Immunogenicity of a pentavalent recombinant Escherichiacoli bacterin against enterotoxemia and botulism in sheep.

INTRODUCTION: Producing commercial bacterins/toxoids against Clostridium spp. is laborious and hazardous. Conversely, developing prototype vaccines using purified recombinant toxoids, though safe and effective, is both laborious and costly for application in production animals. OBJECTIVE: Considering that inactivated recombinant Escherichiacoli (bacterin) is a simple, cost-effective, and to be safe solution, we evaluated, for the first time, a pentavalent formulation of recombinant bacterins containing the alpha, beta, and epsilon toxins of Clostridiumperfringens and C and D neurotoxins of Clostridiumbotulinum in sheep. METHODS: Subcutaneously, 18 Texel sheep received two doses (200 µg of each antigen) of recombinant bacterin (n = 7) or purified recombinant antigens (n = 6) on days 0 and 28, while the control group (n = 5) did not receive an immunization. Sera samples from days 0 (before the 1st dose), 28 (before the 2nd dose), and 56, 84, and 112 were used for measuring IgG (indirect ELISA) and neutralizing antibodies (mouse serum neutralization). RESULTS: Both formulations induced significant levels of IgG against all five toxins (p < 0.05) up to day 112, with peaks at days 28 and 56 post-immunization. The expected booster effect occurred only for the botulinum toxins. The neutralizing antibody titers were satisfactory against ETX (≥2 IU/ml for both formulations) and BoNT-D [5 IU/ml (bacterin) and 10 IU/ml (purified)]. CONCLUSION: While adjustments are required, the recombinant bacterin platform holds great potential for polyvalent vaccines due to its straightforward, safe, and cost-effective production, establishing it as a user-friendly technology for the veterinary immunobiological industry.

Não constituintes da carcaça de cordeiros em distintas condições sexuais / Non-constituents of the carcass of lambs on different sexual conditions

O estudo foi realizado com objetivo de avaliar os efeitos da condição sexual nos pesos e rendimentos dos não constituintes da carcaça de cordeiros cruza Texel x Corriedale. Foram utilizados 46 machos divididos em três grupos: não castrados (n=15), castrados (n=17) e induzidos ao criptorquidismo (n=14). Foi adotado o delineamento experimental inteiramente casualizado com três tratamentos e número variável de repetições. Foi realizada análise de variância para avaliar o efeito da condição sexual sobre as características estudadas. Cordeiros castrados atingiram as condições estipuladas para o abate mais precocemente. Não castrados e induzidos ao criptorquidismo apresentaram pesos superiores de cabeça (kg), pele (kg), pênis (kg) e fígado com vesícula (kg). Não castrados apresentaram valores Como citar - disponível no site, superiores do conjunto pulmões com traqueia (kg) em relação na página do artigo. a animais castrados. Conclui-se que cordeiros não castrados e induzidos ao criptorquidismo apresentam pesos superiores de alguns componentes corporais quando terminados em campo nativo recebendo suplementação de 1% do peso corporal. Proporcionalmente, a condição sexual não interfere nos rendimentos dos componentes corporais de cordeiros Texel x Corriedale.(AU)

The study was carried out with objective to evaluate the effects of sexual condition on the weights and yields of nonconstituents of the carcass of Texel x Corriedale lambs. Forty-six males were used divided in three groups: uncastrated (n = 15), castrated (n = 17) and induced to cryptorchidism (n = 14). A completely randomized design with three treatments and variable number of repetitions was adopted, an analysis of variance was performed to evaluate the effect of sexual condition on the characteristics studied. Castrated lambs have reached the stipulated conditions for slaughter earlier. Uncastrated and induced to cryptorchidism presented higher weights of head (kg), skin (kg), penis (kg) and liver with gall bladder (kg). Uncastrated lambs presented higher values for lungs with trachea (kg) compared to castrated animals. It is concluded that uncastrated and induced to cryptorchidism lambs present higher weights of some body components when finished in native field receiving supplementation of 1% of body weight. Proportionally, the sexual condition does not interfere in the yields of the body components of Texel x Corriedale lambs.(AU)

Não constituintes da carcaça de cordeiros em distintas condições sexuais / Non-constituents of the carcass of lambs on different sexual conditions

