In this study,the effects of two types of premixed materials with different combinations of trace elements on the production performance and antioxidant capacity of simmental beef cattle were examined.Fifteen healthy ...In this study,the effects of two types of premixed materials with different combinations of trace elements on the production performance and antioxidant capacity of simmental beef cattle were examined.Fifteen healthy simmental beef cattle of similar weight(approximately 330 kg),the same age(12 months),without castration,and a good physique were divided into three groups,with five beef cattle in each group.Food of Group Ⅰ beef cattle was supplemented with a commercially marketed 5% compound trace element premixture for fine beef cattle.Food of Group Ⅱ beef cattle was supplemented with a 5% compound microelement premixture for beef cattle that was designed to address local nutrient deficiencies and surpluses.In the blank control group,the beef cattle were not fed a premixture.The pretest period was 15 days,and the test period was divided into prefattening(45 days)and postfattening(45 days)stages.Body weight and body size indices were recorded at 1,2 and 3 months,and blood samples were collected regularly.In Group Ⅰ,the daily weight gain increased significantly by 15.7% compared with that of the control group.The largest daily weight gain was in Group Ⅱ,which increased by 31.6% compared with that in the control.During the test period of 90 days,the body size indices of the three different groups increased in different months,with significant increases in the indices for both test groups compared with those of the control.In Group Ⅰ,the activity of CP,the total activity of SOD and Cu-Zn-SOD increased significantly(p<0.05)compared with those in the control group,with a highly significant increase observed in GSH-PX activity(p<0.01).In Group Ⅱ,the increases in the activity of CP and the total activity of SOD and Cu-Zn-SOD were highly significant compared with those in the control group(p<0.01).In addition,a significant increase was observed in GSH-PX activity(p<0.05).Based on pretest results,the concentrations of Cu,Zn,Mo,Mn,Se and Co in the blood of experimental beef cattle were lower than those of the normal range.After feeding for 90 days,the concentrations of Cu,Zn,Mo,Mn,Se and Co in the blood of Groups Ⅰ and Ⅱ were significantly higher than those in the control group(p<0.05).The concentrations of elements in the blood of Group Ⅱ were close to the appropriate levels.Thus,the effects of the specifically designed compound microelement premixture on the prevention of nutrient imbalances and control of beef cattle nutrition metabolism and the production of fattened beef cattle were significant.展开更多
healthy periparturient cows were randomly allocated into three groups and fed 100% energy diet (NRC standard diets), 120% energy diet and 80% energy diet, respectively, beginning at 28 days prior to anticipated partur...healthy periparturient cows were randomly allocated into three groups and fed 100% energy diet (NRC standard diets), 120% energy diet and 80% energy diet, respectively, beginning at 28 days prior to anticipated parturition. After parturition, all the cows were provided with the lactation ration ad libitum until the day 56 postpartum. The objectives of the study were to investigate the effect of energy intake during the dry period on the production performance in the postpartum cows. The results indicated that the cows fed with high energy diet during the dry period had a lower dry material intake (DMI) and reduced milk production and a significant body weight (BW) loss compared with the cows fed with 80% energy diet and 100% energy diet. The results suggested that energy intake during the dry period was an important factor that influences and regulates DMI, milk production and energy equilibration of postparturient cows.展开更多
After 1500 male and female broiler chickens from a pure line were selected on the basis of plasma very low density lipoprotein (VLDL) concentration at 8 weeks of age,abdominal fat(AF),liver fat,body weight,meat traits...After 1500 male and female broiler chickens from a pure line were selected on the basis of plasma very low density lipoprotein (VLDL) concentration at 8 weeks of age,abdominal fat(AF),liver fat,body weight,meat traits and plasma lipids were determined,and effects of interaction between genotype and nutrition on AF and its correlated traits were studied.1) It was efficient to select against AF on the basis of plasma VLDL concentration.The indirect response of gizzard fat was the greatest,and that of liver fat was the second.AF was decreased,whereas liver fat was increased,feed conversion efficiency during growing period were improved, body weight and meat traits were both not influenced by selecting for low plasma VLDL concentration.2) Nutrition had significant effect on fat deposition and growth performance.Interaction between line and diet had evident effect on AF and its correlated traits.In general,diet had greater effect on H-VLDL line than L-VLDL line,namely chickens of L-VLDL line were less sensitive to diet than those of H-VLDL line.3) Due to high coefficients of variation of plasma VLDL and AF in H-VLDL and L-VLDL lines in the first generation.It will be possible that plasma VLDL is to be selected continuously to breed low fat line of broiler chickens of which the feed conversion efficiency is much better.Moreover,family combined with individual selection should be adopted during future generation selection and breeding because of significant family difference in plasma VLDL concentration.展开更多
