Effects Of Environmental Enrichment And Stocking Density, Water Temperature And Fan Ventilation On Sheep Welfare In Summer On Sheep Welfare

Four trails were conducted to evaluate the effects of environmental enrichment, stocking density; water temperature and fan ventilation on sheep welfare.Twenty four thin-tailed Han sheep were assigned to three treatments. :1) confinement in a pen (A); 2) confinement in a pen with a yard (B); 3) confinement in a pen with a yard and environmental enrichment as well (C). The results showed that environmental enrichment and stocking density had no significant effects on growth performance (P>0.05), although they tended to improve it. A highly significant difference in surface cleanness existed among groups (P <0.01). At Day 7, the insulin concentration in groups B and C was significantly lower than that in group A (P<0.01)). At Day 37, environmental enrichment and high stocking density significantly decreased the serum cortisol concentration (P<0.05), but had no significant effects on the other biochemical indexes. Environmental enrichment and high stocking density significantly increased walking time and significantly decreased lying and fighting time (P<0.05).Nine sheep were slaughtered at day 60. The results showed that environmental enrichment and high stocking density did not affect meat yield and meat quality (P>0.05), they had no significant effects on the content of amino acids in the longissimus muscle, either (P>0.05). Environmental enrichment and high stocking density increased the content of C20:0 and C20:2 fatty acids with no significant effects on the other fatty acids.Trial 4 was designed to study the effects of chilled drinking water and fan ventilation on growth performance, serum cortisol concentrations, behavior, duration of movement, and physiological parameters of sheep in summer. Thirty six thin-tailed Han sheep were assigned to four treatments (three replicates per treatment and three sheep per replicate) : Solar radiation with drinking water temperature of 35±3.5℃(A); Drinking water temperature of 25±0.5℃(B); Drinking water temperature of 15±0.5℃(C); Fan ventilation (wind speed 3.5 m/s) with drinking water temperature of 10±0.5℃(D). The results showed that chilled drinking water and fan ventilation had no significant effects on growth performance (P >0.05). At Day 30, the serum cortisol concentration was significantly lower in group D than that in groups A and B (P<0.05).The duration of movement was significantly longer in groups C and D than that in groups A and B (P<0.05).At the fourth week, the rectal temperature of the animals from group A was significantly higher than those from the groups (P<0.05). The respiratory rate in group D was significantly lower than those from the other groups (P<0.01). Chilled drinking water and fan ventilation increased lying time significantly(P<0.05)and decreased pluming time and idling time . Chilled drinking water and fan ventilation had highly significant effects on drinking time (P<0.01).The results indicated that providing chilled drinking water and fan ventilation improved sheep welfare in summer.Trail 5 was aimed to study the effects of drinking water temperature on sheep in summer. Thirty six thin-tailed Han sheep were assigned to four treatment (three replicates per treatment and three sheep per replicate) : Solar radiation with drinking water tem of 35±3.5℃(A); Drinking water temperature of 25±0.5℃(B); Drinking water temperature of 15±0.5℃(C); Drinking water temperature of 10±0.5℃(D). The results showed that environmental temperature and water temperature had significant effects on water consumption (P<0.05). The water consumption fluctuated within a narrow range during hot climate and chilling of drinking water to 10±0.5℃, significantly decreased water consumption in summer (P<0.05).In conclusion, environmental enrichment and high stocking density, drinking water and fan ventilation can improve sheep welfare.