RESUMEN

Despite the diagnostic capacity of ultrasonography (US) in cases of bovine enzootic hematuria (BEH), it has been underused in the medical clinic for ruminants. Studies comparing ultrasound findings in healthy animals (HA) with subclinical (SCH) and clinical (CH) BEH are scarce in the literature. As a result, the present work aims to describe the US findings of cattle at different stages of BEH evolution, evaluating the diagnostic capacity and precocity of the technique. The study was carried out on five rural properties in the municipalities of Rio Preto and Bom Jardim de Minas - MG, Brazil, using 46 dairy cattle, females over 18 months of age, evaluated and classified as G1/CH, G2/SCH and G3/HA, according to history, clinical examination and urinalysis, with subsequent ultrasound analysis of the bladder. The mean bladder wall thickness was 36.50 mm in G1/CH, 33.53 mm in G2/SCH and 37.93 mm in G3/HA. Irregular walls were observed in 53.33 % (8/15) of G1/CH, 27 0.78 % (5/18) of G2/SCH and 38.46 % (5/13) of G3/HA. Loss of the architecture of the urothelium layers was observed in 53.33 % (8/15) of G1/CH, 33.33 % (6/18) of G2/SCH and 38.46 % (5/13) of G3/HA. Multifocal and Grade I lesion were the most common. Ultrasonography allowed the identification of lesions in 38.46 % of animals that did not present hematuria and in 33.33 % of animals that presented occult blood and proved to be an efficient technique for detecting pre-clinical cases of BEH, allowing easy identification. and early onset of BEH cases.

RESUMEN

This study aims to evaluate the association between reproductive disorders and the main serogroups of Leptospira spp. in dairy herds. Blood samples from 216 cows from nine herds were collected for a Microscopic Agglutination Test (MAT), and a reproductive follow-up with ultrasonography was carried out monthly for at least 12 months. A total of 75 (16.5%) cows were reactive, while seroreactivity to a herd level ranged from 16.0% to 52.8%. Out of the nine herds, in five (55.0%) Sejroe was found to be the predominant serogroup and in four (45.0%) it was Icterohaemorrhagiae. The major reproductive problems identified were embryonic death (ED) and abortions. All herds presented ED and abortion was observed in three (33.3%). Herds with high seroreactivity (>20%) had more reproductive problems. Those with a predominance of Sejroe were associated with ED (P < 0.05), while those with Icterohaemorrhagiae were associated with abortion. The results show that different leptospiral strains lead to different reproductive problems, as well as showing that the main problem - ED - is caused by leptospirosis, particularly for those determined by strains of the serogroup Sejroe.

Asunto(s)

RESUMEN

For different ovine breeds to maximize their reproductive capacity in countries with tropical climate, it is important to evaluate their potential for thermal resilience and consequences on their reproductive traits. Therefore, the objective of this study was to evaluate the effect of thermal environment temperatures of climate seasons in a tropical climate region on the surface temperatures of the scrotum, testicular biometric characteristics, seminal quality and serum testosterone concentration of rams of different genotypes. Breeders of four different genotypes (Dorper, n = 8, Texel, n = 8, Santa Inês, n = 9 and Morada Nova, n = 8) were used throughout the four climate seasons. Higher thermal challenge was recorded in the spring and summer. In the summer increase in scrotal surface temperature was detected by infrared thermography (P < 0.05), mainly in the regions of the distal testicular pole and tail of the epididymis. The animals of the Texel genotype had higher rectal temperature in the summer. In spring, this genotype also had the highest testicular pole (32.2 ±â€¯0.5 °C; P < 0.05) and distal (29.9 ±â€¯0.4 °C; P < 0.05) temperatures and a higher mean testicular temperature (31.7 ±â€¯0.4 °C; P < 0.05). The Morada Nova genotype showed a higher surface temperature gradient between testicular poles (2.96 ±â€¯0.1 °C; P < 0.05), especially in spring. Genotype-dependent thermal sensitivity was detected for the thermal gradient between the testicular poles, reflecting the seminal quality. There was a positive correlation of the thermal gradient between testicular poles with sperm membrane integrity and negative correlation with total sperm defects. The Texel genotype showed less progressive motility and higher percentage of sperm defects. There was no difference in testosterone concentration between genotypes and in the different seasons (P > 0.05). Thus, the indigenous genotypes showed a greater capability to maintain the scrotum-testicular thermoregulation. Dorper animals resembled the indigenous sheep genotypes, in terms of seminal characteristics, unlike Texel animals, which showed lower adaptability and lower seminal quality.

Asunto(s)

RESUMEN

BACKGROUND: Staphylococcus aureus is associated with chronic mastitis in cattle, and disease manifestation is usually refractory to antibiotic therapy. Biofilm production is a key element of S. aureus pathogenesis and may contribute to the treatment failure that is consistently reported by veterinarians. Minas Gerais State is the largest milk-producing state in Brazil, and the characterization of bacterial isolates is an important aspect of disease control for dairy farmers. Here, we investigated the potential of S. aureus isolated from bovine mastitis to produce slime and biofilm in a skim-milk medium and classified the isolates according to their agr type. RESULTS: Slime was detected using the Congo Red agar (CRA) test in 35.18% (19/54) of the strains; however, 87.04% (47/54) of the strains were considered biofilm-positive based on crystal violet staining. Compared to TSB supplemented with 0.25% glucose, skim milk significantly increased the production of biofilm, but this effect was only observed in slime-producing strains. The bacteria belonged to agr groups I (12/54), II (34/54), III (6/54), and IV (2/54), and bacteria in agr group III were found to be stronger biofilm producers than those in groups I and II. Again, milk had a significant influence only on slime-positive agr I and II isolates, revealing an association between milk and slime. CONCLUSIONS: The present study demonstrated that skim-milk medium and slime production are two factors that together influence biofilm formation by bovine strains of S. aureus. A predominance of bacteria belonging to agr group II was observed, and bacteria from agr group III showed the highest proportion of biofilm producers. The majority of bacteria characterized in this study formed biofilm in milk, which suggests that biofilm formation has an important role in the virulence of S. aureus isolated from bovine intramammary infections.

Asunto(s)

RESUMEN

With the purpose of identifying management factors that may be influencing the prevalence of bovine tuberculosis under tropicalconditions, namely in Rio de Janeiro, Brazil, 1632 cows were tested through the single cervical tuberculin test. A questionnairewas completed for each herd. A total of 207 positive reactions were observed, corresponding to 12.7% of the studied cattle. Themain factors observed that may be influencing the prevalence of bovine tuberculosis on those farms were the absence orreduced veterinary assistance and the herd size. The presence of adequate cattle houses and the highly intensive managementare also considered to be likely to influence the prevalence of the disease. Under tropical conditions, a tuberculosis controlprogram, in addition to the test-and-slaughter control method, should include an investigation of herd management practices totry to identify factors that are likely to influence the prevalence of the disease.