O estudo foi realizado com objetivo de avaliar os efeitos da condição sexual nos pesos e rendimentos dos não constituintes da carcaça de cordeiros cruza Texel x Corriedale. Foram utilizados 46 machos divididos em três grupos: não castrados (n=15), castrados (n=17) e induzidos ao criptorquidismo (n=14). Foi adotado o delineamento experimental inteiramente casualizado com três tratamentos e número variável de repetições. Foi realizada análise de variância para avaliar o efeito da condição sexual sobre as características estudadas. Cordeiros castrados atingiram as condições estipuladas para o abate mais precocemente. Não castrados e induzidos ao criptorquidismo apresentaram pesos superiores de cabeça (kg), pele (kg), pênis (kg) e fígado com vesícula (kg). Não castrados apresentaram valores Como citar - disponível no site, superiores do conjunto pulmões com traqueia (kg) em relação na página do artigo. a animais castrados. Conclui-se que cordeiros não castrados e induzidos ao criptorquidismo apresentam pesos superiores de alguns componentes corporais quando terminados em campo nativo recebendo suplementação de 1% do peso corporal. Proporcionalmente, a condição sexual não interfere nos rendimentos dos componentes corporais de cordeiros Texel x Corriedale.

The study was carried out with objective to evaluate the effects of sexual condition on the weights and yields of nonconstituents of the carcass of Texel x Corriedale lambs. Forty-six males were used divided in three groups: uncastrated (n = 15), castrated (n = 17) and induced to cryptorchidism (n = 14). A completely randomized design with three treatments and variable number of repetitions was adopted, an analysis of variance was performed to evaluate the effect of sexual condition on the characteristics studied. Castrated lambs have reached the stipulated conditions for slaughter earlier. Uncastrated and induced to cryptorchidism presented higher weights of head (kg), skin (kg), penis (kg) and liver with gall bladder (kg). Uncastrated lambs presented higher values for lungs with trachea (kg) compared to castrated animals. It is concluded that uncastrated and induced to cryptorchidism lambs present higher weights of some body components when finished in native field receiving supplementation of 1% of body weight. Proportionally, the sexual condition does not interfere in the yields of the body components of Texel x Corriedale lambs.

Blood testosterone level and growth of castrated, uncastrated, and cryptorchid lambs / Nível sanguíneo de testosterona e crescimento de cordeiros castrados, não castrados e criptorquidas

The objective of this study was to evaluate the effects of sexual status on blood testosterone levels and its influence on lamb growth. A total of 49 Texel x Corriedale males, originating of single births, were divided into three groups: uncastrated (n = 16), castrated (n = 17) and cryptorchid (n = 16), in the State of Rio Grande do Sul, in extensive natural pasture, with feed supplementation after weaning. The effect of the sexual status was examined by analysis of variance. Uncastrated and castrated lambs showed higher body weight, thoracic perimeter, and body compactness between the 35th and 203th day of age. Uncastrated lambs had mean weight higher than cryptorchid lambs over the whole period. Cryptorchid lambs had an average weight gain greater than castrated lambs between the 203rd and 259th days. Castrated lambs had a higher body condition score on the 147th day than the cryptorchid lambs, and on the 175th and 203rd days than uncastrated and cryptorchid lambs. Blood testosterone concentrations were higher in the uncastrated and cryptorchid lambs on the 203rd and 231st days and in the overall mean. The findings of this study showed that, with advancing age, the sexual status affects the testosterone production, not showing differences regarding growth at young ages.(AU)

O estudo foi realizado com objetivo de avaliar os efeitos da condição sexual nos níveis sanguíneos de testosterona e sua influência no crescimento de cordeiros. Foram utilizados 49 machos cruza Texel x Corriedale, oriundos de partos simples, divididos em três grupos: não castrados (n=16), castrados (n=17) e induzidos ao criptorquidismo (n=16), criados na região do Bioma Pampa, no Estado do Rio Grande do Sul, em condições extensivas de pastagem natural, com suplementação alimentar após o desmame. Foi utilizada a análise de variância para avaliar o efeito da condição sexual. Cordeiros não castrados e castrados apresentaram valores superiores de peso corporal entre o 35º e o 203º dia de idade, assim como no perímetro torácico e compacidade corporal. Cordeiros não castrados foram superiores aos criptorquidas na média de peso no período total. Criptorquidas apresentaram ganho médio de peso superior aos castrados entre o 203º e 259º dias. Castrados apresentaram escore de condição corporal superior, no 147º dia em relação aos criptorquidas, e no 175º e 203º dias em relação a não castrados e criptorquidas. As concentrações de testosterona sanguínea foram superiores nos não castrados e criptorquidas no 203º e 231º dias e na média geral. Conclui-se que, com o avanço da idade, a condição sexual afeta a produção hormonal de testosterona não se observando diferenças em termos de crescimento em idades jovens.(AU)

