Passive immunity in foals born from mares vaccinated against Theileira equi and Streptococcus equi subspecies equi / Imunidade passiva em potros provenientes de éguas vacinadas contra Theileira equi e Streptococcus equi subspécie equi

The aims of this study were: 1) determine total specific IgG and subisotypes in serum and colostrum of pregnant mares vaccinated against Theileria equi and Streptococcus equi subspecies equi; 2) determine total specific IgG and subisotypes in foals born from these mares. In mares, the highest total serum IgG value for T. equi was at 335 days of gestation declining 30 days postpartum, while for S. equi was at 328 days of gestation remaining high up to 30 days postpartum. Transfer of passive immunity against both antigens was observed with specific IgG values in colostrum and foals' serum proportional to mares' values. The most detected specific IgG subisotypes were IgG3/5 and IgG4/7 for both antigens. Foals born from mares immunized with T. equi kept maternal IgG values until 2 months of age, while those born from mares immunized with S. equi kept maternal IgG values until 3-4 months of age. These results suggest that foals should be vaccinated after this period.

Os objetivos deste estudo foram: 1) determinar IgG total específica e seus subisotipos no soro e colostro de éguas vacinadas contra Theileria equi e Streptococcus equi subspécie equi; 2) determinar IgG total específica e seus subisotipos em potros provenientes dessas éguas. Em éguas vacinadas contra T. equi, o maior nível sérico de IgG total específico ocorreu aos 335 dias de gestação, decaindo 30 dias pós parto, enquanto nas vacinadas contra S. equi, ocorreu aos 328 dias de gestação e manteve-se pelo mesmo período. A avaliação de IgG total específica no colostro de éguas vacinadas demonstrou níveis de IgG proporcionais aos títulos do soro materno. Os isotipos de IgG mais detectados foram IgG3/5 e IgG4/7 para ambos antígenos avaliados. Potros provenientes de éguas vacinadas com antígeno de T. equi mantiveram os níveis de IgG específica até dois meses de idade, enquanto potros provenientes de éguas vacinadas com antígeno de S. equi mantiveram por três a quatro meses, sugerindo que esse seja o período ideal para início do esquema vacinal em potros.

Changes in cholesterol, triglycerides and body composition in pregnant mares

Background: Mares are very different from other species during pregnancy, and studies on the physiologicalchanges of this period are important. During late pregnancy, the distribution of weight and body fat are oftenused as indicators of adequate nutrition. This is a physiological period that results in an increase in metabolicdemand. There is a tendency for the Criollo breed to have a higher body condition score that becomes moreevident during pregnancy, a period when mares tend to gain more weight. The current study monitored serumcholesterol and triglyceride levels in pregnant mares during late gestation to determine a possible correlationwith the distribution of fat or body weight.Materials, Methods & Results: Four body parameters of 34 Criollo-type mares in late gestation were evaluated: body weight measured with a weight scale, body weight using a commercial weight tape, total body fatand fat thickness and the serum levels of total cholesterol and triglycerides. The fat thickness was measuredin an ultrasound device and the prediction of total body fat was calculated using an equation. According to thedays prior foaling, biometric monitoring and blood collection were carried out in five periods: F-90 (± 90 daysprior to foaling) n = 33; F-60 (± 60 days prior to foaling) n = 33; F-30 (± 30 days prior to foaling) n = 31; F-15(± 15 days prior to foaling) n = 29 and Foaling (at day of foaling) n = 14. Mares were monitored daily andaccompanied foaling was also performed, ensuring collection at the right time. Comparisons of means wereperformed between variables in addition to the Pearson correlation test. Statistical significance was establishedat P < 0.05. There was no difference in relation to the period in body composition measurements (P > 0.05). Astrong positive correlation was observed between the average weights (P < 0.001). The fat thickness showeda correlation between the weights (P < 0.01). There was no correlation with...(AU)

Genetic parameters of morphometric measurements in Criollo horses.

The aim of this study was to estimate the genetic parameters for the morphometric measurements of withers height (WH), thoracic circumference (TC) and cannon bone circumference (CBC) of Criollo horses, stratified for maternal and paternal effects. Statistical genetic design of factor crossings was used to evaluate the offspring of full siblings and half-siblings. Fifty stallions were selected (n = 50) who had been crossed with six mares each (n = 6), to provide 300 parental pairings in which two offspring were born per mare (n = 600). WH in females and TC in males were highly influenced by additive genetic effects, while the other morphometric measures were found to be closely related to the general effects of the environment. WH had the greatest additive genetic influence on female offspring (47.06%), while TC presented the greatest additive genetic influence on male offspring (58.73%). When comparing the parental influence on the morphometric characteristics evaluated, TC and CBC had greater additive genetic influence from maternal effects, regardless of offspring sex. However, the WH in female offspring showed greater maternal additive genetic contribution, while in males this characteristic presented greater paternal additive genetic influence. For WH in male offspring, narrow sense heritability ( h r 2 : 0.26) was more influenced by paternal effects, while for WH in females ( h r 2 : 0.47), TC in females ( h r 2 : 0.08) and males ( h r 2 : 0.59), and CBC in females ( h r 2 : 0.07) and males ( h r 2 : 0.05) the maternal effects were the most important. Therefore, the phenotypic expression of WH in males and females and TC in males is influenced by the additive genetic effect of the genes. On the other hand, the TC in female progenies and CBC in progenies of both sexes are closely related to the effects of the environment. The results obtained in this study could be useful in the selection process of Criollo horses.

Changes in cholesterol, triglycerides and body composition in pregnant mares

Background: Mares are very different from other species during pregnancy, and studies on the physiologicalchanges of this period are important. During late pregnancy, the distribution of weight and body fat are oftenused as indicators of adequate nutrition. This is a physiological period that results in an increase in metabolicdemand. There is a tendency for the Criollo breed to have a higher body condition score that becomes moreevident during pregnancy, a period when mares tend to gain more weight. The current study monitored serumcholesterol and triglyceride levels in pregnant mares during late gestation to determine a possible correlationwith the distribution of fat or body weight.Materials, Methods & Results: Four body parameters of 34 Criollo-type mares in late gestation were evaluated: body weight measured with a weight scale, body weight using a commercial weight tape, total body fatand fat thickness and the serum levels of total cholesterol and triglycerides. The fat thickness was measuredin an ultrasound device and the prediction of total body fat was calculated using an equation. According to thedays prior foaling, biometric monitoring and blood collection were carried out in five periods: F-90 (± 90 daysprior to foaling) n = 33; F-60 (± 60 days prior to foaling) n = 33; F-30 (± 30 days prior to foaling) n = 31; F-15(± 15 days prior to foaling) n = 29 and Foaling (at day of foaling) n = 14. Mares were monitored daily andaccompanied foaling was also performed, ensuring collection at the right time. Comparisons of means wereperformed between variables in addition to the Pearson correlation test. Statistical significance was establishedat P 0.05). Astrong positive correlation was observed between the average weights (P < 0.001). The fat thickness showeda correlation between the weights (P < 0.01). There was no correlation with...