Austral Journal of Veterinary Sciences
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Renal Stephanuriasis: Gross and microscopic findings in naturally-infected pigs from St. Kitts, West Indies
Get PDFStephanurus dentatus, the kidney worm of swine, is an important nematode parasite in outdoor swine populations worldwide. Infection is most common in tropical and subtropical areas and results in decreased weight gain and condemnation of edible parts invaded by migrating larvae. Worms reach sexual maturity within nodules at the peri-ureteral fat which communicate with the ureter and eggs are eliminated in the urine. At the St.Kitts abattoir, the kidneys of 10 pigs with gross lesions of stephanuriasis were examined microscopically. Parasitic tracts surrounded by areas of hemorrhage and inflammation were present in the fibro-adipose tissue around the ureters, renal pelvis and, rarely, within the renal parenchyma. Morulated eggs were found within nodules containing encysted worms. Due to the lengthy development of the parasite within the definite host, the finding of patent stephanuriasis in slaughterhouse pigs is unusual and likely the result of poor local management practices which lead to reduced weight gains, delays in the attainment of market weight and the frequent slaughtering of one year old pigs
Prevalence and distribution of intestinal parasites in stray dogs in the northwest area of Mexico
Get PDFZoonotic parasitic infections are a major global public and veterinary health problem and widespread among stray dogs. The objective of this study was to establish the prevalence of intestinal parasites in stray dogs in the urban, rural and coastal areas of Mexicali County in northwest Mexico. In 2014, from January to December, 380 stray dogs were captured. The entire small intestine, cecum and faeces samples were collected and examined by using simple zinc sulfate flotation and Lugol’s solution staining. Data were statistically analysed. Overall, about 21.5% of examined dogs were found positive for intestinal parasites. Toxocara canis was the most frequent detected parasite, with a prevalence of 7.1%, followed by Toxascaris leonina (5.5%), Cystoisospora spp. (5.0%), Taenia spp. (3.9%) and Dipylidium caninum (2.8%). Dogs were more frequently found to be infected with a single genus of intestinal parasite (18.7%) than co-infected (2.8%). Intestinal parasites were more prevalent in samples from the coastal area (25%) than in those from the rural (24.4%) and urban (20.6%) areas, however, only statistical association was found between capture area and specific intestinal parasitic infection. There were significant differences in the prevalence of taeniasis among two age groups (P<0.01). A seasonal peak of prevalence for intestinal parasitic infections was found during spring (P<0.05), corresponding with a seasonal peak of prevalence of T. canis (P<0.05). The wide range of isolated parasites indicated that people residing in this area are at risk of exposure to these potentially hazardous zoonotic pathogens
Evaluation of two diluents for the storage of fresh and cryopreserved semen of Harris hawk (Parabuteo unicinctus)
Get PDFSeminal storage, both fresh and cryopreserved, has contributed to the reproduction of wild birds in captivity, however, a method of predicting the fertilization capacity is needed. Indicators of the sperm acrosome reaction (AR) have been associated with its fertilization capacity. Therefore, the aim of this study was to evaluate the in vitro AR of fresh and cryopreserved Harris hawk sperm using Beltsville Poultry Semen Extender (BPSE) and Lake as diluents. 64 ejaculates were obtained and examined fresh and after thawing. The sperm basic evaluation for each ejaculate was made using eosin-nigrosin, while the ability of AR was assessed by coincubation with perivitelline layer (PVL). Sperm motility of fresh semen was higher (P<0.05) in fresh semen in BPSE (37.9±1.7) than in Lake (30.9±1.7) diluent. However, the motility decreased (P<0.05) in both diluents after thawing. For fresh semen, the percentage of sperm that underwent an AR without incubation with PVL was higher (P<0.05) with BPSE (14.1±1.7) than with Lake (6.8±2.5) diluent, however, AR was similar between tow diluents (P>0.05) after thawing. The percentage of sperm that underwent an AR when incubated with PVL post thawing in Lake (45.4±2.7) was lower (P<0.05) than that of fresh semen (55.3±3.1), whereas there were no differences (P>0.05) with BPSE. It is concluded that Lake diluent was more efficient for fresh seminal storage, while BPSE diluent was more efficient for seminal cryopreservation in Harris hawk
Testicular echotexture is not a viable method to indirectly evaluate the spermatogenic parameters in Nelore bulls
