No abstract

In order to determine the role of Mycoplasma spp, Ureaplasma diversum and BHV-1 as causal agents of Granular Vulvovaginitis Syndrome in Nelore heifers raised under tropical conditions and based on the hypothesis that stressful conditions during puberty or breeding season would be a determinant factor for the infection, 340 heifers not vaccinated against BHV-1 were divided in Post-pubertal, in the beginning of the first breeding season, and Pubertal heifers. The vaginal lesion score (VLS) Grade 1 to 4 was giving according to lesion area and severity. Vaginal mucus was used to isolate Mycoplasma spp., Ureaplasma diversum and BHV-1. The predominant VLS was 2. No sample was positive for BHV-1; 48% were positive for Mycoplasma spp., Ureaplasma diversum, or both, with predominance of Ureaplasma diversum. Serum neutralization for BHV-1 showed more positive animals in pubertal group (23%); 3 of the paired sera demonstrated seroconversion. These data indicated that post-pubertal and pubertal Nelore heifers raised under extensive conditions are more susceptible to Mycoplasma spp. and Ureaplasma diversum. The hypothesis that the stress of pubertal period could lead to an acute vaginal infection by HBV-1 was not proofed.

O Ureaplasma diversum é um patógeno oportunista do trato genital dos bovinos que causa surtos de vulvovaginite granular, seguidos de abortamento e redução da eficiência reprodutiva do rebanho. O presente estudo foi desenvolvido com o objetivo de avaliar a relação entre a extensão e a gravidade das lesões de vulvovaginite observadas com o isolamento de Ureaplasma diversum em amostras colhidas diretamente da mucosa vulvovaginal, em fêmeas de aptidão leiteira repetidoras de estro no estado de Alagoas, Brasil. A avaliação da extensão e severidade das lesões foi feita em 93 vacas com histórico de repetição regular de estro após três ou mais inseminações artificiais, seguindo-se a seguinte metodologia de classificação: graus de 0 a 4, sendo 0=sem lesões; 4=lesões severas, com hemorragia e necrose. Dos 93 animais avaliados, 17,2% apresentavam lesão grau 0; 51,61% grau 1; 29,03% grau 2; 2,16% grau 3 e nenhum animal mostrou lesão de grau 4. Foi colhido muco vulvovaginal de 24 vacas, escolhidas aleatoriamente, para processamento bacteriológico, encontrando-se 41,67% das amostras positivas para Ureaplasma diversum. O isolamento do agente esteve positivamente relacionado à presença de lesões na mucosa vulvovaginal, especialmente àquelas de grau 1. Os resultados deste estudo indicam que o Ureaplasma diversum deve ser considerado como agente responsável por queda na eficiência reprodutiva, promovendo retorno ao estro, provavelmente em conseqüência de mortalidade embrionária.

An experiment was carried out with 630 oneday-old chicks to evaluate the effects of organic acids when birds were experimentally inoculated with Salmonella Typhimurium. Liver damage and the persistence of the bacterium in the organs were evaluated as well. Broilers were distributed in a completely randomised experimental design in a 3×2 factorial arrangement of six treatments with seven replicates of 15 birds each. Birds were inoculated with saline solution or the bacterium via gavage at 1 day of age, or were offered a feed containing or not the organic acid blend for the period of 7 to 14 days of age. A dose of 5.0x10 2 colony-forming units (CFU)/0.5 mL of Salmonella Typhimurium was used for inoculation both via gavage and feed. The parameters evaluated are weight, liver histopathology, liver and serum biochemistry, and bacteriological analyses of the caeca, crop, spleen, and liver and heart pool. At 21 and 28 days of age, the liver of the non-inoculated groups was significantly lighter as compared to the other treatments. Birds fed organic acids presented lower bacterial isolation rates in all organs tested. Birds inoculated in the crop and treated with organic acids presented lower E. coli CFU counts (P<0.05). Birds inoculated with Salmonella presented significant changes (P<0.05) in liver enzymes, as detected by serum biochemistry, and in liver histopathology. It was concluded that organic acids effectively controlled Salmonella Typhimurium and did not cause any liver damage.

The Girolando breed is used in pasture-based dairy production systems in Brazil to associate the high production of Bos taurus to the rusticity and thermal adaptation of Bos indicus. This study was designed to evaluate the physiological response to a gonadotropin-releasing hormone (GnRH)-prostaglandin F2α (PGF2α)-GnRH protocol to synchronize the ovulation in 40 Girolando heifers of a pasture-based dairy production system and its relationships with the temperature and humidity index (THI) during the dry (DS) and rainy season (RS) in the tropical savannah-Brazil's cerrado biome. Responses were characterized by follicular and corpus luteum number and diameter, ovulation (D9), and pregnancy rates after first AI. Total follicle number (8.1 ± 0.3 × 8.8 ± 0.3), D9 ovulatory follicle diameter (11.9 ± 0.4 × 10.1 ± 0.4 mm), corpus luteum diameter (8.6 ± 1.3 × 3.9 ± 1.5 mm), corpus luteum score (3.7 ± 0.8 × 1.8 ± 1.0), corpus luteum diameter after AI (9.6 ± 1.6 × 3.9 ± 1.5 mm), and corpus luteum score after AI (3.2 ± 0.4 × 0.9 ± 0.6) in DS and RS differed (P < 0.01). D9 ovulation rate was 40 % (DS) and 20 % (RS), without differences (P > 0.05). Pregnancy rate was 45 % (DS) and 11 % (RS), with differences (P < 0.01). THI differed between DS and RS (P < 0.01). THI may interfere in the follicular and luteal dynamics and in the response of Girolando heifers to the GnRH-PGF2α protocol in the tropical savannah, thus reducing the chances of pregnancy at the first artificial insemination.