This study evaluated the impact of coat color (CC) and hair coat characteristics (HC) on productive and physiological traits related to thermotolerance in Angus heifers. The goal was to determine if HC and/or CC were reliable indicators of thermotolerance on a large scale for future breeding programs. Ninety-three 15-month-old Angus heifers (52 black, 41 red) were evaluated in three periods on a beef cattle farm in Brazil.
View Article and Find Full Text PDFThe study investigated midpiece defects in sperm from a 5-year-old Brangus bull with a high rate of semen batch rejection, due to morphologically abnormal sperm, with no reduction in sperm kinematics. A comprehensive evaluation was conducted over a 16-month period, involving 28 ejaculates. Notably, despite the high proportion of midpiece defects (average 37.
View Article and Find Full Text PDFTo date, there have been no studies testing the capacity of GnRH analogs and respective doses to induce a LH peak in sheep. In this sense, the present study aimed to evaluate the capacity of different synthetic forms and doses of GnRH in inducing LH release in sheep, and the effect of GnRH administration at timed artificial insemination (TAI) on pregnancy per timed-AI. In experiment 1, ewes (n = 40) received an intravaginal device (IVD) of medroxyprogesterone acetate (MPA; 60 mg) for 7 d and prostaglandin F analog on Day 5.
View Article and Find Full Text PDFEstradiol cypionate (EC) or GnRH have been widely used for ovulation induction in timed embryo transfer (TET). EC administration increases the proportion of cows that show estrus, whereas GnRH promotes more synchronized ovulations. The aim of the present study was to evaluate the potential beneficial effects of combining EC and GnRH in TET.
View Article and Find Full Text PDFAbstract: The traffic in international animal products can become a public health hazard when legal import sanitary procedures are not followed. In Brazil, due to its extensive border area, the importation of animal products is a common practice in many areas, especially in Rio Grande do Sul, a state that borders Argentina and Uruguay. The objective of this study was to evaluate the presence of veterinary drug residues (antibiotics and antiparasitics) in animal products consumed in Rio Grande do Sul.
View Article and Find Full Text PDFOocyte-derived bone morphogenetic protein 15 (BMP15) is one of the main local regulators of ovarian physiology, but its role in the regulation of preovulatory follicles and ovulation is not well established. Therefore, this study was conceived to determine the effect of intrafollicular injection (IFI) of BMP15 on final follicular growth, ovulation and luteinization in cattle. Initially, it was observed that relative mRNA abundance of the BMP15 receptor BMPR1B in granulosa cells was regulated by GnRH treatment, and it was negatively correlated (R = 0.
View Article and Find Full Text PDFThe high lipid content in porcine oocytes impairs in vitro embryo production (IVP). Here, we evaluated the influence of two different lipid modulators during in vitro maturation (IVM) on the embryo development and the lipid content of oocytes and embryos. In Experiment I, oocytes were exposed to 50 μM docosahexaenoic acid (DHA) with (+) or without (-) the presence of porcine follicular fluid (pFF).
View Article and Find Full Text PDFThe aim of this study was to evaluate the effect of growth hormone (GH) deficiency in primordial follicle reserve, DNA damage and macrophage infiltration in the ovaries of young mice. Ovaries from six-month-old GH-deficient Ames Dwarf (df/df) and Normal (N/df) mice were used. The number of primordial follicles was higher in df/df mice (p = 0.
View Article and Find Full Text PDFThe aim of this study was to evaluate the effect of exposing bovine oocytes to lipopolysaccharides (LPS) in vivo and in vitro on early embryo development. In experiment 1, cumulus oocyte complexes (COCs, n = 700/group) were challenged with 0, 0.1, 1.
View Article and Find Full Text PDFBull Semen Collection and Processing Centers (SCPC) have satisfactory control of sperm quality, but commonly lack standardized quality control of hygiene procedures. This study assessed the impact of implementing a Hazard Analysis and Critical Control Points (HACCP) system in a bull SCPC, comparing microbial counts on various steps of semen processing, semen quality and costs across two periods (before and after the HACCP implementation). After surveying all routine activities of the SCPC, control points were identified, preventive measures were designed and corrective actions were employed, whenever necessary.
View Article and Find Full Text PDFIntense manipulation during beef jerky production increases the possibility of contamination with pathogenic microorganisms. This study evaluated the contamination by thermotolerant coliforms, Escherichia coli and Salmonella spp., on processing surfaces and raw materials during beef jerky production, as well as in the final product.
View Article and Find Full Text PDFBackground: The insulin receptor substrate 1 (IRS1), phosphoinositide 3-kinase (Pi3k), protein kinase B (Akt1), Forkhead Box O3a (FOXO3a) pathway is directly involved in aging and ovarian activation of follicle growth. Therefore, the aim of this work was to measure the expression of genes related to the ovarian pathway for activation of primordial follicles and FOXO3a protein phosphorylation between young and old female Ames dwarf (df/df) and normal (N) mice.
Methods: For this study ovaries from N (n = 10) and df/df (n = 10) female mice were collected at 5-6 months of age and at 21-22 months of age.
The objective of the present study was to describe ultrastructural changes in the nucleus and cytoplasmic organelles during in vitro maturation (IVM) of buffalo cumulus-oocyte complexes (COCs). The structures were collected by ovum pick-up (OPU). Some COCs, removed from maturation medium at 0, 6, 12, 18 and 24 h, were processed for transmission electron microscopy.
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