Studies On The Effect Of Traditional Chinese Medicine Prescriptions On Alleviating Heat Stress In Hailan Brown Laying Hens

Heat stress leads to a decline in poultry production performance and cause metabolic disorders and oxidative damage.In severe cases,it can lead to death and affect breeding efficiency.The use of traditional Chinese medicine has great potential to alleviate heat stress.In this experiment,we improved the traditional formula by combining 10 traditional Chinese medicines such as gypsum and coptis,and studied their effects on alleviating heat stress hazards in Hailan brown laying hens,both alone and in combination with vitamin C.In this experiment,90 Hailan brown laying hens were randomly divided into 3groups,with 3 replicates in each group and 10 chickens in each replicate.The negative control data group consisted of three experimental groups:group I was fed a normal diet,group Ⅱ was fed a diet supplemented with 1%traditional Chinese medicine,and group Ⅲ was fed a diet supplemented with 1%traditional Chinese medicine,and a concentration of 100 mg/kg of vitamin C was added through drinking water.The experimental period is 28 days,including a 14 day early feeding period（at room temperature）and a 14 day high-temperature treatment period.The experiment was conducted in the high-temperature control room of the experimental chicken farm at Huazhong Agricultural University.The temperature and humidity of the high-temperature experiment were set at 36±1℃,65±5%RH,and the temperature was heated for 6 hours per day（11:00-17:00）;The room temperature experiment temperature is controlled between 18-22℃.By analyzing the changes in rectal temperature,egg production performance,and blood gas and blood biochemical indicators before and after heat stress in different experimental groups,and observing the organic changes in liver,kidney,spleen and other tissue sections,the effect and mechanism of traditional Chinese medicine prescriptions in alleviating heat stress in laying hens were studied.The following are the main results and conclusions obtained:1.Rectal temperature and respiratory rate increased significantly after heat stress（P<0.01）.The comparison between different experimental groups shows that the rectal temperature and respiratory rate of group Ⅱ and group Ⅲ of Chinese herbal formula with Vc Ⅲ are significantly lower than those of group I of heat stress control,and the difference is most significant 1 day after heat stress,indicating that the addition of Chinese herbal formula with Vc can reduce the rectal temperature and respiratory rate of Hailan brown layers after heat stress,and the effect is better during acute heat stress,Compared to feeding traditional Chinese medicine alone,the combination of Vc did not show better results.2.Under the influence of heat stress,there is a significant decrease in egg production rate and egg quality（egg weight,protein height,etc.）to varying degrees.The Chinese herbal formula group Ⅱ and the combination of the formula with the Vc Ⅲ group showed no significant relief effect on the decrease in egg production rate;However,compared to the control group I,the effect of reducing egg weight and yolk color in group Ⅱ after heat stress was significant（P<0.05）;The effect of Group Ⅲ on alleviating egg weight,protein height,and decrease in Hastelloy units was significant,and the above significant differences were mainly observed in the data 1 and 4 days after heat stress.Therefore,the combination of traditional Chinese medicine has a significant alleviating effect on the decrease in egg quality during acute heat stress,but the alleviating effect on the decrease in egg production rate is not significant;Compared to feeding traditional Chinese medicine alone,the combination of Vc did not show better results.3.After heat stress,the levels of Na⁺,HCO₃^-,TCO₂,GLU and PCO₂in the blood decreased significantly（P<0.01）,while the levels of ALB,TCHO,TG,and TP in the blood decreased significantly（P<0.05）.The levels of AST,CK,LDH,Hct,Angap,and Hb in the blood increased significantly（P<0.01）,and the blood p H increased significantly（P<0.05）.Comparing different experimental groups,it was found that the blood levels of six indicators such as HCO₃^-,Cl-,and TG in Group Ⅱ of the Chinese herbal formula were significantly higher than those in Group I（P<0.05）,while the levels of CK,LDH,AST,and p H were significantly lower than those in Group I;The content of TG,Cl^-,HCO₃^-in the blood of the Chinese herbal formula combined with Vc Ⅲ group was significantly higher than that of the I group,while the content of CK and LDH was extremely significantly lower than that of the I group.Moreover,the traditional Chinese medicine formula had a significant effect on alleviating the imbalance of blood biochemical and blood gas indicators caused by heat stress during the 14 day high-temperature experiment period.The effect of reducing oxidative damage and improving nutritional status was better on the first day.The combination of traditional Chinese medicine can reduce the oxidative damage and improve the nutritional status of Hailan brown laying hens after heat stress for a long time.The effect of using traditional Chinese medicine alone to alleviate these heat stress indicators is better than using it in combination with Vc.4.The Chinese herbal formula group Ⅱ has a significant effect on improving the liver morp Hology of laying hens after heat stress,with a certain effect on the kidneys,but no significant effect on the spleen;The combination of traditional Chinese medicine formula and Vc Ⅲ group alleviated the morp Hological changes of the main organs caused by heat stress,with the opposite results.It had a better effect on the spleen,a certain effect on the kidneys,and no significant effect on the liver.The results of this experiment indicate that the combination of traditional Chinese medicine formulas with Vc has no significant advantage compared to feeding traditional Chinese medicine formulas alone;By alleviating the rapid increase of blood anion concentration and blood CO₂concentration after heat stress,the Chinese herbal formula can improve the oxidative damage caused by heat stress and protect the liver.It has a significant effect on alleviating heat stress,especially acute heat stress（reducing rectal temperature and respiratory rate after heat stress）,and helps the body enter the p Hysiological adaptation period after long-term heat stress.