PSXV-12 What 30 years of accumulated pregnancy data taught us about the Bos indicus influence on reproductive performance of beef cattle. (8th October 2021)
- Record Type:
- Journal Article
- Title:
- PSXV-12 What 30 years of accumulated pregnancy data taught us about the Bos indicus influence on reproductive performance of beef cattle. (8th October 2021)
- Main Title:
- PSXV-12 What 30 years of accumulated pregnancy data taught us about the Bos indicus influence on reproductive performance of beef cattle
- Authors:
- Martins, Thiago
Rocha, Cecilia Constantino
Driver, Joseph D
Rae, Owen
Elzo, Mauricio A
Mateesku, Raluca
Binelli, Mario - Abstract:
- Abstract: Bos taurus X Bos indicus crossbreeding is commonly used in tropical and subtropical regions to enhance beef production. The effect of Bos indicus genetics on pregnancy to AI (P/AI) and AI + natural service (P/AI+NS) is understudied. We measured the indicus effect from a 30-year dataset of the University of Florida multibreed herd (MBH; n= 7105 animals). The MBH is composed of six breed groups, according to the following proportion of Brahman: 0–19%, 20–34%, 37% (Brangus), 40–59%, 60%-78% and 79%-100%. Estrus of all animals was synchronized using mainly the SelectSynch+CIDR protocol, followed by three-day AI based on heat or timed-AI (TAI) for non-heat animals. After TAI, animals were bred by NS. Breeding seasons lasted 91±18d. Pregnancy was diagnosed by rectal palpation and/or ultrasonography 30d after AI and 30d after removal of bulls. P/AI was affected negatively (P < 0.001) by the proportion of Brahman, regardless of parity, but P/AI+NS was similar across breeding groups (Table 1). By logistic regression, each 1/32 nd increment of Brahman influence reduced odds of P/AI by 0.5% (0/32 nd = 51.4% to 32/32 nd = 35.3%). The variables of body condition score (BCS), days post-partum (DPP) and body weight at the beginning of synchronization protocol did not explain the negative effect of indicus genetics on P/AI. However, indicus genetics were associated negatively with the proportion of animals AIed in heat (P < 0.001). AI in heat resulted in twice as great (P < 0.001)Abstract: Bos taurus X Bos indicus crossbreeding is commonly used in tropical and subtropical regions to enhance beef production. The effect of Bos indicus genetics on pregnancy to AI (P/AI) and AI + natural service (P/AI+NS) is understudied. We measured the indicus effect from a 30-year dataset of the University of Florida multibreed herd (MBH; n= 7105 animals). The MBH is composed of six breed groups, according to the following proportion of Brahman: 0–19%, 20–34%, 37% (Brangus), 40–59%, 60%-78% and 79%-100%. Estrus of all animals was synchronized using mainly the SelectSynch+CIDR protocol, followed by three-day AI based on heat or timed-AI (TAI) for non-heat animals. After TAI, animals were bred by NS. Breeding seasons lasted 91±18d. Pregnancy was diagnosed by rectal palpation and/or ultrasonography 30d after AI and 30d after removal of bulls. P/AI was affected negatively (P < 0.001) by the proportion of Brahman, regardless of parity, but P/AI+NS was similar across breeding groups (Table 1). By logistic regression, each 1/32 nd increment of Brahman influence reduced odds of P/AI by 0.5% (0/32 nd = 51.4% to 32/32 nd = 35.3%). The variables of body condition score (BCS), days post-partum (DPP) and body weight at the beginning of synchronization protocol did not explain the negative effect of indicus genetics on P/AI. However, indicus genetics were associated negatively with the proportion of animals AIed in heat (P < 0.001). AI in heat resulted in twice as great (P < 0.001) P/AI (65.4%; n = 984) than no-heat TAI (30.9%; n = 829). In conclusion, indicus genetics did not influence overall pregnancy rates at the end of a 90d breeding season. Nevertheless, indicus influence dampened estrus responses to protocols based solely on GnRH-PGF and progestin/progesterone, resulting on suboptimal P/AI (< 40%). … (more)
- Is Part Of:
- Journal of animal science. Volume 99(2021)Supplement 3
- Journal:
- Journal of animal science
- Issue:
- Volume 99(2021)Supplement 3
- Issue Display:
- Volume 99, Issue 3 (2021)
- Year:
- 2021
- Volume:
- 99
- Issue:
- 3
- Issue Sort Value:
- 2021-0099-0003-0000
- Page Start:
- 236
- Page End:
- 237
- Publication Date:
- 2021-10-08
- Subjects:
- Beef cattle -- Bos indicus -- estrus -- reproduction
Livestock -- Periodicals
Livestock
Electronic journals
Periodicals
636.005 - Journal URLs:
- https://dl.sciencesocieties.org/publications/jas/index ↗
http://www.asas.org/jas/ ↗
https://academic.oup.com/jas ↗
http://www.oxfordjournals.org/ ↗ - DOI:
- 10.1093/jas/skab235.431 ↗
- Languages:
- English
- ISSNs:
- 0021-8812
- Deposit Type:
- Legaldeposit
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- Available online (eLD content is only available in our Reading Rooms) ↗
- Physical Locations:
- British Library DSC - BLDSS-3PM
British Library HMNTS - ELD Digital store - Ingest File:
- 25248.xml