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Hassanein EM, Szelényi Z, Szenci O. Gonadotropin-Releasing Hormone (GnRH) and Its Agonists in Bovine Reproduction II: Diverse Applications during Insemination, Post-Insemination, Pregnancy, and Postpartum Periods. Animals (Basel) 2024; 14:1575. [PMID: 38891622 PMCID: PMC11171120 DOI: 10.3390/ani14111575] [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: 04/01/2024] [Revised: 05/17/2024] [Accepted: 05/23/2024] [Indexed: 06/21/2024] Open
Abstract
The administration of GnRH and its agonists benefits various aspects of bovine reproductive programs, encompassing physiological stages such as estrous synchronization, post-insemination, pregnancy, and the postpartum period. The positive impact of GnRH administration in overcoming challenges like repeat breeder cows, early embryonic loss prevention, and the management of cystic ovarian disease (COD) is thoroughly surveyed. Furthermore, this review focuses on the significance of GnRH administration during the postpartum period, its role in ovulation induction, and how it enhances the productivity of embryo transfer (ET) programs. An emerging feature of this field is introduced, focusing on nano-drug delivery systems for GnRH agonists, and the potential benefits that may arise from such advancements are highlighted. While this review offers valuable insights into various applications of GnRH in bovine reproduction, it emphasizes the crucial need for further research and development in this field to advance reproductive efficiency and health management in dairy cattle.
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Affiliation(s)
- Eman M. Hassanein
- Department of Obstetrics and Food Animal Medicine Clinic, University of Veterinary Medicine Budapest, H-2225 Üllő, Hungary; (E.M.H.); (Z.S.)
- Animal and Fish Production Department, Faculty of Agriculture, Alexandria University, Alexandria 21545, Egypt
| | - Zoltán Szelényi
- Department of Obstetrics and Food Animal Medicine Clinic, University of Veterinary Medicine Budapest, H-2225 Üllő, Hungary; (E.M.H.); (Z.S.)
| | - Ottó Szenci
- Department of Obstetrics and Food Animal Medicine Clinic, University of Veterinary Medicine Budapest, H-2225 Üllő, Hungary; (E.M.H.); (Z.S.)
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Uddin AHMM, Petrovski KR, Song Y, Garg S, Kirkwood RN. Application of Exogenous GnRH in Food Animal Production. Animals (Basel) 2023; 13:1891. [PMID: 37370402 PMCID: PMC10295615 DOI: 10.3390/ani13121891] [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: 05/04/2023] [Revised: 05/29/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
Over several decades, exogenous GnRH and agonists have been employed for controlling reproductive cascades in animals, and treating some reproductive morbidities. The administration of GnRH is used in animals to counter ovarian dysfunction, induce ovulation, and to increase conception and pregnancy rates. GnRH and its agonists are used in the treatment of cystic ovarian degeneration and repeat breeder syndrome. The development of protocols for GnRH administration by intramuscular injection, intramuscular or subcutaneous implants, and intravaginal deposition has empowered their clinical use worldwide. Currently, exogenous GnRH products are a central part of several pre- and post-breeding programs for the enhancement of fertility, including the control of estrous cycles and timing of ovulation, development of fixed-time artificial insemination protocols, improved embryo survival, and the treatment of reproductive morbidity. The aim of the present review is to summarize the application of exogenous GnRH agonists in food animal production.
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Affiliation(s)
- A. H. M. Musleh Uddin
- School of Animal & Veterinary Sciences, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia;
| | - Kiro R. Petrovski
- Davies Livestock Research Centre, School of Animal & Veterinary Sciences, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia;
- Australian Centre for Antimicrobial Resistance Ecology, School of Animal & Veterinary Sciences, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia
| | - Yunmei Song
- Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia; (Y.S.); (S.G.)
| | - Sanjay Garg
- Clinical and Health Sciences, University of South Australia, Adelaide, SA 5000, Australia; (Y.S.); (S.G.)