Blood testosterone level and growth of castrated, uncastrated, and cryptorchid lambs / Nível sanguíneo de testosterona e crescimento de cordeiros castrados, não castrados e criptorquidas

The objective of this study was to evaluate the effects of sexual status on blood testosterone levels and its influence on lamb growth. A total of 49 Texel x Corriedale males, originating of single births, were divided into three groups: uncastrated (n = 16), castrated (n = 17) and cryptorchid (n = 16), in the State of Rio Grande do Sul, in extensive natural pasture, with feed supplementation after weaning. The effect of the sexual status was examined by analysis of variance. Uncastrated and castrated lambs showed higher body weight, thoracic perimeter, and body compactness between the 35th and 203th day of age. Uncastrated lambs had mean weight higher than cryptorchid lambs over the whole period. Cryptorchid lambs had an average weight gain greater than castrated lambs between the 203rd and 259th days. Castrated lambs had a higher body condition score on the 147th day than the cryptorchid lambs, and on the 175th and 203rd days than uncastrated and cryptorchid lambs. Blood testosterone concentrations were higher in the uncastrated and cryptorchid lambs on the 203rd and 231st days and in the overall mean. The findings of this study showed that, with advancing age, the sexual status affects the testosterone production, not showing differences regarding growth at young ages.

O estudo foi realizado com objetivo de avaliar os efeitos da condição sexual nos níveis sanguíneos de testosterona e sua influência no crescimento de cordeiros. Foram utilizados 49 machos cruza Texel x Corriedale, oriundos de partos simples, divididos em três grupos: não castrados (n=16), castrados (n=17) e induzidos ao criptorquidismo (n=16), criados na região do Bioma Pampa, no Estado do Rio Grande do Sul, em condições extensivas de pastagem natural, com suplementação alimentar após o desmame. Foi utilizada a análise de variância para avaliar o efeito da condição sexual. Cordeiros não castrados e castrados apresentaram valores superiores de peso corporal entre o 35º e o 203º dia de idade, assim como no perímetro torácico e compacidade corporal. Cordeiros não castrados foram superiores aos criptorquidas na média de peso no período total. Criptorquidas apresentaram ganho médio de peso superior aos castrados entre o 203º e 259º dias. Castrados apresentaram escore de condição corporal superior, no 147º dia em relação aos criptorquidas, e no 175º e 203º dias em relação a não castrados e criptorquidas. As concentrações de testosterona sanguínea foram superiores nos não castrados e criptorquidas no 203º e 231º dias e na média geral. Conclui-se que, com o avanço da idade, a condição sexual afeta a produção hormonal de testosterona não se observando diferenças em termos de crescimento em idades jovens.

Onset of reproductive activity of white and natural colored corriedale ewe labms

The objective of this study was to estimate differences in growth, plasma progesterone (P4) and age at puberty between white and natural colored Corriedale ewe lambs. Thirty ewe lambs with average age of 12 months were randomly allocated to genetic groups: white (WC, n = 15) and natural colored (NC, n = 15). Ewes were maintained under extensive grazing conditions on natural pasture, and herbage mass was estimated over a 28-day experimental period. Morphometric measurements (front and hind height, body length, thoracic perimeter, rump length and width, wool fiber length), body condition score (CC) and weight were taken at 28-day intervals. There was no effect of genetic group on body weight, average daily gain and morphometric measurements (P > 0.05). The WC ewe lambs had longer fiber length (P < 0.05). Plasma P4 was similar between genotypes (P > 0.05); however, it increased above 1ng ml-1 in NC from January onward and in WC from March onwards. Estrus was detected at the same time in both groups. The results of this study indicate that both genetic groups have similar growth patterns and ovarian activities.(AU)

Onset of reproductive activity of white and natural colored corriedale ewe labms

The objective of this study was to estimate differences in growth, plasma progesterone (P4) and age at puberty between white and natural colored Corriedale ewe lambs. Thirty ewe lambs with average age of 12 months were randomly allocated to genetic groups: white (WC, n = 15) and natural colored (NC, n = 15). Ewes were maintained under extensive grazing conditions on natural pasture, and herbage mass was estimated over a 28-day experimental period. Morphometric measurements (front and hind height, body length, thoracic perimeter, rump length and width, wool fiber length), body condition score (CC) and weight were taken at 28-day intervals. There was no effect of genetic group on body weight, average daily gain and morphometric measurements (P > 0.05). The WC ewe lambs had longer fiber length (P 0.05); however, it increased above 1ng ml-1 in NC from January onward and in WC from March onwards. Estrus was detected at the same time in both groups. The results of this study indicate that both genetic groups have similar growth patterns and ovarian activities.