Effects Of NH₃ And H₂S On Growth Performance,Physiological And Biochemical Indexes,Immune And Antioxidant Function Of Goats

This experiment was conducted to study the effects of different concentration of ammonia and hydrogen sulfide stress on growth performance,physiological and biochemical indexes,immune and antioxidant function of goats,for evaluating the impact of harmful gas stress on the production of goats and Provide reference for the environmental control of intensive goat breeding.Eight young female goats were randomly divided into two groups,and each group had four repelicates.The test goats were in the separated,environmental controlled chamber A and B processed by the following treatments successively.Chamber A:control group（0⁶ d）,3mg·m^-33 NH₃+0 mg·m^-33 H₂S;treatment 1（T1）（8¹3 d）,20 mg·m^-33 NH₃+8 mg·m^-33 H₂S;treatment 2（T2）（15²0 d）,40 mg·m^-33 NH₃+8 mg·m^-33 H₂S;treatment 3（T3）（22²7 d）,80mg·m^-33 NH₃+8 mg·m^-33 H₂S.Chamber B:treatment 4（T4）（8¹3 d）,20 mg·m^-33 NH₃+16mg·m^-33 H₂S;treatment 5（T5）（15²0 d）,40 mg·m^-33 NH₃+16 mg·m^-33 H₂S;treatment 6（T6）（22²7 d）,80 mg·m^-33 NH₃+16 mg·m^-33 H₂S.Each treatment lasts for six days.During the experiment,fecal urine samples,whole blood samples and serum samples of goats were collected.The measured indexes include:growth performance（ADFI,ADG,F/G and ADWI）,physiology Indicators（heart rate,rectal temperature,respiratory rate,fecal urine volume,urine routine and blood routine）,biochemical indicators（serum protein,inorganic ion,glucose,urea,total cholesterol,triglyceride contents,and various enzyme activities）,immune index（Immunoglobulin,complement,lysozyme and cytokine content）and antioxidant index（T-AOC,antioxidant enzyme activity and MDA）.The results showed as follows:（1）Effects of NH₃ and H₂S stress on the growth indexes of goats.Compared with the control group,ADFI was significantly increased（P<0.05）in T1,ADG was obviously decreased（P<0.01）and F/G was significantly increased（P<0.01）in each treatment.H₂S concentration had a obvious influence on ADG and ADWI（P<0.05）.NH₃ concentration had a tendency to increase F/G.NH₃ and H₂S concentration had no significant interaction effect on growth performance.（2）Effects of NH₃ and H₂S stress on the physiological and biochemical indexes of goats.Compared with the control group,RT was obviously increased（P<0.05）at 4 days in T1,T2 and 5 days in T2;At 2 days,serum BUN content was significantly increased（P<0.05）in T3,the contents of LDH and K⁺were obviously decreased（P<0.05）in T4,RT was significantly increased（P<0.05）and the contents of LDH and K⁺were obviously decreased（P<0.05）in T5,BUN content was significantly increased（P<0.05）and LDH content was obvioustly decreased（P<0.05）in T6.At 6 days,serum LDH content was significantly decreased（P<0.05）in T5,serum LDH（P<0.05）and GLO（P<0.01）were obviously decreased in T6.H₂S concentration had a tendency to decrease the respiratory rate at 4 and 5days;in the high-concentration H₂S group,Compared with the low-concentration group,the average daily urine output（P<0.05）and serum lymphocytes（P<0.01）were significantly increased,and urinary alkalinity was obviously decreased（P<0.05）;At 2 days,the contents of serum ALB and Na⁺were increased significantly（P<0.05）,and TP（P<0.05）,GLO（P<0.05）and LDH（P<0.01）were decreased obviously;At 6 days,serum Ca²⁺content was increased significantly（P<0.05）,and the contents of LDH（P<0.05）,MCH（P<0.05）,TP（P<0.01）,GLO（P<0.01）were decreased obviously.In the 80 mg/m³ NH₃ group,serum MON content was significantly lower than that in the 40 mg/m³ NH₃ group（P<0.05）,BUN content was obviously higher than that in the 20 mg/m³ NH₃ group（P<0.05）at the same H₂S level.The contents of serum TG and Cl^-were decreased with the increase of time in climate chambers;At 6 days,serum Cl^-content was significantly decreased（P<0.05）in T1,the contents of serum TG（P<0.05）and Cl^-（P<0.01）were obviously decreased in T5,and serum TG content was significantly decreased（P<0.05）in T6,comparing with those indexes at 2days.NH₃ and H₂S concentration had a significant interaction effect on the content of serum Na⁺（P<0.05）at 2 days.（3）Effects of NH₃ and H₂S stress on the immune function of goats.Compared with the control group,serum IL-1βcontent in T3,T4 were significantly increased（P<0.05）and serum IL-6 content in T4,T6 were obviously increased（P<0.01）at 2days;contents of serum IgA,IgG（except T1）,IgM,LZM,C3 and C4 were significantly decreased（P<0.01）in other treatments and serum IL-1βcontent was obviously increased（P<0.05）in T4 at 6 days.H₂S concentration had a significant influence on goats’immunity:contents of serum LZM（P<0.05）,IL-10（P<0.05）,IL-6（P<0.01）at 2 days;contents of serum IL-1β（P<0.05）,IgG（P<0.01）,IgM（P<0.01）,IL-10（P<0.01）,C3（P<0.01）,C4（P<0.05）at 6days.With the increase of time in climate chambers,contents of serum IgG,IgM,C3,C4were decreased.NH₃ and H₂S concentration had an obvious interaction effect on contents of serum IL-1β（P<0.05）,IgG（P<0.01）,IL-6（P<0.01）at 2 days and IL-1β（P<0.05）at 6 days.（4）Effects of NH₃ and H₂S stress on the antioxidant function of goats.Compared with the control group,the activities of serum SOD（in T3,T4,T5,T6）and CAT（in T4,T5,T6）were significantly decreased（P<0.01）at 2 days;at 6 days,serum SOD,CAT in other treatments（except T1）were obviously decreased（P<0.01）,the activity of serum T-AOC in T5 was significantly decreased（P<0.05）,as well as the serum levels of MDA was obviously increased（P<0.01）in T4,T5,T6.H₂S concentration had a significant influence on goats’antioxidant function:the activities of serum GSH-Px（P<0.05）,SOD（P<0.01）,CAT（P<0.01）and MDA content（P<0.05）at 2 days;the activities of serum T-AOC（P<0.01）,SOD（P<0.01）,CAT（P<0.01）,MDA content（P<0.01）at 6 days.NH₃concentration also had an obvious influence on goats’antioxidant function:the activities of serum SOD（P<0.05）,CAT（P<0.05）at 2 days;the activities of serum SOD（P<0.01）,CAT（P<0.01）at 6 days.With the increase of time in climate chambers,the activities of serum T-AOC,SOD,CAT were decreased.NH₃ and H₂S concentration had a significant interaction effect on the activities of serum T-AOC（P<0.05）,SOD（P<0.01）,CAT（P<0.01）,GSH-Px（P<0.01）at 2 days,and the activities of serum SOD（P<0.01）,CAT（P<0.01）at 6 days.It is concluded that NH₃ and H₂S could cause stress in goats and affect the metabolism of proteins,carbohydrates and fats,destroy the serum ion balance,and reduce the growth performance,immune function and antioxidant capacity of goats.With the increase of NH₃and H₂S concentrations and the prolongation of the action time,the degree of damage to the goats became worse.