| | - Roy N. Kirkwood
- School of Animal & Veterinary Sciences, University of Adelaide, Roseworthy Campus, Roseworthy, SA 5371, Australia;
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Abulaiti A, Naseer Z, Liu W, Ahmed Z, Abdelrahman M, Shaukat A, Pang X, Wang S. Administration of GnRH at day 20 of AI and embryonic losses in synchronized crossbred buffalo. Front Vet Sci 2023; 10:1118865. [PMID: 36908523 PMCID: PMC9995848 DOI: 10.3389/fvets.2023.1118865] [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: 12/08/2022] [Accepted: 02/02/2023] [Indexed: 02/25/2023] Open
Abstract
Introduction Following the application of different artificial insemination and synchronization protocols, the synchronized buffaloes had a higher incidence of early embryonic or fetal death, thus impairing reproductive performance. Therefore, there is a need to devise a synchronizing program that can improve conception, allow early pregnancy diagnosis, reduce early embryonic losses, and provide an early clue for pregnancy diagnosis and establishment. The present study aimed (1) to determine the effect of administration of different GnRH doses at day 20 of artificial insemination (AI) on the reproductive performance of buffaloes and (2) to observe the influence of synchronization protocol, parity, age, milk production, and body condition score (BCS) on early embryonic loss and progesterone (P4) levels in crossbred buffaloes. Methods Crossbred buffaloes (n = 101) were synchronized using the GPGMH protocol. At day 20 of AI, the synchronized buffaloes were randomly divided into four groups and administrated GnRH doses (0, 100, 150, and 200 μg). The buffaloes were monitored for ovarian dynamics, P4 level, non-return rate, embryonic/fetal losses, and pregnancy rates. The previously synchronized buffaloes were also classified for synchronization protocol (with or without GnRH), parity (nulli- or multiparous), milk production (high or low), BCS (low, medium, or good) or age (>3 or < 3 years) groups for observing the embryonic loss and P4 level variations. Results The results indicated no difference (P > 0.05) in CL size, P4 level, pregnancy rate and embryo/fetal losses across the treatment groups at different observation periods. There was a high (P < 0.05) incidence of early embryonic mortality in aged, multiparous, low BCS and low milk-producing buffaloes treated without GnRH. Conclusion The data suggest that GnRH 200 μg at day 20 of AI improves embryo survival and pregnancy maintenance in crossbred buffaloes.
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Affiliation(s)
- Adili Abulaiti
- College of Animal Science, Anhui Science and Technology University, Chuzhou, Anhui, China.,Anhui Province Key Laboratory of Animal Nutritional Regulation and Health, Chuzhou, Anhui, China
| | - Zahid Naseer
- Faculty of Veterinary and Animal Sciences, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Pakistan
| | - Wenju Liu
- College of Life and Health Science, Anhui Science and Technology University, Chuzhou, Anhui, China
| | - Zulfiqar Ahmed
- Key Laboratory of Swine Genetics and Breeding of Ministry of Agriculture and Rural Affairs, and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan, China
| | - Mohamed Abdelrahman
- Animal Production Department, Faculty of Agriculture, Assiut University, Asyut, Egypt
| | - Aftab Shaukat
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xunsheng Pang
- College of Animal Science, Anhui Science and Technology University, Chuzhou, Anhui, China
| | - Shujuan Wang
- College of Animal Science, Anhui Science and Technology University, Chuzhou, Anhui, China.,Anhui Province Key Laboratory of Animal Nutritional Regulation and Health, Chuzhou, Anhui, China
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Pacelli C, Barile VL, Sabia E, Casano AB, Braghieri A, Martina V, Barbato O. Use of GnRH Treatment Based on Pregnancy-Associated Glyco-Proteins (PAGs) Levels as a Strategy for the Maintenance of Pregnancy in Buffalo Cows: A Field Study. Animals (Basel) 2022; 12:ani12202822. [PMID: 36290208 PMCID: PMC9597821 DOI: 10.3390/ani12202822] [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: 09/07/2022] [Revised: 10/02/2022] [Accepted: 10/13/2022] [Indexed: 11/23/2022] Open
Abstract
The aim of the study was to evaluate the effects of GnRH administrated at day 35 after artificial insemination (AI) on the reproductive performance of buffalo cows. In ten buffalo farms in the period January−February, 481 buffalo cows were subjected to estrus synchronization protocol and fixed-time artificial insemination (Ovsynch−TAI program). Radioimmunoassays (RIA) for pregnancy-associated glycoproteins (PAGs) were used to detect pregnancy at day 28 after AI (cut-off value: ≥1 ng/mL). Among pregnant subjects, those with PAG values between 1 and 2.5 ng/mL were considered at risk of embryonic mortality (EM) and were assigned into two groups: treated (T; n = 57) control (C; n = 57). Treated buffaloes received 0.01 mg of buserelin acetate intramuscularly on day 35 after AI, whereas control buffaloes received no treatment. The pregnancy diagnosis was confirmed at day 60 through PAGs level and rectal palpation. The treatment with GnRH had a significant effect (p < 0.001) in reducing EM. Between days 28 and 60 after AI, the animals that experienced EM were only 2/57 in the T group, while were 13/57 in the C group. Moreover, GnRH treatment produced a significant increase (p < 0.001) in the PAG concentration between day 28 and day 60. Administration of GnRH at day 35 after AI in animals considered at risk of low embryo survival based on PAG levels allowed a reduction in pregnancy losses and improved the pregnancy rate during low-breeding season in buffalo.
