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Late pregnancy is accompanied by dramatic changes in the metabolism of sheep, in which the nutrient requirements increase and the metabolic capacity of ewes is under severe stress due to the rapid foetal growth and development of the mammary gland. The blood metabolic profile can be used to monitor these alterations, which can lead to metabolic disorders such as pregnancy toxaemia. However, data available on serum parameters in sheep do not consider physiological state. Therefore, the present study aimed to determine the biochemical reference ranges for pregnant ewes, including serum energy, protein and enzyme-related metabolites. Data from a variety of metabolites were obtained from experiments performed in several institutions and commercial farms using Santa Inês, Dorper, Lacaune, Morada Nova, Bergamacia and Suffolk ewes reared under different conditions (grazing, feedlot, semi-feedlot, collective and/or individual pens, and metabolic cages) from 2006 to 2017. All animals were healthy and without feed restriction. Data from ewes with any clinical manifestations were removed. The metabolic energy profile included data of glucose, cholesterol, triglyceride, high-density lipoprotein, low-density lipoprotein and very-low-density lipoprotein levels; the metabolic protein profile included the metabolites total protein, uric acid, urea, albumin, and creatinine; and the metabolic enzymatic profile included the enzymes aspartate aminotransferase, gamma-glutamyl transferase and alkaline phosphatase. The reference ranges were estimated using the software RefVal 4.11. Dixon’s test was used to identify and remove outliers. The confidence intervals and percentiles were estimated using the nonparametric method of bootstrap when data were not normally distributed. A 95% confidence level was used. The serum biochemical reference ranges for pregnant sheep determined in our study were strongly divergent from those established by one of the most cited books on the topic, especially considering the high serum urea and cholesterol concentrations and low levels of blood glucose observed. Therefore, it is essential to consider physiological status when evaluating the blood metabolic profile of pregnant ewes in order to maintain an adequate nutritional management and to prevent health disorders that may lead to productive and reproductive losses.

Context: On-animal sensing systems are being promoted as a solution to the increased demand for monitoring livestock for health and welfare. One key sensor platform, global navigation satellite system (GNSS) positioning, provides information on the location and movement of sheep. This information could be used to detect partition in sheep, a key period of time when both ewes and lambs are at risk. The development of algorithms based on key behavioural features could provide alerts to sheep managers to enable intervention when problems arise. Aims: To investigate the use of GNSS monitoring as a method for detecting behavioural changes in sheep in the period around parturition. Methods: GNSS collars were attached to 40 late gestation ewes grazing a 3.09 ha paddock in New Zealand. Several metrics were derived: (i) mean daily speed, (ii) maximum daily speed, (iii) minimum daily speed, (iv) mean daily distance to peers, and (v) spatial paddock utilisation by 95% minimum convex polygon. Speed metrics and distance to peers were also evaluated at an hourly scale for the 12 h before and 12 h after lambing. Key results: Minimum daily speed peaked on the day of parturition (P < 0.001), suggesting animals may have been expressing more agitation and did not settle. Isolation was also evident during this time, with postpartum ewes located further from their peers than pre-partum ewes (P < 0.001). Day of lambing was also evident by reduced spatial paddock utilisation (P < 0.001). Conclusions: This study demonstrates that GNSS technology can be used to detect parturition-related behaviours in sheep at a day scale; however, detection at the hour scale using GNSS is not possible. Implications: This research highlights the opportunity to develop predictive models that autonomously detect behavioural changes in ewes at parturition using GNSS. This could then be extended to identify ewes experiencing prolonged parturition, for example dystocic birth enabling intervention which would improve both production and welfare outcomes for the sheep industry. Remote monitoring of animal behaviour can improve existing methods of animal management, improving both animal welfare and productivity. This research examines the use of global navigation satellite system tracking technology to identify birth events in sheep. This provides necessary baseline data for development of behavioural algorithms for remote animal monitoring. [ABSTRACT FROM AUTHOR]

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 consumo de alimentos exerce grande influência no crescimento e desempenho dos animais visto que, será a partir da ingestão de matéria seca que ocorrerá o fornecimento da quantidade de nutrientes necessários para atender os requerimentos de mantença e de produção dos mesmos. Objetivou-se avaliar o consumo de matéria seca, crescimento corporal, ganho de peso e carcaça via ultrassonografia de cordeiros alimentados com ração extrusada em diferentes relações volumoso (V): concentrado (C). Foram utilizados 30 borregas, mestiças (Santa Inês x Dorper), com idade de três meses, e peso médio de 20 kg. Os tratamentos consistiam de ração extrusada nas relações 30V:70C e 70V:30C, com os animais distribuídos inteiramente ao acaso com dois tratamentos e 15 repetições. As médias das variáveis analisadas foram avaliadas pelo teste de Tukey e estudo de regressão para as variáveis analisadas no período ao nível de significância de 5%. Foram avaliados o consumo de matéria seca (CMS), ganho de peso, crescimento corporal através de medidas biométricas e avaliação de carcaça através de ultrassonografia. Houve redução do CMS em relação ao peso corporal ao longo do período experimental e menor CMS pelos animais no tratamento 30V:70C. Observou-se efeito quadrático para as variáveis de crescimento altura do posterior, altura do anterior, comprimento corporal, circunferência torácica e do barril, indicando que os animais apresentaram crescimento corporal adequado, com intenso desenvolvimento durante o período experimental e estabilização ao fim do experimento. Não observou-se diferença no ganho de peso dos animais, sendo o ganho médio diário de 182,79 g dia-1. Com relação a avaliação de carcaça observou-se diferença no período de avaliação, com maior área de olho de lombo, escore de condição corporal e espessura de gordura subcutânea no final do período experimental. O uso da ração extrusada com relação 30% volumoso e 70% concentrado promove melhor conversão alimentar nos animais, uma vez que alcançou o mesmo ganho de peso e desenvolvimento corporal com menor consumo de matéria seca pelos animais.

The objective of our study was to compare the intake and digestibility of dry matter and nutrients, and the nitrogen balance, of lambs fed extruded ration with different roughage (R) to concentrate (C) ratios. The experiment was carried out at the Federal University of Uberlândia (UFU), Experimental Farm Capim Branco, from 7 December 2016 to 6 January 2017. Ten lambs (Santa Inês × Dorper) aged between four and five months, and with a mean weight of 25.9 ± 2.8 kg, were used. The animals were placed in metabolic cages equipped with a feeder, drinking fountain, and salt shaker, and which had a wooden slatted floor. The treatments consisted of extruded ration with 30R:70C or 70R:30C. Treatments were distributed in a randomised, complete block design, with each treatment being performed twice and with ten replications. The experiment was carried out in two blocked stages. Differences in the means of treatments were evaluated by Tukey’s test at a significance level of 5%. Intake and digestibility of dry matter and nutrients, water intake by animals, and nitrogen balance were also analysed. The 30R:70C treatment resulted in a lower intake of dry matter, crude protein, neutral detergent fibre, acid detergent fibre and hemicellulose, and caused higher dry matter and neutral detergent fibre digestibility. The 30R:70C treatment also resulted in a lower intake and faecal excretion of nitrogen, consequently establishing a higher ratio between retained and ingested nitrogen. In conclusion, the ration with 30R:70C results in lower intake, and better utilisation of nutrients by the animal.

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.