A New Method of Assessing Sheep Red Blood Cell Types from Their Morphology.

Data concerning the morphometric parameters of sheep red blood cells (RBCs) obtained using computer-assisted image analysis have not yet been investigated, and there are no data on any analyses of ovine RBC subpopulations based on their morphometric parameters. The aims of this study are to determine the values of RBC haematological and morphometric size and shape parameters, to form groups according to the obtained values of haematological parameters; to determine the differences in RBC morphometric parameters between the formed groups, and to determine RBC subpopulations and their respective proportions in the formed groups. Thirty-six blood samples were collected from the jugular vein of clinically healthy Lika pramenka sheep, aged between 2 and 5 years.

The influence of exogenous melatonin on antioxidative status in seminal plasma and spermatozoa in French Alpine bucks during the nonbreeding season.

Research data regarding exogenous melatonin effects on buck semen antioxidative status during the breeding and nonbreeding seasons are scarce or missing. The aim of this study was to investigate the effect of melatonin implants on the activity and ratios of antioxidative enzymes and on malondialdehyde concentrations in the seminal plasma and spermatozoa of French Alpine bucks during the 3 mo of the nonbreeding season. Two groups of randomly assigned bucks were either treated with melatonin (n = 6) or served as controls (n = 6).

Exogenous melatonin influences distribution of French Alpine buck spermatozoa in morphometrically distinct subpopulations during the non-breeding season.

The aim of this study was to establish subpopulations of spermatozoa in bucks using the principal component (PC) and cluster analysis according to morphometric head and tail variables, and to determine differences in proportions of subpopulations between exogenous melatonin-treated and control bucks. The bucks (n = 12) were assigned to two groups comprising six bucks each. By the end of March, four melatonin implants were inserted in the bucks in the experimental group.

Age-related differences of semen quality, seminal plasma, and spermatozoa antioxidative and oxidative stress variables in bulls during cold and warm periods of the year.

The aims of this study were to determine the presence and quantities of antioxidative status and oxidative stress (OS) variables in the seminal plasma and spermatozoa of bulls of varying age during cold and warm periods of the year, and to establish the correlation of these variables with semen quality parameters. The study was conducted on two groups each comprising nine Simmental bulls: one group contained younger animals (aged 2 to 4 years) and the second older animals (aged 5 to 10 years). Semen samples were collected using an artificial vagina for biochemical analysis.

Monitoring of libido and semen quality parameters in melatonin-treated French alpine bucks during the non-breeding season.

The aim of this study was to investigate the effects of exogenous melatonin on libido and semen quality parameters in bucks during the non-breeding season. Twelve bucks of the French alpine breed from 1.5 to 4 years of age were assigned into melatonin (MG) and control (CG) groups, with 6 bucks in each group.