Advanced search
Start date
Betweenand
Related content
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Effects of bovine somatotropin injection on serum concentrations of progesterone in non-lactating dairy cows

Full text
Author(s):
Aboin, A. C. [1] ; Cooke, R. F. [2] ; Vieira, F. V. R. [1] ; Leiva, T. [1] ; Vasconcelos, J. L. M. [1]
Total Authors: 5
Affiliation:
[1] Fac Med Vet & Zootecnia UNESP, Dept Prod Anim, BR-18618000 Botucatu, SP - Brazil
[2] Oregon State Univ, Eastern Oregon Agr Res Ctr, Burns, OR - USA
Total Affiliations: 2
Document type: Journal article
Source: LIVESTOCK SCIENCE; v. 154, n. 1-3, p. 240-245, JUN 2013.
Web of Science Citations: 4
Abstract

The objective of this experiment was to evaluate the effects of bovine somatotropin administration on serum concentrations of glucose, insulin, NEFA, IGF-I, and progesterone (P4) in ovariectomized non-lactating dairy cows receiving exogenous P4, as a model to estimate treatment effects on hepatic P4 degradation. Ten non-lactating, non-pregnant, and ovariectomized Gir x Holstein cows were assigned to the experiment (d -14 to 27). On d 0, cows were ranked by BW and BCS, and randomly assigned to one of two treatments: (1) bovine somatotropin (BST; n=5) or (2) saline control (control; n=5). Cows assigned to the BST treatment were administered s.c. injections containing 500 mg of sometribove zinc on d 0, 9, and 18 of the experiment, whereas control cows concurrently received a 10-mL s.c. injection of 0.9% saline. On d -2, cows were inserted with an intravaginal releasing device containing 1.9 g of P4, which remained in the cows until the end the experiment (d 27). Cow BW and BCS were assessed on d -14, 0, and 27. Blood samples were collected daily from d 0 to d 27, at 0 (immediately before), I, and 2 h relative to concentrate feeding for determination of serum glucose, insulin, NEFA, P4, and IGF-I concentrations. Concentrations of glucose, NEFA, and insulin obtained prior to feeding (0 h) were used to determine pre-prandial revised quantitative insulin sensitivity check index (RQUICKI). No treatment effects were detected for BW (P=0.72) and BCS change (P=0.79) during the experiment. Beginning on d 2 of the experiment, BST cows had greater (P <= 0.01) serum IGF-I concentrations compared with control cohorts (treatment x day interaction; P<0.01). Cows receiving BST had greater (P <= 0.05) insulin concentrations compared with control cohorts from d 8 to d 11, d 16 and 17, as well as from d 19 to d 21 of the experiment (treatment x day interaction; P < 0.01). Cows receiving BST had greater (P <= 0.01) mean glucose and NEFA concentrations, as well as reduced (P < 0.01) mean RQUICKI during the experiment compared with control cohorts. No treatment effects, however, were detected (P=0.73) for serum P4 concentrations. In conclusion, results from this experiment indicate that hepatic P4 catabolism is not directly regulated by circulating IGF-I, whereas BST administration decreases insulin sensitivity in non-lactating dairy cows in adequate nutritional status. (C) 2013 Elsevier B.V. All rights reserved. (AU)

FAPESP's process: 11/10308-7 - Effects of bST injection on serum concentrations of glucose, insulin, IGF-1 and progesterone in nonlactating dry cows in different energy balance
Grantee:José Luiz Moraes Vasconcelos
Support Opportunities: Regular Research Grants