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Affiliation(s)
- Corrado Pacelli
- School of Agricultural, Forest, Food, and Environmental Sciences, University of Basilicata, 85100 Potenza, Italy
| | - Vittoria Lucia Barile
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria (CREA)—Research Centre for Animal Production and Aquaculture, 00015 Rome, Italy
| | - Emilio Sabia
- School of Agricultural, Forest, Food, and Environmental Sciences, University of Basilicata, 85100 Potenza, Italy
| | | | - Ada Braghieri
- School of Agricultural, Forest, Food, and Environmental Sciences, University of Basilicata, 85100 Potenza, Italy
| | - Valeria Martina
- School of Agricultural, Forest, Food, and Environmental Sciences, University of Basilicata, 85100 Potenza, Italy
| | - Olimpia Barbato
- Department of Veterinary Medicine, University of Perugia, 06126 Perugia, Italy
- Correspondence: ; Tel.: +39-075-585-7640; Fax: +39-075-585-7638
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Neglia G, de Nicola D, Esposito L, Salzano A, D'Occhio MJ, Fatone G. Reproductive management in buffalo by artificial insemination. Theriogenology 2020; 150:166-172. [PMID: 31982156 DOI: 10.1016/j.theriogenology.2020.01.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 01/11/2020] [Indexed: 10/25/2022]
Abstract
Artificial insemination (AI) is important for genetic improvement and to control the period of breeding in buffalo and has increased significantly over the past 20 years. AI is more difficult in buffalo compared with cattle due to variable estrous cycles, reduced estrous behavior, and reproductive seasonality. The latter is associated with a higher incidence of anestrus and increased embryonic mortality during the nonbreeding season. Protocols to control the stage of the estrous cycle have undergone recent development in buffalo. These protocols are based on the control of both the luteal phase of the cycle, mainly by prostaglandins and progesterone, and follicle development and ovulation, by prostaglandins, progesterone, GnRH, hCG, eCG and estradiol. Protocols that synchronize the time of ovulation enable fixed timed AI, avoiding estrous detection. Factors to consider when selecting an AI protocol include animal category (heifers, primiparous or pluriparous), reproductive status (cyclic or anestrus), and season. This review looks at the current status of estrus synchronization and AI in buffalo and provides some practical suggestions for application of AI in the field.
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Affiliation(s)
- Gianluca Neglia
- Department of Veterinary Medicine and Animal Production, Federico II University of Naples, Via F. Delpino 1, 80137, Napoli, NA, Italy.
| | - Donato de Nicola
- Department of Veterinary Medicine and Animal Production, Federico II University of Naples, Via F. Delpino 1, 80137, Napoli, NA, Italy
| | - Luigi Esposito
- Department of Veterinary Medicine and Animal Production, Federico II University of Naples, Via F. Delpino 1, 80137, Napoli, NA, Italy
| | - Angela Salzano
- Department of Veterinary Medicine and Animal Production, Federico II University of Naples, Via F. Delpino 1, 80137, Napoli, NA, Italy
| | - Michael John D'Occhio
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Gerardo Fatone
- Department of Veterinary Medicine and Animal Production, Federico II University of Naples, Via F. Delpino 1, 80137, Napoli, NA, Italy
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Ahmad N, Arshad U. Synchronization and resynchronization strategies to improve fertility in dairy buffaloes. Theriogenology 2020; 150:173-179. [PMID: 31982154 DOI: 10.1016/j.theriogenology.2020.01.025] [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] [Received: 01/11/2020] [Accepted: 01/12/2020] [Indexed: 11/26/2022]
Abstract
Dairy buffalo has an integral role in the sustenance of economics due to its substantial contribution in milk and meat industry, however, the reproduction in this species is challenging. During the last decade, our laboratory conducted a series of experiments to encapsulate the solutions of the problems through optimizing pre- and post-insemination interventions in dairy buffaloes. In an unique study, we proposed that timing of ovulation with reference to the onset of standing heat during spontaneous estrus is delayed, and subsequently re-framed the traditional AM-PM rule (AI after 12 h of standing heat) to AM-AM or PM-PM (AI after 24 h of standing heat) to achieve the optimum fertility using frozen thawed semen in dairy buffaloes. Pregnancy per AI (P/AI) varied substantially either via injecting single shot of prostaglandin (PG) F2α to perform AI at detected estrus or applying standard ovsynch protocol for timed AI (TAI) in buffaloes. However, estrus response, and P/AI remained similar either with used or new controlled internal drug release device in dairy buffaloes. Additionally, the incorporation of estradiol benzoate in progesterone (P4) based protocol resulted in controlled emergence of follicular wave and increased the estrus intensity in buffaloes. Thereafter, we fine-tuned P4-based protocols to optimize the ovulation window for TAI either using GnRH or human chorionic gonadotropin (hCG) or equine chorionic gonadotropin that ultimately improved the fertility in dairy buffaloes. Although, these hormonal interventions resulted in decent fertility, yet it was consistently being compromised due to early or late embryonic losses in dairy buffaloes. Administration of hCG or GnRH on d 7 or 23 or 25 post AI has been proved beneficial to enhance the embryonic survival in buffaloes. Recently, resynchronization program as an aggressive reproductive management approach has been tested that served as a dual-purpose tool to increase overall herd fertility and reduce embryonic losses at commercial buffalo farm operations. Taken together, we concluded that the solutions to the problems of reproductive function are now clearly available with acceptable fertility, however, their application to the small holder buffalo farming remains challenging.
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Affiliation(s)
- Nasim Ahmad
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, 54000, Punjab, Pakistan.
| | - Usman Arshad
- Department of Animal Sciences, University of Florida, Gainesville, 32611, Florida, USA
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Resynchronisation as an Element of Improving Cattle Reproduction Efficiency. J Vet Res 2019; 63:107-115. [PMID: 30989142 PMCID: PMC6458552 DOI: 10.2478/jvetres-2019-0009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 02/12/2019] [Indexed: 01/07/2023] Open
Abstract
Oestrus resynchronisation (RES, Resynch) programmes for non-pregnant cows allow shortening the period between an unsuccessful insemination and the next attempt on the same cow. The protocol of oestrus RES may be started after ruling out pregnancy by means of ultrasonography carried out 28 days after insemination or after performing a test for pregnancy-specific glycoproteins (PAG) in blood or milk. The Resynch protocol can be based on a double application of prostaglandins, the OvSynch protocol, or hormonal therapy with exogenous sources of progesterone (CIDR intravaginal devices). The efficiency of the method depends on the functional state of the ovaries, the diameter of the corpus luteum, external factors, and the health and maturity of the cows. The present paper constitutes a comparison of research findings concerning the effectiveness of RES programmes.
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Riaz U, Hassan M, Husnain A, Naveed MI, Singh J, Ahmad N. Effect of timing of artificial insemination in relation to onset of standing estrus on pregnancy per AI in Nili-Ravi buffalo. Anim Reprod 2018; 15:1231-1235. [PMID: 34221137 PMCID: PMC8203108 DOI: 10.21451/1984-3143-ar2017-0015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aim of the present study was to determine the optimum time of artificial insemination after
the beginning of standing estrus in buffalo. Nili-Ravi buffalo (n = 109) during breeding season
were exposed to teaser bull at 12 hours interval to determine the standing heat (0 h). Buffalo
were randomly allocated to different time groups and a single artificial insemination was
performed either at 0 h (n = 30), 12 h (n = 27), 24 h (n = 28) or 36 h (n = 24). In a subset of buffalo (n
= 38) ultrasonography was performed, twice daily from 0 h (onset of standing heat) to determine
the time of ovulation. Pregnancy diagnosis was performed 35-40 days after AI. Results revealed
that mean time of ovulation from onset of standing heat was 34.7 ± 0.96 h (range 30 to
42 h). Higher (P < 0.05) pregnancy per AI were achieved in buffalo when inseminated at 24
h (15/28; 53%) compared to 0 h (8/30; 26%) and 36 h (3/24; 13%). Pregnancy per AI, was in-between,
in buffalo, inseminated at 12 h (10/27; 37%) and did not differ (P > 0.05) with those bred
either at 24 h or 0 h. The odds ratio further confirmed that the occurrence of pregnancy per AI
was two times higher in buffalo inseminated at 24 h as compared to those at 12 h. It is concluded
that optimal pregnancy per AI can be achieved when buffalo are bred artificially 24 h after
the onset of standing heat.
