Some Factors Affecting the Rate of Pregnancy after Embryo Transfer Derived from the Brazilian Jumper Horse Breed

This study aimed to evaluate the effects of certain embryo transfer parameters on the pregnancy rate after equine embryo transfer of the Brazilian Jumper Horse breed. The size, embryonic development stage, embryo quality, and synchronization of ovulation between the donor (n = 120) and recipient (n = 420) were evaluated in 396 embryos. Embryo recovery was performed on Day 6-9 after ovulation (Day 0 = day of ovulation). The recipient mares were chosen on the day of embryo recovery, and the transfers were performed that same day. The embryo size (diameter including envelopes; n = 396) ranged from 150 to 3000 μm; 67.1% measured between 400 and 1199 μm. The embryo size (400-1199 μm vs. ≤399 μm); stage of development (n = 396; blastocyst and expanded blastocyst versus compact morula and early blastocyst); quality (n = 396; grade 1 [excellent]), 2 [good], or 3 [poor]); and synchronization of ovulation between the donor and recipient (0, 1, 2, 3, and 4 days versus −1, 5, and 6 days, respectively) all affected pregnancy rate (P < .05). The pregnancy rate did not differ significantly among transfers performed on Days 0, 1, 2, 3, and 4. In conclusion, embryos measuring 400-1199 μm produced higher pregnancy rates in recipients than embryos measuring 150-399 μm, and blastocysts and expanded blastocysts produced pregnancy more efficiently than morulae and early blastocysts. The embryo quality also affected the pregnancy rate. Synchronization of donor and recipient ovulation to Days 0-4 improved the efficiency of embryo transplant.     

Safety and efficacy of an oil-adjuvant vaccine against haemorrhagic septicaemia in buffalo calves: cross-protection between the serotypes B:2,5 and E:2,5.

The safety, efficacy and duration of immunity of an improved oil-adjuvant vaccine against haemorrhagic septicaemia, containing inactivated cells of Pasteurella multocida serotype B:2,5, were tested in young buffalo calves in Pakistan. For safety testing, five buffalo calves were vaccinated intramuscularly with twice the normal dose, and six weeks later with a normal dose. Except for a transient rise in rectal temperature at six hours after the vaccinations, no systemic reactions were observed. The buffaloes remained in good condition and had a normal appetite. No local reactions were observed at the injection site. For efficacy testing two trials were carried out. In the first, buffalo calves were vaccinated intramuscularly either with two doses two-and-a-half months apart, or with a single dose, or left unvaccinated. They were challenged subcutaneously with virulent P multocida after eight, 13 or 15 months. After challenge at eight months the four buffaloes given two doses and the buffalo given one dose were protected, whereas the control animal developed the typical signs of the disease. After the challenges at 13 and 15 months, the vaccinated animals were still protected whereas the control animals died. In the second trial, buffalo calves were vaccinated intramuscularly either with two doses two months apart, or with a single dose at two months or left unvaccinated. The buffaloes were challenged after eight or 14 months. After challenge at eight months the four control animals died, whereas three of the four buffaloes given a single dose were protected. After challenge at 14 months, the three control animals died, whereas four of the five buffaloes given two doses and both the buffaloes given a single dose were protected. To test for cross-protection against the heterologous serotypes E:2,5 and B:3,4, groups of mice were vaccinated once or left unvaccinated. Four weeks later, the vaccinated and control groups were challenged with a dilution series of the different challenge cultures. The vaccine appeared to induce protection against challenge with different strains of serotypes B:2,5 and E:2,5 but not against strains of serotype B:3,4.     

Virulence-associated trimeric autotransporters of Haemophilus parasuis are antigenic proteins expressed in vivo

Glässer’s disease is a re-emerging swine disease characterized by a severe septicaemia. Vaccination has been widely used to control the disease, although there is a lack of extended cross-protection. Trimeric autotransporters, a family of surface exposed proteins implicated in host-pathogen interactions, are good vaccine candidates. Members of this family have been described in Haemophilus parasuis and designated as virulence-associated trimeric autotransporters (VtaA). In this work, we produced 15 recombinant VtaA passenger domains and looked for the presence of antibodies directed against them in immune sera by immunoblotting. After infection with a subclinical dose of H. parasuis Nagasaki, an IgG mediated antibody response against 6 (VtaA1, 5, 6, 8, 9 and 10) of the 13 VtaA of the Nagasaki strain was detected, indicating that they are expressed in vivo. IgA production against VtaA was detected in only one animal. VtaA were more likely to be late antigens when compared to early (Omp P5 and Omp P6) and late (YaeT) defined antigens. Antibody cross-reaction with two orthologs of Nagasaki’s VtaA5 and 6, VtaA15 and 16 of strain HP1319, was also detected. No antibodies against VtaA were detected in the sera of animals immunized with a bacterin of the Nagasaki strain, suggesting poor expression in the in vitro conditions used. Taken together, these results indicate that VtaA are good candidate immunogens that could be used to improve H. parasuis vaccines. However, their capacity to confer protective immunity needs to be further studied.     

Excretion of BSE and scrapie prions in stools from murine models

Faeces from infected animals have been suggested as a potential source of contamination and transmission of prion diseases in the environment. This work describes the development of a procedure for the detection of PrP(res) in stools which is based on a detergent-based extraction and immunoprecipitation (IP). The procedure was evaluated by analyzing TSE-spiked sheep and mice faeces, and proved to be specific for PrP(res) with sensitivities of 5-10mug of infected brain tissue. In order to analyze the shedding of prions, we studied stools from orally inoculated mice over 4-days post-inoculation and also stools from terminally sick scrapie-infected mice. PrP(res) was only detected in stools shortly after the oral ingestion of TSE agents. The procedure described could be a useful tool for studying the excretion of prions and for evaluating potential environmental contamination by prions.     

