To develop a live vaccine strain against fowl typhoid and paratyphoid caused by Salmonella serovar Gallinarum biovar Gallinarum (Salmonella Gallinarum) and Salmonella serovar Enteritidis (Salmonella Enteritidis), respectively, several nalidixic acid resistant mutants were selected from lipopolysaccharide (LPS) rough strains of Salmonella Gallinarum that escaped from fatal infection of a LPS - binding lytic bacteriophage. A non - virulent and immunogenic vaccine strain of Salmonella Gallinarum, SR2 - N6, was established through in vivo pathogenicity and protection efficacy tests. SR2 - N6 was highly protective against Salmonella Gallinarum and Salmonella Enteritidis and safer than Salmonella Gallinarum vaccine strain SG 9R in the condition of protein-energy malnutrition. Thus, SR2 - N6 may be a safe and efficacious vaccine strain to prevent both fowl typhoid and paratyphoid.

Exercise is one of the most common stressors in horses. Although various physiological parameters such as cortisol respond to exercise, there is no reliable parameter for the measurement of exercise-induced stress in sport horses. This study was performed to discover a new biomarker with high sensitivity for exercise-induced stress. The expression of fos mRNA was increased more than 10-fold in horse blood samples collected after an hour of exercise, as compared with before the exercise. The plasma cortisol levels were also increased after the exercise, but only by about two-fold. The fos mRNA levels were well-correlated with plasma cortisol concentrations. These findings suggest that fos mRNA expression in blood may be useful for the measurement of exercise-induced stress in horses.

OBJECTIVE To determine the tonicity effects of β-hydroxybutyrate, acetoacetate, and lactate in canine RBCs. SAMPLE RBCs from approximately 40 dogs. PROCEDURES 2 in vitro methods were used to conduct 4 experiments. The modified osmotic fragility assay was used to measure the ability of ketoacid salts added to serial sucrose dilutions to protect RBCs from osmotic hemolysis. In a second assay, a handheld cell counting device was used to measure changes in RBC diameter to assess the tonicity effect of solutions of ketoacid and lactate salts. RESULTS For the modified osmotic fragility assay, all ketoacid salts had an osmoprotective effect, but the effect was determined to be completely attributable to the tonicity effect of added cations (sodium and lithium) and not the ketoacid moieties. However, both the sodium and lithium lactate salts provided osmoprotection attributable to both the cation and lactate anion. For the second assay, RBC diameter was significantly increased with the addition of urea (an ineffective osmole) but did not change with the addition of glucose (an effective osmole), which established the behaviors of ineffective and effective osmoles in this assay. The RBC diameter was significantly increased over that of control samples by the addition of sodium β-hydroxybutyrate, lithium acetoacetate, and lithium lactate but was decreased by the addition of sodium lactate. CONCLUSIONS AND CLINICAL RELEVANCE For both assays, β-hydroxybutyrate and acetoacetate acted as ineffective osmoles, whereas lactate acted as an effective osmole in 3 of 4 experiments.

The aim of the present study was morphological and histochemical analysis of the lacrimal gland (LG) in African black ostrich Struthio camelus domesticus in the embryonic and postnatal period. Studies were conducted on 50 ostriches aged between the 28th day of incubation until 7 months old. Tissue sections were stained with haematoxylin and eosin, Azan trichrome, periodic acid-Schiff, Alcian blue pH 2.5, aldehyde fuchsin and Hale's dialysed iron. The LG in ostrich was classified as a tubulo-acinar type. The primordia of the lobes were determined in the LG structure on the 28th day of incubation, whilst the weakly visible lobes with acini and tubules were observed on the 40th day of incubation. Morphometric studies of the LG showed steady growth, characterised by an increase in both length and width. Histometric measurements of lobe size showed little difference between the first, second and third age groups, whilst in the fourth age group a marked increase in size of lobes was observed. The study showed that, apart from morphological changes, during the growth of the LG the character of acid mucopolysaccharides changed. Sulphated acid mucopolysaccharides were indicated, particularly with aldehyde fuchsin (AF) staining in the fourth age group. The Hale's dialysed iron (HDI) staining showed a low concentration of carboxylated acid mucopolysaccharides in the first and second age groups and a higher concentration in the third and fourth age groups. Periodic acid-Schiff staining (PAS)-positive cells were observed in each age group, but only a small number of cells with a weakly PAS-positive reaction were demonstrated in the first age group.

