ResumoEste trabalho teve como objetivos descrever a diarreia e a infecção por parasitas e, avaliar a ocorrência de falha na transferência de imunidade passiva e de Escherichia coli enteropatogênica/enteroinvasiva em bezerras do nascimento aos cem dias de idade, criadas em sistema de abrigo individual em piquete. As fezes coletadas, semanalmente, durante o período de setembro de 2009 a junho de 2011 foram examinadas por meio das técnicas de centrífugo-flutuação em solução saturada de açúcar e centrífugo-sedimentação em formol-éter. O teste de coagulação pelo glutaraldeído a 10% foi utilizado para verificar a transferência de imunidade passiva. A identificação bacteriológica foi realizada a partir de isolamentos em meios específicos. Cento e dezoito bezerras foram acompanhadas, totalizando 1457 amostras fecais. As taxas de incidência de diarreia e de infecção por Cryptosporidium, G. intestinalis, Eimeria e helmintos foram respectivamente 25,7; 13,2; 16,6; 26,9 e 16,7 casos novos por 100 bezerrassemana. A média de idade de bezerras que apresentaram diarreia foi 54,2±26,6, quando eliminaram oocistos de Cryptosporidium foi de 52,6±26,1, cistos de G. intestinalis 40,1±20, oocistos de Eimeria 49,5±21,8 e ovos do tipo Strongylida 64,9±22,3 dias. Em nenhuma amostra a intensidade de infecção por Cryptosporidium e Giardia foi classificada como alta. Amostras de fezes de 62 bezerras foram submetidas à análise bacteriológica e nenhuma cepa foi caracterizada como E. coli enteropatogência/ enteroinvasiva. Em 69,6% das bezerras, a quantidade de imunoglobulinas no sangue foi satisfatória. Apesar da alta incidência de diarreia, a letalidade foi baixa, possivelmente devido pouca virulência dos bioagentes e às baixas intensidades das infecções, assim como, aos sistema de administração de colostro e de criação adotado na propriedade. A semelhança entre a idade média das bezerras com diarreia e aquelas que eliminaram oocistos de Cryptosporidium spp. indica que provavelmente este bioagente, dentre os pesquisados, é o principal responsável pelos quadros diarreicos observados. Palavras-chave: Estudo longitudinal, sistema de criação de bezerrros, colostro

910Pesq. Vet. Bras. 29(11):910-912, novembro 2009 RESUMO.-[Ineficácia do sulfóxido de albendazole e da ivermectina no tratamento da otite parasitária bovina causada por nematóides rhabditiformes.] O objetivo deste estudo foi avaliar a eficácia do sulfóxido de albendazol administrado oralmente e da ivermectina "pour-on" no tratamento da otite parasitária bovina causada por nematóides rhabditiformes. Dezoito vacas Gir apresentando otite clínica foram divididas em três grupos de seis animais cada. O primeiro não recebeu tratamento (grupo controle). O segundo foi tratado com ivermectina "pouron" a 0,05% na dose de 500μg/kg de peso vivo. O terceiro grupo foi tratado com sulfóxido de albendazol oral a 6% na dose 6,0mg/kg. Os condutos auditivos de todos os animais foram reexaminados nos dias 7 e 21 pós-tratamento. Os animais do grupo controle permaneceram infectados nos dias de observação. O tratamento com ivermectina não demonstrou eficácia alguma para os dias 7 e 21 pós-tratamento. O tratamento com sulfóxido de albendazol obteve 16,7 e 25% de eficácia nos dias 7 e 21, respectivamente. Mais estudos são necessários para determinação de tratamentos eficazes para tal doença parasitária, especialmente através de vias alternativas de administração, por causa de seu significante impacto na criação de Bos taurus indicus nas Regiões Tropical e Subtropical. The purpose of this study was to evaluate the efficacy of orally administered albendazole sulphoxide and pour-on ivermectin for the treatment of bovine parasitic otitis caused by rhabditiform nematodes. Eighteen Gyr cows presenting clinical otitis were divided in three groups with six animals each. The first one did not receive any treatment (control group). The second one was treated with 0.5% pour-on ivermectin, 500μg/kg of body weight, and the third group was treated with oral 6% albendazole sulphoxide, at 6.0mg/kg. Both ear canals of each animal were reexamined on days 7 and 21 post treatment. The animals in the control group remained infected throughout the days of observation. Ivermectin treatment did not show effectiveness on days 7 or 21 post treatment. The albendazole sulphoxide treatment had an efficacy of 16.7 and 25% on days 7 and 21, respectively. Further studies are required to assess an effective treatment for this parasitic disease, especially via alternative administration routes, because of its significant impact on Bos taurus indicus cattle breeding in Tropical and Subtropical Regions. Inefficacy of albendazole

