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Bó GA, Menchaca A. Prohibition of hormones in animal reproduction: what to expect and what to do? Anim Reprod 2023; 20:e20230067. [PMID: 37720723 PMCID: PMC10503886 DOI: 10.1590/1984-3143-ar2023-0067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 07/18/2023] [Indexed: 09/19/2023] Open
Abstract
As our understanding of ovarian function in cattle has improved, our ability to control it has also increased. The development of Fixed-Time Artificial Insemination (FTAI) protocols at the end of the 20th century has increased exponentially the number of animals inseminated over the last 20 years. The main reasons for this growth were the possibility of obtaining acceptable pregnancy rates without heat detection and, above all, the induction of cyclicity in suckled cows in postpartum anestrus and prepubertal heifers at the beginning of the breeding season. Most FTAI treatments in South America have been based on the use of progesterone (P4) releasing devices and estradiol to synchronize both follicular wave emergence and ovulation, with pregnancy rates ranging from 40 to 60%. These protocols are implemented on a regular basis, allowing producers access to high-quality genetics, and increasing the overall pregnancy rates during the breeding season. In addition, it provided the professionals involved in these programs with a new source of income and the diversification of their practices into activities other than their usual clinical work. Many of these practices are now apparently at risk from restrictions on the use of estradiol by the European Union (EU) and other countries. However, the development of alternative protocols based on GnRH, with P4 devices and eCG and other new products that are not in the market yet will allow us to adapt to the new times that are coming. Logically, the challenge has already been raised and we must learn to use alternative protocols to try to continue increasing the use of this technology in beef and dairy herds. The objective of the present review is to describe the main aspects of banning estradiol in livestock production, the negative impacts on reproductive efficiency, and to present some alternative FTAI protocols for dairy and beef cattle.
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Affiliation(s)
- Gabriel Amilcar Bó
- Instituto de Reproducción Animal Córdoba, Córdoba, Argentina
- Instituto de Ciencias Básicas, Medicina Veterinaria, Universidad Nacional de Villa María, Villa del Rosario, Córdoba, Argentina
- Fundación Instituto de Reproducción Animal Uruguay, Montevideo, Uruguay
| | - Alejo Menchaca
- Plataforma de Investigación en Salud Animal, Instituto Nacional de Investigación Agropecuaria, Montevideo, Uruguay
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Li H, Sun N, Xiao Y, Yang H, Guo Z, Lin Y, Wang X, Wu Q, Zhou Y, Yang L, Hua G. Benefits of Using Double-Ovsynch Versus Presynch-Ovsynch are Affected by Environmental Heat in Primiparous Holstein Lactating Cows. Anim Reprod Sci 2023; 251:107224. [PMID: 37003063 DOI: 10.1016/j.anireprosci.2023.107224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 03/15/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023]
Abstract
Optimized reproduction management enhances fertility of dairy cows, and thus improves their milk production efficiency. Comparing different synchronization protocols under variable ambient conditions would be conducive to protocol selection and production efficiency improvement. Here, 9538 primiparous Holstein lactating cows were enrolled to either Double-Ovsynch (DO) or Presynch-Ovsynch (PO) to determine the outcomes under different ambiences. We found that averaged THI of 21-days before the first service (THI-b) was the best indicators in a total of 12 environmental indexes to explain changes in conception rate. And the conception rate decreased linearly in DO treated cows when THI-b was over 73, whereas the threshold was 64 in cows subjected to PO. Compared with PO treated cows, DO increased conception rate by 6%, 13% and 19%, when THI-b was lower than 64, from 64 to 73, and over 73, respectively. Furthermore, employing treatment of PO would lead greater risk for cows staying open compared with DO when THI-b below 64 (hazard ratio, 1.3) and over 73 (hazard ratio, 1.4). Most importantly, calving intervals were 15 days shorter in DO treated cows compared PO when THI-b over 73, while no difference was detected when THI-b below 64. In conclusion, our results supported that, fertility of primiparous Holstein cows could be improved by employing DO, especially in hot weather (THI-b ≥ 73), and the benefits of DO protocol were abated under cool conditions (THI-b < 64). Considering the impacts of environmental heat load is necessary to determine reproductive protocols for commercial dairy farm.
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Affiliation(s)
- Huazhao Li
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Nan Sun
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Yao Xiao
- Key Laboratory of Livestock and Poultry Multi-omics of MARA, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan, Shandong 250100, China
| | - Hongzhen Yang
- Wuhan Anscitech Farming Technology Co., Ltd., Wuhan, Hubei 430070, China
| | - Zhigang Guo
- Modern Farming (Group) Co., Ltd., Maanshan, Anhui 243000, China
| | - Yuxin Lin
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Xiaojie Wang
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Qipeng Wu
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Yang Zhou
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Liguo Yang
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Huazhong Agricultural University, Wuhan, Hubei 430070, China; National Center for International Research on Animal Genetics, Breeding and Reproduction, Wuhan, Hubei 430070, China
| | - Guohua Hua
- Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Frontiers Science Center for Animal Breeding and Sustainable Production, Huazhong Agricultural University, Wuhan, Hubei 430070, China; National Center for International Research on Animal Genetics, Breeding and Reproduction, Wuhan, Hubei 430070, China.
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