Colibacillosis, a disease caused by avian pathogenic Escherichia coli (APEC), is one of the main causes of economic losses in the poultry industry worldwide. This study was carried out in order to determine the APEC-associated virulence genes contained by E. coli isolates causing colibacillosis in chickens. A total of 45 E. coli isolates were obtained from the diagnostics and research branch of the Central Veterinary Laboratories, Bulawayo, Zimbabwe. These isolates were obtained from chickens with confirmed cases of colibacillosis after postmortem examination. The presence of the iutA, hlyF, ompT, frz, sitD, fimH, kpsM, sitA, sopB, uvrY, pstB and vat genes were investigated by multiplex polymerase chain reaction (PCR) assay. Of the 45 isolates, 93% were positive for the presence of at least one virulence gene. The three most prevalent virulence genes were iutA (80%), fimH (33.3%) and hlyF (24.4%). The kpsM, pstB and ompT genes had the lowest prevalence, having been detected in only 2.2% of the isolates. All 12 virulence genes studied were detected in the 45 APEC isolates. Virulence gene profiles were constructed for each APEC isolate from the multiplex data. The APEC isolates were profiled as 62.2% fitting profile A, 31.1% profile B and 6.7% profile C. None of the isolates had more than seven virulence genes. Virulence profiles of Zimbabwean APEC isolates are different from those previously reported. Zimbabwean APEC isolates appear to be less pathogenic and may rely on environmental factors and stress in hosts to establish infection.

This study was conducted to determine the effect of maternally derived antibody (MDA) on live vaccine against infectious bursal disease. A total of 140 chicks selected from vaccinated parent stock were used in this investigation. In a preset vaccination schedule, blood samples were collected to check for the actual effect. It was noticed that on day 1 the chicks contained a high level (6400.54 ± 2993.67) of maternally derived antibody that gradually decreased below a positive level within 21 days (365.86 ± 634.46). It was found that a high level of MDA interferes with the vaccine virus, resulting in no immune response. For better immune response, it is suggested that the chickens should be vaccinated at day 21, as the uniformity of MDA is poor (coefficient of the variation [CV] > 30%), and boosted at day 28. Indeed, two vaccinations are necessary to achieve good protection against infectious bursal disease virus of the entire flock.

Glossina pallidipes salivary gland hyperplasia (GpSGH) syndrome caused by the salivary gland hyperplasia virus reduces the reproduction potential of tsetse flies, posing a serious threat for rearing of sufficient colonies for use of tsetse and trypanosome control using the sterile insect technique. This research was conducted in the Kaliti Tsetse Mass Rearing and Irradiation Centre in Ethiopia with the objective of studying the prevalence of GpSGH syndrome in laboratory colonies of G. pallidipes (Tororo and Arbaminch) reared for release in the implementation of the sterile insect technique and a field strain of G. pallidipes Arbaminch. Presence or absence of GpSGH was determined when pathological features of the salivary gland were revealed after dissection. The overall prevalence of GpSGH syndrome in laboratory colonies was 48.3% (747/1548) with a statistically significant (z = 17.30, p = 0.001) prevalence of 70.2% (544/775) in Arbaminch colonies and 26.26% (203/773) in Tororo colonies. The prevalence of GpSGH in laboratory flies fed according to the clean blood feeding protocol was 68.9% and 22.4% in Arbaminch and Tororo strains respectively. It was 70.5% and 27.2% respectively in laboratory colonies of Arbaminch and Tororo strains fed according to the standard membrane feeding protocol. The difference in prevalence of the disease between the two feeding protocols was not statistically significant in either Arbaminch (z = 0.361, p = 0.359) or Tororo (z = 1.22, p = 0.111) strains. The prevalence of SGH in wild G. pallidipes Arbaminch strain was 3% (15/500) and was significantly (z = 23.61, p < 0.001) lower than in the laboratory strain. The effect of age and density-related stress on the development of GpSGH was not statistically significant. The prevalence of GpSGH in the newly emerging (teneral) flies in the laboratory colonies was 66.7% and 20% in the Arbaminch and Tororo strains respectively. For all considered risk factors, the prevalence was much higher in G. pallidipes Arbaminch laboratory colonies.