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Affiliation(s)
- Umair Riaz
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Mubbashar Hassan
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Ali Husnain
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Muhammad Ilyas Naveed
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Jaswant Singh
- Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Nasim Ahmad
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Pakistan
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Meziane R, Niar A, Boughris F, Meziane T, Mamache B, Smadi MA. Induction of cyclicity in dairy cows using GnRH (Gonadotropin releasing hormone) in the region of Batna, Algeria. BIOL RHYTHM RES 2018. [DOI: 10.1080/09291016.2018.1528687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Rahla Meziane
- Department of Veterinary Sciences, Laboratory Environment, Health and Animal Production (ESPA), University of Batna1, Batna, Algeria
| | - Abdelatif Niar
- Laboratory of Animal Farm Reproduction, National Institute of Veterinary Sciences, Ibn Khaldoun University of Tiaret, Tiaret, Algeria
| | | | - Toufik Meziane
- Department of Veterinary Sciences, Laboratory Environment, Health and Animal Production (ESPA), University of Batna1, Batna, Algeria
| | - Bakir Mamache
- Department of Veterinary Sciences, Laboratory Environment, Health and Animal Production (ESPA), University of Batna1, Batna, Algeria
| | - Mustapha Adnane Smadi
- Department of Veterinary Sciences, Laboratory Environment, Health and Animal Production (ESPA), University of Batna1, Batna, Algeria
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Resynchronization of synchronized follicular wave in dromedary camels of unknown pregnancy status (Camelus dromedarius). Theriogenology 2018; 119:208-213. [DOI: 10.1016/j.theriogenology.2018.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 07/04/2018] [Accepted: 07/05/2018] [Indexed: 11/21/2022]
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Khan AS, Haider MS, Hassan M, Husnain A, Yousuf MR, Ahmad N. Equine chorionic gonadotropin (eCG) enhances reproductive responses in CIDR-EB treated lactating anovular Nili-Ravi buffalo during the breeding season. Anim Reprod Sci 2018; 196:28-34. [DOI: 10.1016/j.anireprosci.2018.06.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 06/09/2018] [Accepted: 06/22/2018] [Indexed: 11/28/2022]
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Qayyum A, Arshad U, Yousuf MR, Ahmad N. Effect of breeding method and season on pregnancy rate and embryonic and fetal losses in lactating Nili-Ravi buffaloes. Trop Anim Health Prod 2017; 50:555-560. [PMID: 29147936 DOI: 10.1007/s11250-017-1468-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 11/06/2017] [Indexed: 01/22/2023]
Abstract
The aim of this study was to determine the effect of breeding method and season on pregnancy rate and cumulative embryonic and fetal losses in Nili-Ravi buffalo. Estrus detection was performed twice a day by teaser buffalo bull for 1 hour each. A 2 × 2 factorial design was used to address the breeding method and season. Buffaloes (n = 130) exhibiting estrus were randomly assigned to be bred either in peak breeding season (PBS; n = 80) or low breeding season (LBS; n = 50). Within each season, buffaloes were divided to receive either natural service (NS; n = 65) or artificial insemination (AI; n = 65). NS buffaloes, in estrus, were allowed to remain with the bull until mating. AI was achieved, using frozen thawed semen of bull of known fertility. PBS comprised of September to December and LBS were from May to July. Serial ultrasonography was performed on days 30, 45, 60, and 90 after breeding (day 0) to monitor pregnancy rate and embryonic and fetal losses. The pregnancy rate on day 30 after breeding was higher in NS as compared to AI group (63 vs. 43%; P < 0.05) during PBS while it did not differ (48 vs. 32%; P > 0.05) in LBS. The cumulative embryonic and fetal losses between days 31 and 90 were significantly lower in PBS than LBS (33 vs. 60%; P < 0.05), ignoring breeding method. Pregnancy rates were better with NS in PBS, and cumulative embryonic fetal losses were higher in LBS in Nili-Ravi buffalo.
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Affiliation(s)
- Arslan Qayyum
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan
| | - Usman Arshad
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan
| | - Muhammad Rizwan Yousuf
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan
| | - Nasim Ahmad
- Department of Theriogenology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, 54000, Pakistan.
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