| OBJECTIVE: Chinese Herbal Feed Additive is a new feed additive which is good for health. As we know, Heat stress does serious harm to dairy cows such as decreasing milk yield and reproduction, increasing the incidence of disease etc. Studies of Chinese Herbal Feed Additive showed this feed additive can increase milk yield of dairy cows. The following experiments were carried out in order to clarify the mechanism of Chinese Herbal Feed Additive's function of alleviating heat stress and to clarify its effect on dairy cows.METHOD: The experiments were conducted with Chinese Holstein cows during the hot months (July-August). Cows in trial group were fed rations supplemented with Chinese Herbal Feed additive at 280g/day per cow , and the control group were fed rations without additive. During the experiment, milk yield of cows in trial and control group was checked. Samples of serums and milk of cows were collected in both trial and control group before and after the experiment respectively. The endocrine levels of cortisol, T4, T3 in peripheral serum were tested by radio immunoassay; the activity of ALT, AST, ALP and CK and the level of K, Na, Cl, Ca, P in serum were tested by automatic biochemical assay; and by using milkoscan and Atomic absorption spectrometry, the level of Fat, Protein, Lactose, TS, SNF in milk and K, Na, Ca, P, Zn, Fe, Mg, Cu in milky juice were tested. All the data was analyzed by Microsoft Excel and SPSS.RESULTS: IThe milk yield of the trial group is l.OSKg /day per cow higher than the control's increased by 8.81% .2 The level of Protein, TS and SNF of milk, in the trial group after the experiment increased remarkably with a significant difference (P<0.01and P<0.05) respectively compared to those in the trial group before the experiment; Milk fat and milk protein in the trial group increased by 6.32% and 16.61% respectively compared to the control group after experiment. This Thermoresistant Stress Alleviating ofChinese Herbal Feed Additive affected the level of mineral composition of milk: After experiment, for the trial group, the level of K decreased by 8.98%, another mineral composition increased greatly, thereinto, Zn increased by 35.99% with a significant difference (P<0.05); However, the level of Cu and Fe in the control group after experiment decreased by 13.56% and 16.19% respectively, others changed little; Compared to the control group, Na, Zn, P, Ca, Fe in the trial group all increased by different degree after experiment, K and Cu decreased, and Mg changed not clearly.3 Before the experiment, the levels of cortisol and T4 in the trial group were lower than those of the control group, and the levels of ALT and CK were exactly reversed; After the experiment , the levels of cortisoK T4 , TS in the trial group increased by 24.71%, 3.25% , 27.78% respectively, and the level of ALT, AST, CK, ALP decreased by 7.10%, 2.22%, 6.57%, 34.23% respectively compared to the control group. For the trial group, the level of cortisol increased significantly (P<0.01), T3, T4 also increased by 25.78%, 30.84% respectively, the activity of ALT, AST (P<0.05) and CK decreased, and ALP increased after the experiment; However, with the development of heat stress, for the control group, the level of cortisol decreased, the activity of ALP, ALT increased, and the level of GLU, Ca, P, Na(P<0.05) all decreased; After being supplemented with this feed additive, GLU, P, Na in the trial group increased by different degree, and Ca changed from 6.67%lower than that of the control group before the experiment to 2.15% higher than that of the control after the experiment.Present Situation and Prospects of Thermoresistant Stress Alleviating of Chinese Herbal Feed Additive to Dairy Cows:Results of this trial and other scholars' show this Chinese Herbal Feed Additive can alleviate heat Stress. Besides that, Chinese Herbal Feed Additive has its own particular advantage. With the development of science technology and feed industry, in the condition of more and more people claiming to go back to nature,...
|
PDF Full Text Request