RESUMO -o objetivo deste trabalho foi avaliar o desempenho de vitelos recebendo leite integral ou sucedâneo do leite especial para vitelos. Foram utilizados 30 bezerros, do nascimento aos 160-170 kg de peso vivo, distribuídos nos seguintes tratamentos experimentais: I -leite integral, II -leite integral até os 100 kg de peso vivo e, a partir daí, o aumento na quantidade de dieta líquida foi feito com o sucedâneo de terminação, adicionado ao leite, até o abate e III -leite até o 10 o dia de vida e, a partir daí, o sucedâneo inicial até atingir 100 kg de peso vivo, passando, então, para o sucedâneo de terminação, até o abate. Não houve diferença significativa entre os tratamentos para o ganho de peso médio diário (NS), a idade de abate (P=0,06701) e o rendimento de carcaça (P=0,21527); entretanto, os animais do tratamento III, que receberam o sucedâneo de leite, apresentaram consumo de matéria seca significativamente maior (P=0,00055) e, conseqüentemente, pior conversão alimentar (P=0,00021). Não houve diferença entre tratamentos para o número de dias com diarréia e a incidência de corrimento nasal foi insignificante. Seria economicamente vantajoso utilizar o sucedâneo comercial para vitelos, testado neste ensaio, se o preço do kg do produto (pó) fosse 6,4 vezes menor que o preço de um litro de leite integral. Palavras-chave: bezerros, desempenho, sucedâneos do leite, vitelos Test of a Milk Replacer for Veal CalvesABSTRACT -The objective of this trial was to evaluate the performance of veal calves fed whole milk or milk replacers. Thirty Holstein calves from birth up to 160-170kg of body weight were randomly allotted to the following experimental treatments: I-whole milk; II-whole milk up to 100kg of body weight, and from this weight on, the supply of more liquid diet was from a commercial finishing milk replacer, added to the milk, up to slaughter; III-whole milk up to the 10 th day of life, starter commercial milk replacer up to 100kg of body weight and finishing commercial milk replacer up to slaughter. There was no significant difference among treatments for calves daily weight gain (NS), age at slaughter (P=.06701) and carcass rate (P=0,21527); however, calves on treatment III showed higher dry matter feed intake (P=.00055) and, consequently lower feed efficiency (P=.00021). There was no significant difference among treatments for scours (P>.05) and nasal flow. The utilization of the tested milk replacer would be economically feasible if the price of 1kg of de product (powder) would be lower than 6.4 times the price of 1kg of whole milk.

The use of sexed semen in dairy cattle almost eliminates the birth of unwanted male calves and can lead to increased milk production by means of genetic selection exerted on the females. However, AI with sexed semen still presents several obstacles to overcome. Holstein-Zebu cows are responsible for 80% of the milk produced in Brazil. These crossbred animals are used extensively throughout the country because their physiologic and morphologic characteristics are compatible with milk production in the tropics which results in an economic performance advantage. The objective of this study is to evaluate the conception rates with sexed semen, comparing it to the use of non-sorted semen in crossbred dairy cows. In addition, two insemination times had been studied to determine the best timing for AI with the sexed semen. Both studies were carried out in the Experimental Station Seropedica of Pesagro-RJ, located in the state of Rio de Janeiro, Brazil. The experiment was done in 2008/2009 (January to April). In the first Trial 56 Holstein-Zebu females, composed of 1/2 to 7/8 Holstein genetics, were inseminated 12 h after estrus detection with non-sorted semen (control group n = 29, 14 heifers and 15 cows) or with sexed semen (experimental group n = 27, 13 heifers and 14 cows). The semen utilized was from the same bull and thawing was performed intravaginally. In the second trial, 55 females were inseminated only with sexed semen from the same bull, with thawing in water at 35°C, at two different times: 12 h after estrus observation (control group n = 27, 12 heifers, 4 primiparous, and 11 multiparous) and 15 h after estrus observation (experimental group n = 28, 12 heifers, 5 primiparous, and 11 multiparous). The pregnancy diagnoses were done by rectal palpation and transrectal CAT scan at Day 45. Statistical analyses had been done using Chi-square. The conception rate in the first trial was of 17.2% (5/29) for sexed semen and 53.8% (14/26) for non-sorted semen (P < 0.05). In the second trial, the conception rate was of 37.0% (10/27) for insemination with sexed semen, 12 h after estrus observation and 50.0% (14/28) for the females inseminated 15 h after estrus observation (P > 0.05). It is possible that one of the causes of fertility reduction with sexed semen is that sexed-sperm remain viable for a shorter time after the insemination. Inseminations with sexed semen done 15 h after estrus detection, which can be more synchronized with the time of ovulation, and when accompanied by closely controlling the thawing process, show results similar to those obtained with conventional semen.

This study aimed to evaluate the association between diarrhea and risk factors potentially related to diarrhea incidence, such as Cryptosporidium, Giardia, Eimeria and nematode infection, animal age, failure to transfer passive immunity, type of fertilization (artificial insemination - AI, in vitro production of embryos - IVP and natural breeding), mother (heifer/cow) and birth weight of heifer calves reared in individual outdoor hutches on a dairy farm. The database used in the present study refers to a weekly survey of a cohort of 118 heifer calves from birth to 100 days of age. A logistic generalized additive model (GAM) was fit to evaluate the functional relationship between the risk of diarrhea occurrence and birth weight. For analysis purposes, the database was divided into calves up to 30 days old and calves 31 to 100 days old. Bivariate and multivariate analyses were performed using logistic regression models via generalized estimating equations. All variables were included in the models and were removed oneby-one according to Wald statistics to obtain the final model. The relative risks (RR) and their respective 90% confidence intervals were estimated. The final model for calves up to 30 days old showed that IVP [RR=0.33 (90% CI 0.14; 0.75)] is a protective factor and that Cryptosporidium spp. infection [RR=1.95 (90% CI 1.22; 3.12)] is a risk factor. Although not statistically significant [RR=1.46 (90% CI 0.98; 2.18)], failure to transfer passive immunity increases the risk of diarrhea. The final model for calves 31 - 100 days old showed that IVP [RR=0.50 (90% IC 0.28; 0.89)] and birth weight ? 40 kg [RR=0.65 (90% CI 0.47; 0.89)] are protective factors. In this age group, Cryptosporidium spp. infection has no statistical significance [RR=1.25 (90% CI 0.95; 1.64)]. These results indicate that some of the diarrhea episodes observed in animals up to 30 days old could be explained by Cryptosporidium infection; therefore, better monitoring of these animals is recommended. Greater care in colostrum administration is suggested because animals with hypoglobulinemia are more sensitive to diarrhea occurrence. Although attention should be given to all animals with a low birth weight, special care should be given to those 31 to 100 days old.