This paper compares the effects of exposure to exogenous melatonin (MEL), short days (SD, 8h of light) and long days (LD, 16 h of light), on reproductive activity, sperm motility and other reproductive variables, in Blanca Andaluza bucks. Fourteen males were spilt into two groups of seven animals (G1 and G2). They were subjected to five alternations of 2 months of LD followed by 2 months of SD ...

Neosporosis is caused by the protozoan parasite, Neospora caninum which is major cause of fatal disease and abortion in cattle in Iran and in many countries. The economic impacts of neosporosis are lost milk, meat and abortions in cattle. The purpose of the present study was to evaluate the presence of N. caninum DNA in fresh and frozen semen samples of Iranian bulls that were used for artifici...

Studies were conducted using 68 males from the seventh generation of a line of meat-type breeder chickens selected for increased duration of fertility of frozen-thawed semen and 69 males of the randomly selected control line. These chickens were used to determine the presence or absence of differences between the selected and control lines with respect to fertility and spermatozoal motility whe...

The present study was designed to evaluate kinematic response of sperm cell to low-density lipoproteins (LDL) in fresh diluted, short-term (4°C) or long-term (-196°C) stored semen. Four healthy bucks of similar age and weight were selected as semen donor. The semen was collected twice a week using artificial vagina. The semen after initial evaluation was pooled and divided into three aliquots, ...

It is of critical importance to understand the modalities of BLV presence in semen, especially with regard to artificial insemination (AI). Presence of bovine leukemia provirus was demonstrated in fresh and frozen semen samples by researchers. In this study paired blood and semen samples from 45 bulls were assessed for the presence of part of gag gene and antibodies to BLV in blood, semen and c...

Artificial insemination via cooled or frozen-shipped semen allows more mares to be bred to a single stallion, but not all stallions produce semen capable of withstanding the cooling and freezing procedures. Aurich et al. (1996) estimated that cooled or frozen-shipped semen achieves < 75% of the pregnancy rates achieved with fresh semen. Some factors affecting the fertility rates of thawed semen...

the aim of the present study was to investigate the effect of in vitro supplementation of selenium on fresh and frozen spermatozoa quality of buffalo (bubalus bubalis) bulls. five healthy buffalo bulls (5 ejaculates from each bull) were used. each ejaculate was diluted at 37 ˚c with tris-based extender containing 0 (control), 0.5, 1, 2, 4 and 8 μg ml-1 sodium selenite and the sperm motility and...

BACKGROUND Assessment of sperm morphology (including morphometry) is extensively used to determine one of the qualities of a semen sample and depends on the differential staining of spermatozoa. A staining technique should cause as little change to sperm dimensions and form as possible in order to reliably evaluate the morphometric features of the sperm. Various staining techniques have been em...