Postpartum behavioural response of Santa inês x dorper ewes and lambs in a silvopastoral system

Do forage production and ingestive behavior of locally adapted sheep differ from an irrigated silvopastoral system to an irrigated monoculture in the semi-arid region?

This study aimed to evaluate forage production and ingestive behavior of Morada Nova sheep in an intensive system with capim-tamani grass in both monoculture and silvopastoral irrigated systems in the Semi-arid region. Eighteen adult sheep, approximately 3 years old, with an average body weight of 26.8 ± 4.3 kg, were allocated to treatments with capim-tamani grass cultivated in monoculture and in silvopastoral systems with Caatinga trees. The experiment followed a completely randomized complete block design with two plots and three replications. Forage production, consumption, and behavioral activities were the assessed variables. The animals remained in the pasture daily between 6 am and 6 pm. No effects of the monoculture and silvopastoral systems were observed on the structural and productive characteristics of the capim-tamani grass pasture. There were also no observed effects on body condition score, consumption, and disappearance rate of dry matter (DM) and other nutrients in both systems. However, there was an interaction between the time animals spent under shade in monoculture and silvopastoral systems. In general, the animals spent more time under shade where there were trees, except during the period between 2 pm and 4 pm, when the times were similar. On average, the animals spent approximately 15.6% (equivalent to 1.87 h) of their total time in the artificial shade available in the monoculture system, whereas in the silvopastoral system, they remained under natural shade for approximately 40% (five and a half hours) of their time spent in the pasture during the day. The grazing frequency in both systems was approximately 70% (8.4 h) in relation to the total time spent in the pasture. The capim-tamani grass pasture managed intensively with sheep in the silvopastoral system showed similar forage production and consumption compared to the monoculture system. There was a positive influence of trees on the duration of solar radiation exposure to the animals throughout the day. The results support the need to provide shade for sheep, as well as to promote these sustainable systems in semi-arid regions.

Placental Development and Physiological Changes in Pregnant Ewes in Silvopastoral and Open Pasture Systems during the Summer

This study aimed to analyze the reproductive and physiological changes in ewes subjected to heat stress during pregnancy at UTFPR-Brazil. Twenty-four pregnant crossbred ewes were kept in a silvopastoral system (SP) or an open pasture system (OP) throughout the final trimester of pregnancy. Both systems were stressful, but the SP system had lower air temperature than the OP system (26.0 ± 0.38 and 26.9 ± 0.41 °C, respectively; p = 0.0288). Moreover, the radiant thermal load of the two groups presented a difference of 34 Wm^-2 (p = 0.0288), and the grass temperature was also lower in the SP system compared to that in the OP system (23.4 ± 0.37 and 25.6 ± 0.44 °C, respectively; p = 0.0043). The respiratory and heart rates of animals from the OP group were higher than those from the SP group (p < 0.001), but no difference was observed in the mobilization of white blood cells (p = 0.4777), and the neutrophil count was only affected by time (p < 0.0001). As regards placental biometry, placentas in twin pregnancies had a greater membrane area (p = 0.0223), but no differences between the systems were observed in placental weight (p = 0.1522) and the number of cotyledons (p = 0.5457). We concluded that the type of rearing system used affects the thermal comfort of pregnant ewes, and that an SP system can offer more amenable microclimatic conditions, which result in greater comfort for the ewes.