Get PDFeters. Forty one bulls aged 3-5 years, with body weight of 510.2 ± 21.61 kg were selected for the study. The animals were subjected to ultrasonography, using a portable device coupled with a linear transducer at a frequency of 7.5 MHz. Immediately afterwards they were castrated and the testicular tissue was treated with Karnovsky fixative. Next, the fragments were embedded in glycol methacrylate and stained with toluidine blue–1% sodium borate solution. The average pixel intensity in the testicular parenchyma was determined for 1,600-mm2 surface sections. The right and left testicles and the area between the two testicles resulted in average pixel intensities of 105.22 ± 13.58, 107.95 ± 12.82, and 106.59 ± 11.43, respectively. The efficiency coefficient of spermatogonial mitosis was 19.74; meiotic index was 2.63, and overall yield of spermatogenesis was 52.0. No correlation (P>0.05) was observed between testicular echotexture and any of the measured morphometric parameters. These results suggest that testicular echotexture was not a viable method for the indirect analysis of cellular population in the seminiferous epithelium, intrinsic spermatogenic performance, or the Sertoli cell index in Nelore bulls
Ruminal acidosis: strategies for its control
Get PDFRuminal acidosis in ruminants is a metabolic disorder of gastrointestinal origin that occurs in animals with a high feed intake of cereal grains diets, which affect the performance. According to clinical manifestations it can be classified as: a) acute lactic acidosis with prolonged exposure to ruminal pH ≤ 5.0, triggering a systemic acidosis, with clinical manifestations and changes in biochemical patterns, starting the first twelve hours of ruminal acidosis and it takes 48 to 120 hours to reestablish, b) subacute ruminal acidosis (SARA), it has no clinical manifestations, rumen pH decreases in a range of 5.5 to 5.0 and is held for 111 to 180 minutes in 24 hours, this decrease causes an imbalance in the ruminal metabolism, as well as the fluid balance. Ruminal acidosis can be prevented by adding sodium bicarbonate to the ration, or zootechnic additives such as Saccharomyces cereviseae and Megasphaera elsdenii as well as essential oils (cinnamaldehyde and eugenol). It is also important to consider the forage/concentrate ratio, the forage particle size, the NDF content of the ration, as well as the cereal’s rate of degradation in the rumen. The objective of this review was to address the ruminal acidosis pathophysiology, its effects on animal welfare and control strategies to minimise the detrimental impact on animal production
The effects of Spirulina platensis (Arthrospira platensis) and Saccharomyces cerevisiae on the distribution and cytokine production of CD4+ and CD8+ T-lymphocytes in rabbits
Get PDFNatural additives have become one of the most alternative immune enhancer nowadays. In particular, Spirulina platensis (Arthrospira platensis) (SP) and Saccharomyces cerevisiae (SC) have been used for improving the immune system and quality of life. The aim of this study was to regulate the immune effect of S. cerevisiae and S. platensis (A. platensis) combination. Forty male New Zealand white rabbits, aged 5-6 weeks, were analysed in 4 groups: Control (basal diet); SC (added 3 g/kg diet), SP (added 5% of the diet); SC and SP (added 3 g/kg SC and 5% SP of the diet). The entire experiment lasted 90 days. Blood samples were obtained by ear venipuncture on the 90th day. The CD4+ and CD8+ T lymphocyte values were determined by flow cytometry and cytokines (IFN-γ and IL-4) were determined by ELISA. According to the results, there were no significant differences in the expression of cytokines, but serum CD4+/CD8+ increased in the animals fed SP and SC+SP supplemented diets (3 g/kg and 5% of the diet, respectively). It was concluded that S. platensis (A. platensis) may be used as an immune enhancer, although further studies are needed to clarify the effects of spirulina supplement on immunity
Impact of dietary inclusion of clinoptilolite as substitute of soybean meal on growth performance, dietary energetics and carcass traits of feedlot ewes fed a corn-based diet
Get PDFForty ewes (31.725±1.44 kg initial LW) were used to evaluate the effects of clinoptilolite (ZEOL) supplementation (0, 1, 2, and 3%, DM basis of diet) as substitute of soybean meal (SBM) in a finishing corn-based diet on growth performance, dietary energetics, and carcass traits. The experiment lasted 56 days. For each percentage of substitution of SBM by ZEOL, the crude protein and net energy (NE) of basal diet were decreased in 0.37 percentage units and 0.02 Mcal/kg, respectively. There were no treatment effects (P>0.27) on average daily gain (ADG), dry matter intake (DMI), and gain efficiency (ADG/DMI). Dietary NE was not affected by ZEOL supplementation (P≥0.69). However, due to the inertness (it does not provide energy) of ZEOL, itself, the ratio of observed-to-expected dietary NE linearly increased (P=0.02) and the ratio of observed-to-expected DMI linearly decreased (P=0.02) with ZEOL supplementation. Clinoptilolite supplementation linearly decreased fat thickness (P=0.02) and visceral fat (P=0.03) with no effects (P≥0.12) on other carcass measures or the organ tissue weights (as proportion of g/kg of empty body weight). Dilution of CP and dietary NE by substitution of SBM by zeolite up to 3% did not negatively affect growth performance and carcass traits. This result suggests that the inclusion of up to 3% of clinoptilolite in substitution of a high protein source (SBM) on finishing diets has a positive effect on the utilization of dietary energy
