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Bovine cysticercosis is a problem distributed worldwide that result in economic losses mainly due to the condemnation of infected carcasses. One of the difficulties in applying control measures is the identification of the source of infection, especially because cattle are typically acquired from multiple farms. Here, we tested the utility of an animal movement network constructed with data from a farm that acquires cattle from several other different farms to map the major contributors of cysticercosis propagation. Additionally, based on the results of the network analysis, we deployed a sanitary management and drug treatment scheme to decrease cysticercosis' occurrence in the farm. Six farms that had commercial trades were identified by the animal movement network and characterized as the main contributors to the occurrence of cysticercosis in the studied farm. The identification of farms with a putative risk of Taenia saginata infection using the animal movement network along with the proper sanitary management and drug treatment resulted in a gradual decrease in cysticercosis prevalence, from 25% in 2010 to 3.7% in 2011 and 1.8% in 2012. These results suggest that the animal movement network can contribute towards controlling bovine cysticercosis, thus minimizing economic losses and preventing human taeniasis.(AU)

A cisticercose bovina é um problema distribuído mundialmente e que resulta em perdas econômicas, principalmente devido à condenação de carcaças infectadas. Uma das dificuldades em se controlar esta zoonose no Brasil é a prática de aquisição de bovinos de múltiplas fazendas, tornando quase impossível a identificação da fazenda de origem do gado infectado, onde as medidas de controle devem ser aplicadas. Objetivou-se avaliar uma rede de movimentação animal construída com dados de uma fazenda de gado de corte que adquire animais de diferentes locais, com o objetivo de mapear as fazendas que mais contribuíam para a propagação da cisticercose. Adicionalmente, com base na análise da rede de movimentação, manejo sanitário e protocolo de tratamento adequados foram aplicados para diminuir a ocorrência de cisticercose na fazenda em estudo. Seis propriedades que tinham trocas comerciais foram identificadas pela rede de movimentação de bovinos e caracterizadas como as principais contribuintes para a ocorrência da cisticercose na fazenda em estudo. A identificação de fazendas com risco de infecção por Taenia saginata por meio da rede de movimentação animal juntamente com o manejo sanitário e protocolo de tratamento adequados resultaram em diminuição gradual da prevalência da cisticercose de 25%, em 2010, para 3,7% em 2011 e 1,8% em 2012. Estes resultados sugerem que a estratégia de análise da rede de movimentação do gado, associadas ao manejo sanitário e tratamento adequados podem contribuir para o controle da cisticercose bovina, minimizando assim as perdas econômicas e prevenindo a teníase humana.(AU)

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The reproductive performance of bulls has a high impact on the beef cattle industry. Scrotal circumference (SC) is the most recorded reproductive trait in beef herds, and is used as a major selection criterion to improve precocity and fertility. The characterization of genomic regions affecting SC can contribute to the identification of diagnostic markers for reproductive performance and uncover molecular mechanisms underlying complex aspects of bovine reproductive biology. In this paper, we report a genome-wide scan for chromosome segments explaining differences in SC, using data of 861 Nellore bulls (Bos indicus) genotyped for over 777,000 single nucleotide polymorphisms. Loci that excel from the genome background were identified on chromosomes 4, 6, 7, 10, 14, 18 and 21. The majority of these regions were previously found to be associated with reproductive and body size traits in cattle. The signal on chromosome 14 replicates the pleiotropic quantitative trait locus encompassing PLAG1 that affects male fertility in cattle and stature in several species. Based on intensive literature mining, SP4, MAGEL2, SH3RF2, PDE5A and SNAI2 are proposed as novel candidate genes for SC, as they affect growth and testicular size in other animal models. These findings contribute to linking reproductive phenotypes to gene functions, and may offer new insights on the molecular biology of male fertility.

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