Document Detail

Factors affecting seasonal variation in 90-day nonreturn rate to first service in lactating Holstein cows in a hot climate.
MedLine Citation:
PMID:  10629807     Owner:  NLM     Status:  MEDLINE    
The objective was to determine factors controlling seasonal variation in 90-d nonreturn rate to first service (90-d NRR) including effects of location, milk yield, and weather variables on specific days before and after breeding. Dairy Herd Improvement Association records on first services from 8124 Holstein cows in south Georgia (GA, n = 7 herds), north Florida (NF, n = 5), and south Florida (SF, n = 5) were used. The 90-d NRR was affected by location x month of breeding. The summer drop in 90-d NRR was of lower magnitude and duration in GA than in NF or SF and of lower magnitude and duration for NF than SF. When cows were grouped according to mature equivalent milk yield, there was a milk yield class x month of breeding interaction. As milk yield class increased, the summer depression in 90-d NRR was more pronounced. In a second series of analyses, effects of average air temperature at d -10, 0, and 10 relative to breeding were evaluated with subsets of cows in which average air temperature on the 10 d before the reference day were cool (< 25 degrees C). The 90-d NRR for cows having average temperatures > 20 degrees C on d -10 was less than 90 d NRR for cows with average temperatures < or = 20 degrees C on d -10 (60.1 vs. 36.5%). Similar results were found on d 0 (59.6 vs. 41.4%) and d 10 (56.9 vs. 41.1%). Thus, heat stress before and after breeding, and on the day of breeding, is associated with low 90-d NRR.
Y M al-Katanani; D W Webb; P J Hansen
Related Documents :
8253627 - Isolation of multiple salmonella serovars from a dairy two years after a clinical salmo...
10764057 - The strategic use of estradiol to enhance fertility and submission rates of progestin-b...
7648527 - Evaluation of an o antigen enzyme-linked immunosorbent assay for screening of milk samp...
18765597 - Water intake and dry matter intake changes as a feeding management tool and indicator o...
8848477 - Effect of stress and food variety on food intake in male and female rats.
10349217 - Household food insecurity and hunger among families using food banks.
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Journal of dairy science     Volume:  82     ISSN:  0022-0302     ISO Abbreviation:  J. Dairy Sci.     Publication Date:  1999 Dec 
Date Detail:
Created Date:  2000-01-27     Completed Date:  2000-01-27     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  2985126R     Medline TA:  J Dairy Sci     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  2611-6     Citation Subset:  IM    
Department of Dairy and Poultry Sciences, University of Florida, Gainesville 32611-0920, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cattle / physiology*
Hot Temperature*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  A comparative study of reproductive performance in organic and conventional dairy husbandry.
Next Document:  Short communication: lack of breed differences in responses of bovine spermatozoa to heat shock.