Recombinant bovine somatotropin in the synchronization of ovulation in crossbred dairy cows (Bos taurus indicus × Bos taurus taurus)

Biological Efficiency Differences Among Bos taurus x Bos taurus andBos indicus x Bos taurus F1-Cross Cows

Growth hormone mRNA expression in the pituitary of Bos indicus and Bos taurus x Bos indicus crossbred young bulls treated with recombinant bovine somatotropin.

The effects of breed and of recombinant bovine somatotropin (rbST) treatment on growth hormone gene expression were studied in young bulls. The experiment was completely randomized in a [2 x 2]-factorial arrangement, using two levels of rbST (0 or 250 mg/animal/14 days), and two breed groups (Nelore and Simmental x Nelore crossbred). A cDNA encoding Bos indicus growth hormone was cloned and seq...

Abnormal Bovine (Bos taurus L.) Karyotypes1

The addition of BUDR (5-bromodeoxiuridine), a thymine analogue, to cell cultures causes various chromosomic changes, depending on the length of treatment and when the BUDR is incorporated into the DNA molecule. A short BUDR treatment of cells in the second half of the S-phase causes symmetrical chromosome segmentation (Zacharov et al. 1971), while prolonged contact over two division cycles indu...

Endocrine and metabolic differences between Bos taurus and Bos indicus cows and implications for reproductive management

Based on the considerable differences in ovarian morphology and function, as well as circulating hormones and metabolites between Bos indicus (B. indicus) and Bos taurus (B. taurus), researchers are using this acquired knowledge to optimize protocols for fixed-time artificial insemination (FTAI), and production of in vivo derived embryos by multiple ovulation or by in vitro embryo production (I...

Pregnancy rate and birth rate of calves from a large-scale IVF program using reverse-sorted semen in Bos indicus, Bos indicus-taurus, and Bos taurus cattle.

Obtaining sexed sperm from previously frozen doses (reverse-sorted semen [RSS]) provides an important advantage because of the possibility of using the semen of bulls with desired genetic attributes that have died or have become infertile but from whom frozen semen is available. We report the efficiency of RSS on the pregnancy rate and birth rate of calves in a large-scale program using ovum pi...