hours in a climatic chamber. Feed intake (P < 0.01), bodyweight (P < 0.05) and body condition score (P < 0.01) reduced significantly in GII as compared with GI ewes while water intake increased significantly (P < 0.01). All physiological responses also showed significant variation between the groups for treatment. In addition, all endocrine parameters showed highly significant (P < 0.01) variation for the treatment. Plasma cortisol increased significantly (P < 0.01) while T3 (P < 0.01) and T4 (P < 0.01) decreased significantly in GII as compared with GI ewes. Further, plasma oestradiol decreased significantly (P < 0.01) while plasma progesterone increased significantly (P < 0.01) in GII as compared with GI. Among the biochemical parameters, hemoglobin, packed cell volume, plasma glucose, total cholesterol, urea and blood urea nitrogen differed significantly between the groups. In addition, oestrus duration also significantly (P < 0.05) reduced in GII as compared with GI. Based on the results obtained from the study it can be concluded that simulated heat stress influenced the adaptive behaviour of sheep in terms of changes in physiological, blood biochemical and endocrine responses. Ultimately, their growth and reproductive performance are compromised during the process of adaptation to the simulated heat stress.
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Abstract
Stressors, such as poor body condition, adverse temperatures or even common management procedures (e.g., transport or shearing) suppress normal oestrus behaviour and reduce ewe fertility. All these events are co-ordinated by endocrine interactions, which are disrupted in stressful situations. This disruption is usually temporary in adult ewes, so that, when prevailing conditions improve, normal fertility would resume. Imposition of an experimental stressor (shearing, transport, isolation from other sheep, injection of endotoxin or insulin or cortisol infusion) suppresses GnRH/LH pulse frequency and amplitude. Part of the cause is at the pituitary, but effects on GnRH/LH pulse frequency and the GnRH/LH surge are mediated via the hypothalamus. It is not yet clear whether delays in the surge are caused by interruption of the oestradiol signal-reading phase, the signal transmission phase or GnRH surge release. Stressors also delay the onset of behaviour, sometimes distancing this from the onset of the pre-ovulatory LH surge. This could have deleterious consequences for fertility.
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Affiliation(s)
- H Dobson
- School of Veterinary Science, University of Liverpool, Leahurst Campus, Neston, Wirral, United Kingdom.
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Sejian V, Maurya VP, Naqvi SMK. Adaptive capability as indicated by endocrine and biochemical responses of Malpura ewes subjected to combined stresses (thermal and nutritional) in a semi-arid tropical environment. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2010; 54:653-661. [PMID: 20607306 DOI: 10.1007/s00484-010-0341-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Revised: 05/23/2010] [Accepted: 06/04/2010] [Indexed: 05/29/2023]
Abstract
A study was conducted to assess the effect of combined stresses (thermal and nutritional) on endocrine and biochemical responses in Malpura ewes. Twenty eight adult Malpura ewes (average body weight 33.56 kg) were used in the present study. The ewes were divided into four groups viz., GI (n = 7; control), GII (n = 7; thermal stress), GIII (n = 7; nutritional stress) and GIV (n = 7; combined stress). The animals were stall fed with a diet consisting of 60% roughage and 40% concentrate. GI and GII ewes were provided with ad libitum feeding while GIII and GIV ewes were provided with restricted feed (30% intake of GI ewes) to induce nutritional stress. GII and GIV ewes were kept in climatic chamber at 40°C and 55% RH for 6 h a day between 1000 hours and 1600 hours to induce thermal stress. The study was conducted for a period of two estrus cycles. The parameters studied were Hb, PCV, glucose, total protein, total cholesterol, ACP, ALP, cortisol, T(4), T(3), and insulin. Combined stress significantly (P < 0.05) affected all parameters studied. Furthermore, the results revealed that, compared to thermal stress, nutritional stress had a less significant effect on the parameters studied. However, when both these stresses were coupled, they had a severe impact on all the parameters studied in these ewes. It can be concluded from this study that two stressors occurring simultaneously may impact severely on the biological functions necessary to maintain homeostasis in sheep.
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Affiliation(s)
- Veerasamy Sejian
- Adaptation Physiology Laboratory, Division of Physiology & Biochemistry, Central Sheep and Wool Research Institute, Avikanagar, Tonk District, Rajasthan 304501, India.
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Sejian V, Maurya VP, Naqvi SMK. Effect of thermal stress, restricted feeding and combined stresses (thermal stress and restricted feeding) on growth and plasma reproductive hormone levels of Malpura ewes under semi-arid tropical environment. J Anim Physiol Anim Nutr (Berl) 2010; 95:252-8. [PMID: 20796074 DOI: 10.1111/j.1439-0396.2010.01048.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A study was conducted to assess the effect of thermal, nutritional and combined stresses (thermal and nutritional) on the growth, oestradiol and progesterone levels during oestrus cycles in Malpura ewes. Twenty-eight adult Malpura ewes were used in the present study. The ewes were randomly allocated into four groups, viz., GI (n=7; control), GII (n=7; thermal stress), GIII (n=7; restricted feeding) and GIV (n=7; combined stress). The animals were stall fed with a diet consisting of 60% roughage and 40% concentrate. GI and GII ewes were provided with ad libitum feeding while GIII and GIV ewes were provided with restricted feed (30% intake of GI and GII ewes) to induce nutritional insufficiency. GII and GIV ewes were kept in climatic chamber at 40°C and 55% RH for 6 h a day between 10:00 and 16:00 hours to induce thermal stress for a period of two oestrous cycles. Parameters studied were body weight, oestrus incidences, plasma oestradiol 17-β, plasma progesterone, conception rate, gestation period, lambing rate, and birth weight of lambs. The results indicate that combined stress significantly (p<0.05) reduced body weight, oestrus duration, birth weight of lambs, and oestradiol 17-β whereas significantly (p < 0.05) increased oestrus cycle length and progesterone. Furthermore, the results reveal that on comparative basis, ewes were able to better adapt in terms of growth and reproduction to restricted feeding than thermal stress. However, when restricted feeding was coupled with thermal stress it had significant (p<0.05) influence on body weight, average daily gain, oestradiol 17-β and progesterone concentrations. This showed that combined stress were more detrimental for these reproductive hormones in Malpura ewes under a hot semi-arid environment.
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Affiliation(s)
- V Sejian
- Adaptation Physiology Laboratory, Division of Physiology & Biochemistry, Central Sheep & Wool Research Institute, Avikanagar, Rajasthan, India
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