Document Detail


Effects of natural (RRR alpha-tocopherol acetate) or synthetic (all-rac alpha-tocopherol acetate) vitamin E supplementation on reproductive efficiency in beef cows.
MedLine Citation:
PMID:  20495121     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The objective was to determine the effects of natural- or synthetic-source vitamin E on reproductive efficiency in Angus-cross beef cows. In Exp. 1, one hundred fifty-two cows were fed hay and corn silage based diet and assigned to 1 of 3 dietary supplements (3 pens/treatment): 1) containing no additional vitamin E (CON), 2) formulated to provide 1,000 IU x d(-1) of synthetic-source vitamin E (SYN; all-rac or dl-alpha-tocopherol acetate), or 3) formulated to provide 1,000 IU x d(-1) of natural-source vitamin E (NAT; RRR or D-alpha-tocopherol acetate). In Exp. 2, seventy-five cows (2 reps/treatment) were assigned to similar treatments as Exp. 1; however, a vitamin-mineral supplement was offered for ad libitum intake and vitamin intake was calculated from predicted mineral intakes. Cows grazed pastures rather than being fed hay and corn silage as in Exp. 1. In Exp. 1 and 2, supplementation began 6 wk prepartum and continued until initiation of the breeding season. Blood samples were collected at calving (Exp. 1) or breeding (Exp. 2) to determine alpha-tocopherol concentration and weekly beginning 4 wk postpartum (Exp. 1) or 7 and 14 d before estrus synchronization (Exp. 2) to determine return to estrus via progesterone concentration. Cows were synchronized and bred by AI based on heat detection; nonresponding cows were time bred (AI) 66 h after PGF(2 alpha) injection, and cows returning to estrus after AI were bred by natural service. In Exp. 1, cows supplemented with NAT and SYN had greater (P < 0.001) serum concentrations of alpha-tocopherol at calving compared with CON cows. Dietary supplement did not affect (P >or= 0.55) the percentage of cows cycling before synchronization or the number of days to return to estrus by cows that resumed estrus before synchronization. Cows supplemented with SYN tended to have greater first service conception rates compared with CON and NAT (P = 0.09); however, first plus second services combined and overall conception rates were not affected (P >or= 0.23). In Exp. 2, NAT cows had greater (P = 0.002) concentrations of alpha-tocopherol at breeding, whereas there was no difference (P > 0.05) between SYN and CON. Supplementation of SYN or NAT did not affect (P >or= 0.17) days to resumption of estrus before breeding, first service, first plus second services combined, or overall conception rates. These data suggest that supplementation of SYN or NAT source vitamin E increased alpha-tocopherol concentration in cows; however, effects on reproductive efficiency are minimal.
Authors:
M Horn; P Gunn; M Van Emon; R Lemenager; J Burgess; N A Pyatt; S L Lake
Publication Detail:
Type:  Journal Article; Randomized Controlled Trial     Date:  2010-05-21
Journal Detail:
Title:  Journal of animal science     Volume:  88     ISSN:  1525-3163     ISO Abbreviation:  J. Anim. Sci.     Publication Date:  2010 Sep 
Date Detail:
Created Date:  2010-08-13     Completed Date:  2010-12-14     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8003002     Medline TA:  J Anim Sci     Country:  United States    
Other Details:
Languages:  eng     Pagination:  3121-7     Citation Subset:  IM    
Affiliation:
Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animal Feed
Animal Nutritional Physiological Phenomena
Animals
Cattle / physiology*
Diet / veterinary
Dietary Supplements
Female
Pregnancy
Reproduction / drug effects*
alpha-Tocopherol / administration & dosage,  chemistry*,  pharmacology*
Chemical
Reg. No./Substance:
59-02-9/alpha-Tocopherol

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


Previous Document:  Dietary effects of distillers dried grains with solubles on performance and milk composition of lact...
Next Document:  Effects of lactation feed intake and creep feeding on sow and piglet performance.