Results 211 to 220 of about 336,156 (254)

Factors affecting puberty in replacement beef heifers

Theriogenology, 2016
Puberty is defined as when ovulation is accompanied by visual signs of estrus and subsequent normal luteal function. Age at puberty is an important trait in relation to reproductive success, productive life span, and profitability in beef operations. Although puberty and initiation of normal estrous cycles are complex events that require maturation of ...
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Energy metabolism in lactating beef heifers.

Journal of Animal Science, 2000
To obtain measurements of energy balance in lactating beef cows, respiration calorimetry and digestion trials were conducted using seven lactating (613 kg BW) and three nonlactating (598 kg BW) Hereford x Angus heifers fed a pelleted 75% alfalfa:25% concentrate diet.
C K, Reynolds, H F, Tyrrell
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Photoperiod effects on the development of beef heifers

Canadian Journal of Animal Science, 2003
Crossbred beef heifers (n = 144) were assigned at weaning (187 ± 14 d of age) by body weight (225 ± 23 kg) and sire breed (British/Continental) to one of two photoperiod treatments from 21 Decem ber 1998 (0 wk) until 10 May 1999 (20 wk): natural photoperiod (NP) that gradually increased from 8.1 h (0 wk) to 15.2 h (20 wk) and, extended photoperiod (EP)
J. A. Small, N. D. Glover, A. D. Kennedy, W. P. McCaughey, D. R. Ward   +4 more
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Nonpuberal estrus in beef heifers.

Journal of animal science, 1986
The frequency of occurrence of behavioral estrus without subsequent development of functional luteal tissue (termed nonpuberal estrus, NPE), was determined in 43 Simmental X Hereford-Brahman heifers. Blood samples were collected weekly from the start of the study to first behavioral estrus and then daily from d 1 (d 0 = estrus) through d 14 following ...
L M, Rutter, R D, Randel
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Beef heifer estrus synchronization programs

The Bovine Practitioner, 1988
Oestrus synchronization by administration of PG, norgestomet + oestradiol valerate or MGA + PG is discussed.
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Synchronization of estrus after treatment with Luprostiol in beef cows and in beef and dairy heifers

Theriogenology, 1990
Four trials were conducted to study synchronous estrous response in beef cows and in beef and dairy heifers to Luprostiol (13, thia-PG-F(2)alpha analog) in comparison with other prostaglandin products. In Trial 1, 60 virgin beef heifers were observed for estrus for 5 d and artificially inseminated.
N I, Plata, J C, Spitzer, C E, Thompson, D M, Henricks, M P, Reid, T J, Newby   +5 more
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Resynchronization of previously timed-inseminated beef heifers with progestins

Theriogenology, 2006
The objective was to determine the efficacy of a previously used CIDR or melengestrol acetate (MGA; 0.5mg/head/day) for resynchronization of estrus in beef heifers not pregnant to timed-AI (TAI). In three experiments and a field trial, heifers were reinseminated 6-12 h after first detection of estrus.
M G, Colazo, J P, Kastelic, R C, Mainar-Jaime, Q A, Gavaga, P R, Whittaker, J A, Small, M F, Martinez, R E, Wilde, D M, Veira, R J, Mapletoft   +9 more
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Effect of embryo quality and developmental stages on pregnancy rate during fresh embryo transfer in beef heifers

Tropical Animal Health and Production, 2020
H. Erdem, T. Karaşahin, H. Alkan, Ş. Dursun, Fatma Satılmış, Mehmet Güler   +5 more
semanticscholar   +1 more source

Beef Heifer Record

2015
Reprint
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A note on the early calving of beef heifers

2016
No Abstract.
Scholtz, MM, Lombard, PE, Enslin, CB
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