The study aimed to determine the biochemical reference ranges for lambs from birth to 1 year of age in the tropics. Data were obtained from experiments performed in several institutions and commercial farms using Santa Inês, Dorper, Lacaune, Morada Nova, Bergamacia and Suffolk lambs reared under different conditions (grazing, feedlot, semi-feedlot) from 2006 to 2017. Serum energy-, protein-, mineral-, and enzyme-related metabolites were evaluated. The metabolic energy profile included data from glucose, cholesterol, triglycerides, fructosamine, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and very-low-density lipoprotein cholesterol; the metabolic protein profile included total protein, uric acid, urea, albumin, and creatinine; the metabolic mineral profile included data on calcium, phosphorus, and magnesium; and the metabolic enzymatic profile included the enzymes aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase, and creatine kinase. The reference ranges were estimated using confidence intervals with a 95% confidence level, and percentiles were estimated or bootstrapped nonparametrically when the data were not normally distributed. The serum biochemical reference ranges determined for lambs are 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, the serum biochemical reference ranges for lambs from birth to 1 year of age in the tropics differ from international data, which consider adult sheep in temperate climate zones.

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.

O trabalho teve como objetivo definir intervalos de referência para valores de metabólitos energéticos, proteicos e enzimáticos em ovinos. Os dados utilizados foram oriundos de vários experimentos realizados entre 2006 e 2018, em diversas instituições de ensino superior e pesquisa. Foi utilizado banco de dados diversificado com observações de ovinos de diferentes raças, genótipos, idades e categorias fisiológicas, criados em diferentes sistemas de manejo. Todos os animais utilizados eram saudáveis e dados de animais que apresentaram quaisquer manifestações clínicas foram descartados. Para determinar o perfil metabólico energético foram obtidos dados de glicose, colesterol, triglicerídeos, frutosamina, HDL (lipoproteína de alta densidade), LDL (lipoproteína de baixa densidade) e VLDL (lipoproteína de muito baixa densidade); para o perfil proteico, dados de proteínas totais, ácido úrico, ureia, albumina e creatinina; e para o enzimático, dados de AST (aspartato aminotransferase), GGT (gama glutamil transferase) e FA (fosfatase alcalina). As análises laboratoriais foram realizadas nos aparelhos Analisador bioquímico semiautomático modelo BIO - 2000 da marca Bioplus© e Analisador automático de bioquímica modelo PKL-125 da marca MHLab®. Para a estimativa e determinação dos valores de referência, foi utilizado programa RefVal 4.11, sendo os valores outliers removidos da avaliação. Após a determinação dos valores de referência comparou-se os dados obtidos com tabelas internacionais estabelecidas na literatura, sendo possível observar que os intervalos encontrados neste trabalho foram mais amplos, abrangendo melhor resultados obtidos em experimentos realizados no Brasil.

Objetivo-se avaliar o efeito diferente de tamanhos de partículas do volumoso e a frequência de alimentação sobre o metabolismo dos animais. Oito carneiros com peso vivo médio de 52,5kg foram distribuídos em esquema fatorial 2x4, de modo a corresponder a duas frequências de alimentação e quatro tamanhos (2mm; 5mm; 10mm e 25mm), em delineamento em blocos ao acaso. Foi utilizado o feno de Tifton-85 (Cynodon spp.) como volumoso e concentrado comercial, o que impôs um ajuste na relação volumoso:concentrado, que assim ficou quantificada: 25:75%. O trabalho de respirometria foi conduzido em câmara respirométrica, tipo circuito aberto, para pequenos ruminantes. Foram determinados os teores de oxigênio, gás carbônico e metano. Na urina, foi determinado o teor de nitrogênio. A partir desses parâmetros, foi determinada a produção de calor (PC). O nitrogênio retido representou 36,0% do Nitrogênio (N) ingerido (g/dia) e 46,8% do N absorvido (g/dia). A produção média de CH4 foi de 1,45L/UTM/dia. A PC foi cerca de 40,0% da energia bruta ingerida. A energia metabolizável foi 73,2% da Energia bruta ingerida e a energia líquida apresentou valor médio de 1.807,35kcal/dia. Não houve efeito dos tamanhos de partícula e da frequência sobre o balanço de nitrogênio e o metabolismo energético.

The objective of this study was to evaluate the use of extrused roughage on nutritional and metabolic parameters in sheep. Eighteen 3-year-old sheep in metabolic cages were randomly assigned to two treatments: corn silage and extruded roughage. Dry matter intake (DMI) and water intake were calculated as the difference between offered feed and orts left. Ruminal movement was assessed through auscultation of the rumen for five minutes, glycemia and other metabolites through blood collection by jugular venipuncture, and feeding behavior by observation every 5 minutes for 24 hours. DMI per animal, both as a percentage of live weight and in relation to metabolic weight, was higher for animals fed extrused roughage. The extrused roughage treatment also resulted in reduced ruminal movement and higher dry matter digestibility (DMD), glycemia and drinking water intake. Animals fed with extrused roughage reduced the time of rumination and total chewing, thus increasing ingestion, chewing and rumination efficiency. Blood concentrations of glucose and urea were higher in animals fed extrused roughage, while cholesterol concentration was lower. We conclude that the use of extrused roughage promotes improvement in the nutritional parameters of sheep by increasing DMI and DMD, and reducing chewing and rumination times, without causing disorders in energy and protein metabolism.