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First lactation ovarian function in dairy heifers in relation to prepubertal metabolic profiles.
J Endocrinol 2004; 180(1):63-75JE

Abstract

The aim of this study was to determine whether any differences in the GH-IGF-I axis in juvenile calves were predictive of fertility problems as adult cows. Endogenous metabolic hormone profiles before and after feeding and the response to a GH-releasing factor (GRF) challenge were measured in prepubertal (6 month) dairy calves. These metabolic parameters were subsequently related to physical characteristics at puberty and to ovarian function during the first lactation. Milk progesterone analysis was used to categorize the animals into those with normal progesterone profiles following calving (n=17) and those that developed delayed ovulation (DOV1, n=9) or persistent corpus luteum (PCL1, n=6) profiles. There were associations between prepubertal GH parameters, glucose and non-esterified fatty acid (NEFA) concentrations and the body condition score at which the animals attained puberty. The calves which subsequently developed DOV1 profiles as cows tended to have a higher GH pulse amplitude during fasting than normal profile animals, they did not show the anticipated decrease in circulating glucose concentrations following a post-prandial rise in insulin and they also had the lowest IGF-I concentrations. The calves that later developed PCL1 had a significantly larger GH pulse amplitude and pulse area than normal profile animals in the fed period and had the highest IGF-I concentrations. There were no differences in prepubertal insulin or NEFA concentrations or in the GH response to a GRF challenge between the different progesterone profile categories. Plasma IGF-I concentrations in prepubertal animals were positively correlated with their post-calving concentrations, whereas glucose concentrations had a negative correlation between these time-periods. These results suggested that the different juvenile endocrine profiles of the DOV1 cows may predispose them to a higher rate of tIssue mobilization during lactation and a consequent reduction in fertility, while altered GH and IGF-I levels in PCL1 cows may later contribute to the maintenance of the persistent corpus luteum. Therefore metabolic differences in prepubertal calves were later reflected by altered reproductive function during the first lactation.

Authors+Show Affiliations

Department of Veterinary Basic Sciences, Royal Veterinary College, University of London, Hatfield AL9 7TA, UK.No affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

14709145

Citation

Taylor, V J., et al. "First Lactation Ovarian Function in Dairy Heifers in Relation to Prepubertal Metabolic Profiles." The Journal of Endocrinology, vol. 180, no. 1, 2004, pp. 63-75.
Taylor VJ, Beever DE, Bryant MJ, et al. First lactation ovarian function in dairy heifers in relation to prepubertal metabolic profiles. J Endocrinol. 2004;180(1):63-75.
Taylor, V. J., Beever, D. E., Bryant, M. J., & Wathes, D. C. (2004). First lactation ovarian function in dairy heifers in relation to prepubertal metabolic profiles. The Journal of Endocrinology, 180(1), pp. 63-75.
Taylor VJ, et al. First Lactation Ovarian Function in Dairy Heifers in Relation to Prepubertal Metabolic Profiles. J Endocrinol. 2004;180(1):63-75. PubMed PMID: 14709145.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - First lactation ovarian function in dairy heifers in relation to prepubertal metabolic profiles. AU - Taylor,V J, AU - Beever,D E, AU - Bryant,M J, AU - Wathes,D C, PY - 2004/1/8/pubmed PY - 2004/3/11/medline PY - 2004/1/8/entrez SP - 63 EP - 75 JF - The Journal of endocrinology JO - J. Endocrinol. VL - 180 IS - 1 N2 - The aim of this study was to determine whether any differences in the GH-IGF-I axis in juvenile calves were predictive of fertility problems as adult cows. Endogenous metabolic hormone profiles before and after feeding and the response to a GH-releasing factor (GRF) challenge were measured in prepubertal (6 month) dairy calves. These metabolic parameters were subsequently related to physical characteristics at puberty and to ovarian function during the first lactation. Milk progesterone analysis was used to categorize the animals into those with normal progesterone profiles following calving (n=17) and those that developed delayed ovulation (DOV1, n=9) or persistent corpus luteum (PCL1, n=6) profiles. There were associations between prepubertal GH parameters, glucose and non-esterified fatty acid (NEFA) concentrations and the body condition score at which the animals attained puberty. The calves which subsequently developed DOV1 profiles as cows tended to have a higher GH pulse amplitude during fasting than normal profile animals, they did not show the anticipated decrease in circulating glucose concentrations following a post-prandial rise in insulin and they also had the lowest IGF-I concentrations. The calves that later developed PCL1 had a significantly larger GH pulse amplitude and pulse area than normal profile animals in the fed period and had the highest IGF-I concentrations. There were no differences in prepubertal insulin or NEFA concentrations or in the GH response to a GRF challenge between the different progesterone profile categories. Plasma IGF-I concentrations in prepubertal animals were positively correlated with their post-calving concentrations, whereas glucose concentrations had a negative correlation between these time-periods. These results suggested that the different juvenile endocrine profiles of the DOV1 cows may predispose them to a higher rate of tIssue mobilization during lactation and a consequent reduction in fertility, while altered GH and IGF-I levels in PCL1 cows may later contribute to the maintenance of the persistent corpus luteum. Therefore metabolic differences in prepubertal calves were later reflected by altered reproductive function during the first lactation. SN - 0022-0795 UR - https://www.unboundmedicine.com/medline/citation/14709145/First_lactation_ovarian_function_in_dairy_heifers_in_relation_to_prepubertal_metabolic_profiles_ L2 - https://joe.bioscientifica.com/doi/10.1677/joe.0.1800063 DB - PRIME DP - Unbound Medicine ER -