Background: The respiratory pathogen Bordetella parapertussis is a valuable model in which to study the complex phenotype of host specificity because of its unique two-species host range. One subset of strains, including the sequenced representative, causes whooping cough in humans, while other strains infect only sheep. The disease process in sheep is not well understood, nor are the genetic a...

Background: Many hormones are involved in the regulation of reproduction. Leptin hormone which is mainly secreted by adipose tissue plays an important role in energy homeostasis and reproduction. It seems that leptin is an important linkage between body metabolism and reproductive system. Moreover, it has been shown that leptin and leptin receptor express in reproductive organs of some species....

BACKGROUND The United States control program for classical ovine scrapie is based in part on the finding that infection is typically spread through exposure to shed placentas from infected ewes. Transmission from goats to sheep is less well described. A suitable rodent model for examining the effect of caprine scrapie isolates in the ovine host will be useful in the ovine scrapie eradication ef...

The decline in pulsatile LH secretion and pituitary responsiveness to GnRH as pregnancy advances may be due to non-steroidal factors secreted by the ovine corpus luteum of pregnancy. Corpora lutea from ten ewes on days 70-80 of gestation were homogenized, charcoal-treated and, together with charcoal-treated follicular fluid from superovulated women, were subjected to inhibin immunoaffinity chro...

Genus and Species. Ovis aries. Locus. Ovine DNA segment OarTMR1 associated with ovine v-akt1 murine thymoma viral oncogene homolog 1 (AKT1) and ovine DNA segment OB2 associated with ovine bradykinin receptor B2 (BDKRB2). Source and Description of Primers. Primers for AKT1 (GenBank accession no. AF207873) were obtained from Scott Fahrenkrug, USDA-MARC, Clay Center, Nebraska, and were sent to Dan...

Natural killer (NK) cells represent an important component of the innate immune system. In ruminants there are few reports regarding presence or characterization of NK cells. Although absence of expression of major histocompatibility complex proteins on ovine trophoblast makes it potentially a target for NK cells, little is known about regulation of NK cells by products of pregnancy in sheep. O...

The analysis of the early macrophage responses, including bacterial growth within macrophages, represents a powerful tool to characterize the virulence of clinical isolates of Mycobcaterium avium susbp. paratuberculosis (Map). The present study represents the first assessment of the intracellular behaviour in ovine monocyte-derived macrophages (MDMs) of Map isolates representing distinct genoty...

Restriction endonuclease analysis and DNA hybridization revealed five ovine strains of Mycobacterium paratuberculosis from South Africa had identical DNA patterns to an ovine strain from Canada. Genetically this strain type has features in common with the two major groups of M. paratuberculosis.

studies on the pathogenesis of babesia ovis infection following blood transfusion of infected blood to sheep with intact spleen and splenectomised sheep showed that all animals developed fever concurrent with a parasitaemia that were occurred within 2-4 days post-inoculation (dpi), clinical signs of disease were severe and included varying degrees of anorexia, listlessness, anaemia, moderate ja...