Coxiella burnetii and Toxoplasma gondii are intracellular parasites that cause important reproductive disorders in animals and humans worldwide, resulting in high economic losses. The aim of the present study was to analyse the possible role of peridomestic small mammals in the maintenance and transmission of C. burnetii and T. gondii in the north-western African archipelagos of the Canary Islands and Cape Verde, where these species are commonly found affecting humans and farm animals. Between 2009 and 2013, 108 black rats (Rattus rattus) and 77 mice (Mus musculus) were analysed for the presence of Coxiella and Toxoplasma antibodies by enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence (IFA), respectively. Our results showed a wide distribution of C. burnetii and T. gondii, except for T. gondii in Cape Verde, in both rodent species. The overall seroprevalence of C. burnetii antibodies was 12.4%; 21.1% for Cape Verde and 10.2% for the Canary Islands. With respect to T. gondii, seropositive rodents were only observed in the Canary Islands, with an overall seroprevalence of 15%. Considering the fact that both pathogens can infect a large range of hosts, including livestock and humans, the results are of public health and veterinary importance and could be used by governmental entities to manage risk factors and to prevent future cases of Q fever and toxoplasmosis.

The seroprevalence of Toxoplasma gondii antibodies in a sample of 292 merino sheep farmed in a semi-intensive manner in the Overberg region of the Western Cape, South Africa, was investigated. Antibody seroprevalence was determined by enzyme-linked immunosorbent assay. Of the total sample, 23 sheep tested positive for T. gondii antibodies (8%; 95% CI: 4.7688-10.9846). There was no statistically significant relationship between seroprevalence and age of the sheep. The highest seroprevalence was found in sheep between 28 and 40 months old; a total of 19 sheep were seropositive by 40 months. No seropositive sheep were found in the age group between 16 and 28 months. The seroprevalence reported in this study is higher than what has previously been reported for the Western Cape (6%) and across South Africa on average (4.7%). As sheep farming is economically significant in South Africa, the presence of T. gondii amongst sheep may pose a production threat to the small-stock industry as well as to public health and food security. We therefore recommend further surveillance to identify high-risk animal populations so that local control measures can be put in place.

OBJECTIVE To evaluate effects of laser treatment on incisional wound healing in ball pythons (Python regius). ANIMALS 6 healthy adult ball pythons. PROCEDURES Snakes were sedated, a skin biopsy specimen was collected for histologic examination, and eight 2-cm skin incisions were made in each snake; each incision was closed with staples (day 0). Gross evaluation of all incision sites was performed daily for 30 days, and a wound score was assigned. Four incisions of each snake were treated (5 J/cm2 and a wavelength of 980 nm on a continuous wave sequence) by use of a class 4 laser once daily for 7 consecutive days; the other 4 incisions were not treated. Two excisional skin biopsy specimens (1 control and 1 treatment) were collected from each snake on days 2, 7, 14, and 30 and evaluated microscopically. Scores were assigned for total inflammation, degree of fibrosis, and collagen maturity. Generalized linear models were used to investigate the effect of treatment on each variable. RESULTS Wound scores for laser-treated incisions were significantly better than scores for control incisions on day 2 but not at other time points. There were no significant differences in necrosis, fibroplasia, inflammation, granuloma formation, or bacterial contamination between control and treatment groups. Collagen maturity was significantly better for the laser-treated incisions on day 14. CONCLUSIONS AND CLINICAL RELEVANCE Laser treatment resulted in a significant increase in collagen maturity at day 14 but did not otherwise significantly improve healing of skin incisions.