The effects of accelerated growth rates and estrogen implants in prepubertal Holstein heifers on estimates of mammary development and subsequent reproduction and milk production

B. P. Lammers, Arlyn Judson Heinrichs, R. S. Kensinger

Research output: Contribution to journalArticle

53 Citations (Scopus)

Abstract

The objectives of this study were to determine the effects of accelerating growth rates and of imposing estrogen implants in prepubertal heifers on mammary development and subsequent reproduction and milk production. Sixty-eight Holstein heifers were assigned to 1 of 4 treatment groups by using a randomized complete block design in a 2 × 2 factorial arrangement. The treatments were standard growth rate (700 g/d) or accelerated growth rate (1000 g/d) and estrogen implant or no estrogen implant. The treatments were imposed over 20 wk, beginning at 4.5 mo of age and 130 kg of body weight (BW). During the treatment period, all heifers were fed individually and received the same diet, but the dry matter intake of each heifer was adjusted weekly to achieve the designated growth rate. The estrogen implants were removed at the end of the treatment period at 9.5 mo of age. After the treatment period, the heifers were group fed according to BW and age to allow the heifers to have a similar BW and age at calving. The accelerated growth regimen decreased age at puberty by 32 d. Age, BW, and body condition scores at calving were not significantly different among treatments. The accelerated prepubertal growth regimen decreased first lactation fat-corrected milk yield 7.1%. Prepubertal heifers given estrogen implants produced 5.2% less fat-corrected milk during first lactation than did heifers not implanted with estrogen. Estrogen implants stimulated a large increase in teat length growth during the treatment period, but the advantage was lost posttreatment. Over both the treatment and posttreatment periods, the estrogen implants reduced teat length growth by 30%. Accelerated growth rates from 700 to 1000 g/d and estrogen implants in prepubertal heifers decreased first lactation milk production.

Original languageEnglish (US)
Pages (from-to)1753-1764
Number of pages12
JournalJournal of dairy science
Volume82
Issue number8
DOIs
StatePublished - Jan 1 1999

Fingerprint

mammary development
estrogens
Reproduction
heifers
milk production
Estrogens
Milk
Breast
Holstein
Growth
Body Weight
Lactation
body weight
lactation
teats
calving
Fats
milk fat yield
puberty
Puberty

All Science Journal Classification (ASJC) codes

  • Food Science
  • Animal Science and Zoology
  • Genetics

Cite this

@article{9e4faf1160b64fbe931dcb8fdc9ed2b3,
title = "The effects of accelerated growth rates and estrogen implants in prepubertal Holstein heifers on estimates of mammary development and subsequent reproduction and milk production",
abstract = "The objectives of this study were to determine the effects of accelerating growth rates and of imposing estrogen implants in prepubertal heifers on mammary development and subsequent reproduction and milk production. Sixty-eight Holstein heifers were assigned to 1 of 4 treatment groups by using a randomized complete block design in a 2 × 2 factorial arrangement. The treatments were standard growth rate (700 g/d) or accelerated growth rate (1000 g/d) and estrogen implant or no estrogen implant. The treatments were imposed over 20 wk, beginning at 4.5 mo of age and 130 kg of body weight (BW). During the treatment period, all heifers were fed individually and received the same diet, but the dry matter intake of each heifer was adjusted weekly to achieve the designated growth rate. The estrogen implants were removed at the end of the treatment period at 9.5 mo of age. After the treatment period, the heifers were group fed according to BW and age to allow the heifers to have a similar BW and age at calving. The accelerated growth regimen decreased age at puberty by 32 d. Age, BW, and body condition scores at calving were not significantly different among treatments. The accelerated prepubertal growth regimen decreased first lactation fat-corrected milk yield 7.1{\%}. Prepubertal heifers given estrogen implants produced 5.2{\%} less fat-corrected milk during first lactation than did heifers not implanted with estrogen. Estrogen implants stimulated a large increase in teat length growth during the treatment period, but the advantage was lost posttreatment. Over both the treatment and posttreatment periods, the estrogen implants reduced teat length growth by 30{\%}. Accelerated growth rates from 700 to 1000 g/d and estrogen implants in prepubertal heifers decreased first lactation milk production.",
author = "Lammers, {B. P.} and Heinrichs, {Arlyn Judson} and Kensinger, {R. S.}",
year = "1999",
month = "1",
day = "1",
doi = "10.3168/jds.S0022-0302(99)75406-8",
language = "English (US)",
volume = "82",
pages = "1753--1764",
journal = "Journal of Dairy Science",
issn = "0022-0302",
publisher = "Elsevier Limited",
number = "8",

}

TY - JOUR

T1 - The effects of accelerated growth rates and estrogen implants in prepubertal Holstein heifers on estimates of mammary development and subsequent reproduction and milk production

AU - Lammers, B. P.

