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Risk factors related to resistance to Rhipicephalus (Boophilus) microplus and weight gain of heifers
(2015-01-01)
The aim of the present study was to evaluate the influence of age and genetics in dairy heifers on resistance to the cattle tick Rhipicephalus (Boophilus) microplus and correlate these parameters with weight gain. Twenty-two ...
Evaluation of a modified GnRH-based timed-AI protocol associated with estrus detection in beef heifers inseminated with sex-selected or conventional semen
(Elsevier B.V., 2018-09-15)
The main objective was to compare pregnancy per Al (P/AI) between sex-selected and conventional semen in cyclic beef heifers subjected to a 5-day Co-synch plus CIDR protocol and evaluated the usefulness of an estrus detection ...
Genetic associations of sexual precocity with growth traits and visual scores of conformation, finishing, and muscling in Nelore cattle
(Amer Soc Animal Science, 2009-05-01)
The objective of this study was to determine the possible use of heifer pregnancy at 16 mo as a selection criterion and its possible genetic associations with hip height, yearling weight, and visual scores of conformation, ...
Peri-estrus ovarian, uterine, and hormonal variables determine the uterine luminal fluid metabolome in beef heifers
(2021-11-15)
In cattle, uterine luminal fluid (ULF) is the main source of molecules that support embryo development and survival during the peri-implantation period. Our overarching hypothesis is that peri-estrus changes in uterine ...
Effect of interval from induction of puberty to initiation of a timed AI protocol on pregnancy rate in Nellore heifers
(Elsevier B.V., 2014-09-15)
Prepubertal Bos indicus heifers (n = 774) were submitted to an E-2/P-4-based timed artificial insemination (TAI) protocol at three different intervals after induction of their pubertal ovulation by insertion of an intravaginal ...
Pre- and post-weaning injections of bovine somatotropin to optimize puberty achievement of Bos indicus beef heifers
(Oxford Univ Press Inc, 2019-01-01)
The present study evaluated the growth and puberty attainment of Bos indicus heifers administered recombinant bovine somatotropin (bST) or saline injections during preweaning and/or postweaning. On day 0, 177 suckling ...
Genetic associations between scrotal circumference and female reproductive traits in Nelore cattle
(Amer Soc Animal Science, 2015-06-01)
The objective of this study was to estimate genetic associations between scrotal circumference obtained at 12 (SC12; mean of 21.46 +/- 2.74 cm), 15 (SC15; mean of 25.31 +/- 3.19 cm), and 18 mo of age (SC18; mean of 26.77 ...
Genetic associations between scrotal circumference and female reproductive traits in nelore cattle
(2015-06-01)
The objective of this study was to estimate genetic associations between scrotal circumference obtained at 12 (SC12; mean of 21.46 ± 2.74 cm), 15 (SC15; mean of 25.31 ± 3.19 cm), and 18 mo of age (SC18; mean of 26.77 ± ...
Trisomy X and 1 29 translocation in infertile heifers
(1987-12-01)
In a group of 12 Pitangueiras breed heifers exhibiting a high return rate to service, three were noted to be carriers of the 1 29 translocation. One of the heifers exhibited trisomy for the X-chromosome in addition to the ...
Ovariectomy by left flank approach in prepubertal Nelore (Bos indicus) heifers
(Canadian Vet Med Assoc, 2009-07-01)
The main objective of this study was to evaluate a recumbent left flank approach to bilateral ovariectomy in prepubertal heifers and to develop an optimal surgical technique for this procedure. Both ovaries were removed ...