Early growth, backfat thickness and body condition has major effect on early heifer pregnancy in Nellore cattle.

The aim was to evaluate the association between growth, carcass and visual scores traits with precocious calving in Nellore cattle. Birth weight (BW), weight at 120, 210, 365 and 450 days of age, pre and post-weaning average daily gain, rib eye area, backfat thickness (BF), rump fat thickness and visual scores obtained at 18 months were used for the analysis. Records from 700 females born between 2009 and 2015, exposed to mating starting at 11 months of age were analyzed. Discriminant analyzes were performed with the software Statistica. BW and BF showed the highest (P>0.01) discrimination value for early heifer pregnancy (EP). Extreme intrauterine growth retardation can result in slower growth, which reflects in the worst reproductive performance, confirmed by the variation in BW between precocious and conventional heifers. The results also demonstrate that the level of body fat affects begin of puberty. Bone structure, musculature, depth, tail insertion and rump scores presented the highest discrimination value for EP. These traits can be used as selection tools to improve sexual precocity in female Nellore cattle. The results obtained in this study would support farmers to guide the heifer management and decisions in order to enhance the EP.

High frequency of cutaneous squamous cell carcinoma in Friesian Milchschaf sheep in Uruguay / Alta frequência de carcinoma cutâneo de células escamosas em ovinos da raça Frisona Milchschaf no Uruguai

This study described five cases of squamous cell carcinoma (SCC) in the pinnae, eyelids, and eyes of Friesian Milchschaf sheep from two flocks raised under extensive conditions in Uruguay. The prevalence values for both flocks were 2.12% and 2.53%, respectively. Macroscopically, single or multiple, nodular, verrucous, or plaque-like neoplasms, with occasional ulceration and bleeding, were observed in the affected areas. Histologically, well- and moderately-differentiated SCCs were diagnosed in three and two cases, respectively. The Milchschaf breed is native of Germany, and its individuals present white non-pigmented skin with the face and legs clear of fleece, thus adapted to areas with lower solar radiation. Additionally, in the German breeding systems, animals remain indoors for long periods. The increased exposure time to higher levels of solar radiation of the Uruguayan extensive production systems may be a predisposing factor for the development of SCC in this sheep breed. In Uruguay, there is more solar radiation and the production systems provide less protection against sunlight compared with the German production system. The high frequency of SCC should be considered prior to introducing European breeds with non-pigmented skin in Uruguay and other countries of the region.(AU)

Descreveram-se carcinomas de células escamosas (CCE) nas orelhas, pálpebras e olhos em cinco ovinos da raça Frisona Milchschaf em dois rebanhos de criação extensiva no Uruguai. A prevalência nos rebanhos foi de 2,12% e 2,53%. Macroscopicamente se observaram lesões focais ou multifocais, com aumento de volume, nodulares, verrucosas ou em placas, com ocasionais ulcerações e hemorragias. Apresentavam aspecto verrucoso, por vezes com superfície ulcerada e firmes ao corte. De acordo com as características histológicas da neoplasia, as lesões foram classificadas em CCEs bem diferenciados em três casos e moderadamente diferenciados em dois casos. Esta raça é nativa da Alemanha, caracterizada pela face deslanada e pele branca despigmentada. Na Alemanha, há menores níveis de radiação solar do que no Uruguai e seu sistema de produção é mais intensivo, com permanência dos animais confinados durante longos períodos. O aumento do tempo de exposição a níveis mais elevados de radiação solar pode ser um fator predisponente para o desenvolvimento de CCEs nesta raça em sistemas extensivos de produção no Uruguai. Neste País há mais radiação solar e os sistemas produtivos fornecem menos proteção contra a luz solar, em relação ao sistema de produção alemão. A alta frequência de CEE deveria ser levada em consideração para quem decide introduzir no Uruguai e outros países da região. raças europeias com a face despigmentada.(AU)

Endocrine and metabolic factors involved in the effect of nutrition on the production of colostrum in female sheep.

We investigated the physiological relationship between diet during pregnancy and colostrum production in ewes to test the hypothesis that for ewes that are in low body condition, with low fat reserves, the food supply will be the main source of energy for colostrum synthesis. To this end, we measured the amount of colostrum accumulated by ewes under two levels of nutrition. We also measured the circulating concentrations of metabolites and hormones associated with lactogenesis (beta-hydroxybutyrate, glucose, progesterone, prolactin, cortisol, growth hormone, leptin, insulin and insulin-like growth factor-I) Ewes were either under-fed at 70 (n = 15) or well-fed at 110% (n = 10) of their daily metabolisable energy requirement during the last two months of pregnancy. Colostrum accumulation up to parturition was 168 +/-48 g for under-fed ewes and 451 +/-103 g for well-fed ewes. After birth, under-fed ewes produced less colostrum than well-fed ewes but the difference was no longer significant. The level of nutrition also influenced the plasma concentrations of hormones and metabolites related to lactogenesis. Progesterone concentrations decreased before lambing in all animals but in under-fed ewes the fall appeared to be too small to initiate the onset of colostrum production. Beta-hydroxybutyrate concentrations were higher in under-fed than in well-fed ewes, suggesting that the under-fed ewes were mobilising more adipose tissue but they still did not meet their ME requirements for colostrum production. We concluded that, in underfed ewes, there are insufficient nutrients for adequate lactation and the hormone regime is inappropriate for good udder development and colostrum synthesis.