Satellite teaching hospitals and public-private collaborations in veterinary medical clinical education

Veterinary teaching hospitals (VTHs) are facing more and greater challenges than at any time in the past. Changes in demand, expanding information, improving technology, an evolving workforce, declining state support, and an increasingly diverse consumer base have combined to render many traditional VTH modes of operation obsolete. In pursuit of continued success in achieving their academic mission, VTHs are exploring new business models, including innovative collaborations with the private sector. This report provides details on existing models for public-private collaboration at several colleges and schools of veterinary medicine, including those at Kansas State University, Purdue University, the University of Florida, and Tufts University. Although each of these institutions' models is unique, several commonalities exist, related to expansion of the case load available for teaching, the potential positive impact on recruitment and retention of clinical faculty, and the potential for easing financial pressures on the associated VTH. These new models represent innovative approaches that work to meet many of the key emerging challenges facing VTHs today.     

Risk of hemolytic anemia with intravenous administration of famotidine to hospitalized cats

BACKGROUND: Famotidine administered IV has been associated anecdotally with hemolysis in cats, and some veterinarians recommend using injectable famotidine only by the subcutaneous (SC) route for cats. However, the actual risk of such a reaction is not known. HYPOTHESIS: We hypothesized that famotidine, when given IV slowly, would not be associated with a clinically significant drop in packed cell volume (PCV) in hospitalized cats. ANIMALS: One hundred and forty-two hospitalized cats. METHODS: A retrospective medical record review was performed for hospitalized cats prescribed famotidine IV (n = 56), famotidine SC (n = 48), or no famotidine (n = 38) at a veterinary medical teaching hospital over the period from January 2004 through December 2006. RESULTS: Baseline signalment, observation times, and famotidine dosage (in treated cats) were similar among groups. Median baseline PCVs were significantly lower in the IV (31.5%) and SC (32.0%) groups compared with the control group (35.0%; P= .04). The median percent drop in PCV (3-4%), however, was no different in cats that received famotidine by either route compared with the control group (P= .90), and no cats in either famotidine group were observed to have any clinical signs of hemolysis. CONCLUSIONS AND CLINICAL IMPORTANCE: We conclude from this retrospective study that famotidine IV was given to 56 hospitalized cats without evidence of hemolysis, and that the IV route appeared safe when famotidine was administered over 5 minutes. We could not document a safety advantage of SC versus IV administration in this group of cats.     

Evaluation of Praziquantel effects on Echinostoma paraensei ultrastructure

Echinostomiasis is a food-borne, intestinal, zoonotic, snail-mediated helminthiasis caused by digenean trematodes of the family Echinostomatidae with seven species of the genus Echinostoma infecting humans or domestic and wildlife animals. Echinostoma paraensei is a peristomic 37-collar-spined echinostome belonging to the “revolutum group”.     

Beacon-like immunoreactivity in the hypothalamus of domestic chick

Beacon-immunoreactive (B-ir) fibres and neurons in the hypothalamus of the domestic chick (Gallus domesticus) were studied using an immunohistochemical technique in order to verify the presence and elucidate the pattern of distribution of this novel peptide in an avian brain. B-ir neurons were seen in the n. supraopticus, pars ventralis and pars externus; n. magnocellularis preopticus, pars dorsalis, medialis and ventralis; n. preopticus periventricularis; n. suprachiasmaticus, pars medialis; n. ventrolateralis thalami. Only few B-ir cells were scattered in the most anterior part of the lateral hypothalamic area. B-ir fibres, appearing as thin punctuate structures, were seen mainly along the walls of the third ventricle and in the ventromedial hypothalamus. Labelled fibres and terminals were located in the external and internal zones of the anterior and posterior median eminence. In particular, fibre terminals were seen close to the capillary loops of the hypothalamo-hypophysial portal system. The anatomical data of the present study regarding the distribution of B-ir in the chick hypothalamus suggest that beacon may play a key role in the regulation of the neuroendocrine system by acting as a neuromodulator and/or neurotransmitter.     

A survey of mutations in the Cochliomyia hominivorax (Diptera: Calliphoridae) esterase E3 gene associated with organophosphate resistance and the molecular identification of mutant alleles

Cochliomyia hominivorax (Calliphoridae) is one of the most important myiasis-causing flies and is responsible for severe economic losses to the livestock industry throughout the Neotropical region. In Brazil, C. hominivorax has been controlled mainly with organophosphate (OP) insecticides, although the inappropriate use of these chemicals can result in the selection of resistant flies. Changes in carboxylesterase activity have been associated with OP insecticides in some arthopodan species. In this work, we isolated and characterized part of the E3 gene in C. hominivorax (ChE7), which contained the same substitutions responsible for the acquisition of OP hydrolase activity in Lucilia cuprina (Calliphoridae). Digestion of the polymerase chain reaction products with a restriction enzyme that specifically recognized the mutation site unambiguously differentiated wild and mutated esterase alleles. The PCR-RFLP assay therefore provided a fast, reliable DNA-based method for identifying C. hominivorax individuals with a mutation in the esterase gene. Further bioassays to determine the association of this mutation with OP resistance in C. hominivorax should allow the development of more effective strategies for managing this species.