Reproductive performance as affected by lactation status and body fat in beef cows.

Seventy-one mature Brangus cows, 38 nonlactating (NL) and 33 in late stage of lactation (L) were fed for 192 days (Phase I) a low energy diet (L). During Phase II (65 days) 19 NL and 17 L cows were fed a high energy diet (H). The other nonlactating (19) and lactating (16) cows remained on the low en...

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Bibliographic Details
Authors: GUIMARÃES FILHO, C.; RAY, D. E.
Format: Article
Status:Published version
Publication date:1985
Country:Brasil
Institution:EMBRAPA
Repository:Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
Language:English
OAI Identifier:oai:www.alice.cnptia.embrapa.br:doc/132198
Online Access:http://www.alice.cnptia.embrapa.br/alice/handle/doc/132198
Access Level:Open access
Keyword:Concepcao
Amamentacao
Beff cows
Body lipid
Bovino
Lactação
Produção Animal
Lipídio
Reprodução
animal production
conception
lactation
reproduction
suckling
Description
Summary:Seventy-one mature Brangus cows, 38 nonlactating (NL) and 33 in late stage of lactation (L) were fed for 192 days (Phase I) a low energy diet (L). During Phase II (65 days) 19 NL and 17 L cows were fed a high energy diet (H). The other nonlactating (19) and lactating (16) cows remained on the low energy diet. Energy restriction during Phase I did not affect (P> 0.05) cyclic ovarian activity although losses in body weight and condition were substantial. Rapid changes in body weight, condition, and percent empty body lipe (EBLP) during Phase II did not substantially influencefertility, although a five-fold difference in EBLP was observed (NL0H vs. L-L). Treatment groups did not differ (P> 0.05) in conception rate, days from the beginning of the breeding season to breeding and to conception, conception at first service, and number of services per conception. Values observed for these parameters for NL-H, L-H, NL-L, and L-L groups were respectively: 68,4%, `3,.2, 23.3, 36.8% and 1.68; 82,4% 12.7, 19.5, 58.8% and 1.29; 68.4%, 10.2, 17.4, 47.4%, and 1.41; 68.8%, 12.4, 19.5, 43.7%, and 1.50.