Impacts of protein supplementation during late gestation of beef cows on maternal skeletal muscle and liver tissues metabolism.

Since nutritional requirements are increased at the end of gestation to meet the demands of the pregnant uterus, pregnant beef cows are susceptible to mobilization of body reserves (mainly fat and amino acids (AAs)) and to alter the metabolism of nutrients in the liver and muscle to support such demands. The objective of this study was to evaluate the effect of CP supplementation on maternal nutrient metabolism in the late gestation of beef cows grazing a low-quality pasture. Forty-three pregnant Nellore cows gestating male fetuses (average age = 6 years; average weight = 544 kg) at 193 ± 30 (mean ± SD) days (d) of gestation were divided into eight groups (experimental units, with four to five cows each). Treatments were (1) control (CON, n = 4): pasture-based (PB) diet without CP supplementation and (2) supplemented (SUP, n = 4): PB diet daily supplemented with 2 g/kg of BW of a 43.5% CP supplement. Liver and skeletal muscle biopsies were performed at 265 days of gestation and samples were collected for mRNA expression. On day 280 of gestation, blood samples were collected to assess plasma levels of AA. The CON-fed cows tended to have greater (P = 0.057) total circulating AA than SUP-fed cows. The circulating glycogenic AA was greater (P = 0.035) in CON than in SUP cows. CON cows was greater for histidine (P = 0.015), methionine (P = 0.007) and alanine (P = 0.036) than SUP cows. The CON- and SUP-fed showed no differences for gluconeogenesis, fatty acid transport and signaling axis markers in the liver. The mRNA expression of markers for skeletal muscle synthesis, p7056k (P = 0.060) and GSK3B (P = 0.096), tended to be greater in cows from CON than SUP group. No differences were found for mRNA expression of markers for skeletal muscle degradation. We conclude that CP supplementation to CP-restricted late-pregnant beef cows reduces the maternal tissue mobilization and changes the profile of plasma circulating AA and the mRNA expression of markers for the synthesis of skeletal muscle tissue.

Effects of raw milk and starter feed on intake and body composition of Holstein × Gyr male calves up to 64 days of age.

The objective was to evaluate the effect of supplying different levels of raw milk, alone or in combination, with access to a starter feed, on the intake, digestibility, daily gain, N balance, and body composition of Holstein × Gyr crossbred suckling calves until 64 d of age. Thirty-nine male calves aged 4 d with an average initial live weight of 36 ± 1.0 kg were used. Five calves were defined as a reference group and slaughtered at 4 d of age to estimate the initial body composition of the animals. The other calves were distributed according to a completely randomized design in a 3 × 2 factorial arrangement consisting of 3 levels of milk (2, 4, or 8 L/d) and 2 levels of starter feed (presence or absence in diet). At 15 and 45 d of age, 4 animals from each treatment were subjected to digestibility trials with total collection of feces and urine and sampling of feeds. At 64 d of age, all animals were slaughtered and their body tissues were sampled for analyses. Total dry matter and nutrient intake increased linearly and starter intake decreased linearly in response to the supply of increasing amounts of milk. The digestibility coefficient of organic matter was not affected by the inclusion of starter feed and increased linearly as milk supply was elevated. Daily gain was greater at increased milk supply levels and also greater when starter was supplied, without any interaction between milk supply level and the presence or absence of starter. Fecal N excretion and N retention were higher in the animals fed starter feed. Fecal N excretion was not affected by milk levels, whereas N retention was affected. Body protein and ash contents decreased linearly according to increased milk allowance. In contrast, fat body content increased linearly according to milk supply. The presence of starter feed in the diet was responsible for the increased body fat content, but had no effect on protein or ash content. In conclusion, weight gain and N retention in calves up to 64 d of age increased with milk supply. Ad libitum access to starter further increased weight gain and N retention and no interaction with milk allowance level occurred. However, greater levels of milk are also associated with reduced starter feed intake, in addition to increased body fat content.

Aspectos do uso territorial por onça parda (Puma concolor), através de monitoramento via satélite, na região do Parque Estadual da Serra do Brigadeiro, MG / Aspects of territorial use of the Cougar (Puma concolor), by satelite monitoring, in the Parque Estadual da Serra do Brigadeiro, MG

Objetivou-se com o presente estudo monitorar o comportamento do uso territorial de um macho de onça parda, capturado no Parque Estadual da Serra do Brigadeiro (PESB), por meio da telemetria, usando colar de GPS via Satélite Globalstar. O monitoramento de doze meses resultou na transmissão via satélite de 328 localizações, as quais sugerem que a área utilizada por esse felino seja de aproximadamente 610km2, sendo esta a maior área já descrita para a espécie. Foi possível observar que apenas 20% das localizações ocorreram dentro da área do PESB. O comportamento territorial observado neste trabalho mostra a vulnerabilidade do animal a ações antrópicas, como a caça, atropelamentos e o contato com patógenos entre animais silvestres e domésticos. Observou-se também que duas rodovias configuram barreiras artificiais para o deslocamento do animal, possivelmente impedindo o fluxo gênico entre o PESB e dois outros importantes parques. Com os dados levantados é possível a sugestão de ações de manejo, como a criação de uma conectividade efetiva entre o PESB, o Parque Estadual do Rio Doce e o Parque Nacional do Caparaó, o que poderia contribuir para o intercâmbio genético entre as populações e, dessa forma, favorecer a conservação não somente da onça parda.

We aimed to study the territorial behavior of a male cougar, captured in the Parque Estadual da Serra do Brigadeiro (PESB), using a GPS collar and the Globalstar Satellite. Monitoring the animal for nine months we obtained 328 locations. The data suggest that the area used by this feline is approximately 610km2, the largest area described for this specie. It was also possible to observe that only 20% of the locations of the animal occurred within the PESB area. The territorial behavior observed in this study shows the vulnerability of the animal to human activities such as hunting, road kill and contact with pathogens from domestic animals. It was also observed that two roads constitute artificial barriers for animal movement, possibly preventing gene flow between the PESB and two other parks. The creation of an effective connectivity between the PESB, the Parque Estadual do Rio Doce and the Parque Nacional do Caparaó is critical to ensure genetic exchange between the animal populations and thereby promote their conservation.