Document Detail


Body growth, growth hormone, prolactin and puberty response to photoperiod and plane of nutrition in Holstein heifers.
MedLine Citation:
PMID:  6643304     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Effects of photoperiod and plane of nutrition on growth, serum concentrations of prolactin (PRL) and growth hormone (GH) and puberty were assessed in Holstein heifers. Sixty pre-pubertal heifers were assigned to one of four treatment groups arranged in a 2 X 2 factorial. The two main effects were photoperiods of 8 h light: 16 h dark (8L:16D) vs 16L:8D, and a low vs high plane of nutrition. Heifers on the low plane of nutrition were fed a diet formulated to achieve a body growth rate of approximately .7 kg/d. Daily feed intake was restricted and similar in both groups of low plane heifers subjected to either 8 or 16 h of light daily. Heifers on the high plane of nutrition were fed ad libitum to achieve a growth rate greater than 1 kg/d. Body weight was recorded every month for 5 mo. The PRL and GH concentrations were measured at d 9, 53 and 132 in serum collected every 30 min for 6 h from five heifers in each treatment group. Progesterone was monitored biweekly in all heifers as an index of puberty (greater than 1 ng/ml). Heifers subjected to 8L:16D-low plane, 16L: 8D-low plane, 8L:16D-high plane or 16L:8D-high plane gained .61, .72, .98 and 1.08 kg/d, respectively. In the same treatment order, averaging across all bleedings, concentrations of PRL were 32, 37, 38 and 46 ng/ml serum, and GH averaged 10.9, 9.3, 9.8 and 9.0 ng/ml serum. Similarly, body weight at puberty averaged 268, 257, 278 and 268 kg, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
Authors:
D Petitclerc; L T Chapin; R S Emery; H A Tucker
Related Documents :
16829014 - Insulin-like growth factor type-1 receptor down-regulation associated with dwarfism in ...
8914494 - Sixteen weeks of hexarelin therapy in aged dogs: effects on the somatotropic axis, musc...
3791654 - Prolactin and stress: some endocrine correlates of pre-operative anxiety.
8412844 - Hormonal treatments modulate pulsatile plasma growth hormone, gonadotrophin and osteoca...
12198004 - Pharmacokinetics of the glucuronide and sulfate conjugates of genistein and daidzein in...
16135994 - Plasma orexin a, orexin b, leptin, neuropeptide y (npy) and insulin in obese women.
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  Journal of animal science     Volume:  57     ISSN:  0021-8812     ISO Abbreviation:  J. Anim. Sci.     Publication Date:  1983 Oct 
Date Detail:
Created Date:  1984-01-07     Completed Date:  1984-01-07     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8003002     Medline TA:  J Anim Sci     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  892-8     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Body Weight*
Cattle / physiology*
Diet*
Female
Growth Hormone / blood*
Lighting*
Prolactin / blood*
Seasons
Sexual Maturation*
Chemical
Reg. No./Substance:
9002-62-4/Prolactin; 9002-72-6/Growth Hormone

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


Previous Document:  Performance of selected and control lines of Duroc and Yorkshire pigs and their reciprocal crossbred...
Next Document:  Effect of dietary fat source and level on the performance of neonatal and early weaned pigs.