The relationship between rumination appearance, ruminal fermentation and metabolite substance concentrations of blood plasma was investigated using four rumen cannulated Suffolk crossbred adult wethers. The animals were weighing 54 kg on average. Experimental diet was chopped timothy hay, rolled barley and wheat bran in control treatment (CTL), and chopped timothy hay, starch and casein in experimental treatment (INF), respectively. In the INF, starch and casein were suspended in buffer solution and infused into the rumen of the four sheep for 4 hours. The feed was offered to the animal at 9 : 00 and 21 : 00 hours, and the chopped hay and infusate was provided to suffice maintenance requirement of metabolizable energy for each animal. Seven days of adaptation period was followed by sampling period. Eating and rumination behavior of the animals was monitored for three consecutive days. Rumen fluid samples and blood samples were obtained from each sheep at 0, 4, 8 and 12 hours post morning feeding. Osmotic pressure of rumen fluid and blood plasma and metabolites concentration of blood plasma were determined. Both of the rumination lag time post prandial and total rumination latency time between the rumination periods were significantly longer for INF than those for CTL. The number of rumination period of INF was around 50% observed in CTL. The values of rumen fluid osmolality were significantly higher for INF than for CTL throughout the observations, however, those values did not associated with the differences in blood plasma osmolality between the treatments at each sampling time. The results in this experiment suggested that a rapid fermentation of the substrates appeared to be associated with the lengthening rumination lag time, which, in turn, might contribute to enhance the absorption rate of fermentation metabolites through the rumen wall of sheep.
In this study, we investigated the Gene expressions and functions of chemerin and chemerin receptor, during adipogenesis of sheep preadipocytes. Our data showed that chemerin, chemerin receptor, adipogenic markers (PPARγ and C/EBPα) and inflammatory factor (TNF-α) gene expressions were increased at day12 after treatment with adipogenic induction medium. Furthermore, chemerin induced lipolysis in differentiated sheep adipocytes and increased sheep preadipocyte proliferation. These results demonstrate that chemerin regulates lipid metabolism and cell proliferation in sheep adipocytes. The results also suggest that chemerin may play a role homeostasis regulator in sheep adipose tissue.
The effects of different fatty acid treatments on fat accumulation and adipogenesis of sheep preadipocytes were investigated. Fat accumulation in the sheep preadipocytes was increased by differentiation induction medium treatment containing palmitic acid (100 µM). Amount of fat accumulation in sheep preadipocytes was not match the gene expressions of PPARγ and C/EBPα. Gene expression pattern of aP2 was matched the amount of fat accumulation in sheep preadipocytes. Furthermore, fatty acids treatments modulated the gene expression of some inflammation related factors. These results suggest that fatty acids are not directly involved the lipid accumulation, but regulate the inflammatory factors secretion in sheep preadipocytes.