Ruminants are not a reservoir of enteroaggregative Escherichia coli
Get PDFEnteroaggregative Escherichia coli (EAEC) causes both acute and persistent diarrhoea among children and adults in developing and developed countries. In addition, the large outbreak of food-borne illness in Europe in the summer of 2011 was caused by a verotoxin-producing EAEC O104:H4 strain. The public health threat posed by EAEC makes it important to identify animal reservoirs that might lead to epidemics in humans. Based on only one study in sheep and a few in cattle, researchers have suggested that EAEC are not found in ruminants. To expand the available data on this question, the present study applied polymerase chain reaction to faecal samples from 920 cattle, sheep and goats to detect EAEC. None of the samples tested positive for any of the EAEC genes tested, suggesting that goats, like cattle and sheep, are unlikely to be a significant reservoir of EAEC
Effects of two platelet-rich gel supernatants at two concentrations on healthy cartilage explants from horses
Get PDFPlatelet-rich plasma is used as a treatment of arthropathies in horses. However, there is lack of in vitro information about the mechanism of action of this substance and its effects on healthy cartilage of these animals. The aims were: (1) to evaluate the effects at 48 and 96 h of two concentrations (25 and 50%) of leukocyte- and platelet-rich gel (L-PRG) and pure platelet rich gel (P-PRG) supernatants on the production/degradation in normal cartilage explants (CEs) of platelet-derived growth factor isoform BB, transforming growth factor beta-1, tumour necrosis factor alpha, interleukin (IL) 4 (IL-4), and IL-1 receptor antagonist (IL-1ra); and (2) to study possible correlations of these molecules with their respective PRG supernatant treatments. CEs from six horses were cultured for 96 h with L-PRG and P-PRG supernatants at 25 and 50% concentrations, respectively. CE culture media were changed each 48 h and used for determination, by ELISA, of the molecules. L-PRG and P-PRG supernatants at 25 and 50% concentrations influenced the molecular anti-inflammatory profile of CE groups cultured with these substances. 50% L-PRG supernatant produced the most robust pro-inflammatory effects when compared to the CE control group and the CE group treated with the other PRG supernatant concentrations. In general, PRG supernatants induced pro-inflammatory effects in normal CEs
Evaluation of a new vaccine against Staphylococcus aureus mastitis in dairy herds of southern Chile. I. Challenge trial
Get PDFS. aureus is the most frequently isolated mastitis pathogen in southern Chile. Hygiene during milking time and DCT have not been successful to control this pathogen. Vaccination has been suggested as a useful tool to combat mastitis and several vaccines have been developed and evaluated worldwide. This study presents the results of a pilot trial to evaluate the effects of a new vaccine produced in Chile against S. aureus mastitis on udder health, humoral immune response, and milk production after an experimental intramammary challenge with a heterologous S. aureus strain. Four 2 mL doses of the vaccine were administeredintramuscularly to five pregnant heifers free of IMI infections, using another five heifers as controls. Ten days after last immunisation two mammary quarters of all heifers were challenged with a pathogenic strain of S. aureus. Heifers were monitored for clinical signs, bacterial count, SCC, differential leukocyte count in blood, S. aureus antibody, and milk yield during 14 days after challenge. No systemic effects were observed in any of the challenged heifers, and severe clinical cases were only observed in the control group. The SCCs were always higher in heifers of the control group. The challenged quarters of the control group yielded the highest counts of S. aureus, but no significant difference was observed between vaccinated and non-vaccinated groups. Serum antibody titres were twice as high in the vaccinated group compared to the control group, and average milk yield reduction was lower in the vaccinated group. In conclusion, this vaccine was able to stimulate the humoral immune response of vaccinated heifers which could have a beneficial effect against new IMI by S. aureus and help to combat this mastitis pathogen