AU - Heinrichs, Arlyn Judson

AU - Kensinger, R. S.

PY - 1999/1/1

Y1 - 1999/1/1

N2 - The objectives of this study were to determine the effects of accelerating growth rates and of imposing estrogen implants in prepubertal heifers on mammary development and subsequent reproduction and milk production. Sixty-eight Holstein heifers were assigned to 1 of 4 treatment groups by using a randomized complete block design in a 2 × 2 factorial arrangement. The treatments were standard growth rate (700 g/d) or accelerated growth rate (1000 g/d) and estrogen implant or no estrogen implant. The treatments were imposed over 20 wk, beginning at 4.5 mo of age and 130 kg of body weight (BW). During the treatment period, all heifers were fed individually and received the same diet, but the dry matter intake of each heifer was adjusted weekly to achieve the designated growth rate. The estrogen implants were removed at the end of the treatment period at 9.5 mo of age. After the treatment period, the heifers were group fed according to BW and age to allow the heifers to have a similar BW and age at calving. The accelerated growth regimen decreased age at puberty by 32 d. Age, BW, and body condition scores at calving were not significantly different among treatments. The accelerated prepubertal growth regimen decreased first lactation fat-corrected milk yield 7.1%. Prepubertal heifers given estrogen implants produced 5.2% less fat-corrected milk during first lactation than did heifers not implanted with estrogen. Estrogen implants stimulated a large increase in teat length growth during the treatment period, but the advantage was lost posttreatment. Over both the treatment and posttreatment periods, the estrogen implants reduced teat length growth by 30%. Accelerated growth rates from 700 to 1000 g/d and estrogen implants in prepubertal heifers decreased first lactation milk production.

AB - The objectives of this study were to determine the effects of accelerating growth rates and of imposing estrogen implants in prepubertal heifers on mammary development and subsequent reproduction and milk production. Sixty-eight Holstein heifers were assigned to 1 of 4 treatment groups by using a randomized complete block design in a 2 × 2 factorial arrangement. The treatments were standard growth rate (700 g/d) or accelerated growth rate (1000 g/d) and estrogen implant or no estrogen implant. The treatments were imposed over 20 wk, beginning at 4.5 mo of age and 130 kg of body weight (BW). During the treatment period, all heifers were fed individually and received the same diet, but the dry matter intake of each heifer was adjusted weekly to achieve the designated growth rate. The estrogen implants were removed at the end of the treatment period at 9.5 mo of age. After the treatment period, the heifers were group fed according to BW and age to allow the heifers to have a similar BW and age at calving. The accelerated growth regimen decreased age at puberty by 32 d. Age, BW, and body condition scores at calving were not significantly different among treatments. The accelerated prepubertal growth regimen decreased first lactation fat-corrected milk yield 7.1%. Prepubertal heifers given estrogen implants produced 5.2% less fat-corrected milk during first lactation than did heifers not implanted with estrogen. Estrogen implants stimulated a large increase in teat length growth during the treatment period, but the advantage was lost posttreatment. Over both the treatment and posttreatment periods, the estrogen implants reduced teat length growth by 30%. Accelerated growth rates from 700 to 1000 g/d and estrogen implants in prepubertal heifers decreased first lactation milk production.

UR - http://www.scopus.com/inward/record.url?scp=0033174367&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033174367&partnerID=8YFLogxK

U2 - 10.3168/jds.S0022-0302(99)75406-8

DO - 10.3168/jds.S0022-0302(99)75406-8

M3 - Article

C2 - 10480102

AN - SCOPUS:0033174367

VL - 82

SP - 1753

EP - 1764

JO - Journal of Dairy Science

JF - Journal of Dairy Science

SN - 0022-0302

IS - 8

ER -