The chickens studied were from a pure line of brown shell egg-type (YAFA) female grandparents of 17-week-old. Plasima very low density lipoprotein (VLDL) concentration was measured with turbidimetric assay. The experi...The chickens studied were from a pure line of brown shell egg-type (YAFA) female grandparents of 17-week-old. Plasima very low density lipoprotein (VLDL) concentration was measured with turbidimetric assay. The experiment results showed that the phenotypic correlations between 29-week or 50-week plasma VLDL concentration and egg production (EP) were positive in the early stage of laying period, but those in the latter stage were negative. Selection for low plasma VLDL concentration will decrease the EP in the early stage of laying period but increase the one in the latter stage. There was a significant negative phenotypic correlation between the age at first egg (AFE) and 18-week body weight (BW). The phenotypic correlation between 29-week plasma VLDL concentration and the AFE was negative. AFE was influenced by BW and body fatness as well. There was significant positive phenotypic correlation between plasima VLDL concentration and body weights (BWs) at the same stage in laying period and the phenotypic correlation was also positive between 29-week plasma VLDL concentration and the BW at middle stage of laying period, indicating that selection for low plasma VLDL concentration would reduce BWs at various stages to different degree.展开更多
基金Supported by the National Science and Technology Support Program Project(2011BAD47B04)
文摘In this study,the effects of two types of premixed materials with different combinations of trace elements on the production performance and antioxidant capacity of simmental beef cattle were examined.Fifteen healthy simmental beef cattle of similar weight(approximately 330 kg),the same age(12 months),without castration,and a good physique were divided into three groups,with five beef cattle in each group.Food of Group Ⅰ beef cattle was supplemented with a commercially marketed 5% compound trace element premixture for fine beef cattle.Food of Group Ⅱ beef cattle was supplemented with a 5% compound microelement premixture for beef cattle that was designed to address local nutrient deficiencies and surpluses.In the blank control group,the beef cattle were not fed a premixture.The pretest period was 15 days,and the test period was divided into prefattening(45 days)and postfattening(45 days)stages.Body weight and body size indices were recorded at 1,2 and 3 months,and blood samples were collected regularly.In Group Ⅰ,the daily weight gain increased significantly by 15.7% compared with that of the control group.The largest daily weight gain was in Group Ⅱ,which increased by 31.6% compared with that in the control.During the test period of 90 days,the body size indices of the three different groups increased in different months,with significant increases in the indices for both test groups compared with those of the control.In Group Ⅰ,the activity of CP,the total activity of SOD and Cu-Zn-SOD increased significantly(p<0.05)compared with those in the control group,with a highly significant increase observed in GSH-PX activity(p<0.01).In Group Ⅱ,the increases in the activity of CP and the total activity of SOD and Cu-Zn-SOD were highly significant compared with those in the control group(p<0.01).In addition,a significant increase was observed in GSH-PX activity(p<0.05).Based on pretest results,the concentrations of Cu,Zn,Mo,Mn,Se and Co in the blood of experimental beef cattle were lower than those of the normal range.After feeding for 90 days,the concentrations of Cu,Zn,Mo,Mn,Se and Co in the blood of Groups Ⅰ and Ⅱ were significantly higher than those in the control group(p<0.05).The concentrations of elements in the blood of Group Ⅱ were close to the appropriate levels.Thus,the effects of the specifically designed compound microelement premixture on the prevention of nutrient imbalances and control of beef cattle nutrition metabolism and the production of fattened beef cattle were significant.
文摘healthy periparturient cows were randomly allocated into three groups and fed 100% energy diet (NRC standard diets), 120% energy diet and 80% energy diet, respectively, beginning at 28 days prior to anticipated parturition. After parturition, all the cows were provided with the lactation ration ad libitum until the day 56 postpartum. The objectives of the study were to investigate the effect of energy intake during the dry period on the production performance in the postpartum cows. The results indicated that the cows fed with high energy diet during the dry period had a lower dry material intake (DMI) and reduced milk production and a significant body weight (BW) loss compared with the cows fed with 80% energy diet and 100% energy diet. The results suggested that energy intake during the dry period was an important factor that influences and regulates DMI, milk production and energy equilibration of postparturient cows.
文摘After 1500 male and female broiler chickens from a pure line were selected on the basis of plasma very low density lipoprotein (VLDL) concentration at 8 weeks of age,abdominal fat(AF),liver fat,body weight,meat traits and plasma lipids were determined,and effects of interaction between genotype and nutrition on AF and its correlated traits were studied.1) It was efficient to select against AF on the basis of plasma VLDL concentration.The indirect response of gizzard fat was the greatest,and that of liver fat was the second.AF was decreased,whereas liver fat was increased,feed conversion efficiency during growing period were improved, body weight and meat traits were both not influenced by selecting for low plasma VLDL concentration.2) Nutrition had significant effect on fat deposition and growth performance.Interaction between line and diet had evident effect on AF and its correlated traits.In general,diet had greater effect on H-VLDL line than L-VLDL line,namely chickens of L-VLDL line were less sensitive to diet than those of H-VLDL line.3) Due to high coefficients of variation of plasma VLDL and AF in H-VLDL and L-VLDL lines in the first generation.It will be possible that plasma VLDL is to be selected continuously to breed low fat line of broiler chickens of which the feed conversion efficiency is much better.Moreover,family combined with individual selection should be adopted during future generation selection and breeding because of significant family difference in plasma VLDL concentration.
文摘The chickens studied were from a pure line of brown shell egg-type (YAFA) female grandparents of 17-week-old. Plasima very low density lipoprotein (VLDL) concentration was measured with turbidimetric assay. The experiment results showed that the phenotypic correlations between 29-week or 50-week plasma VLDL concentration and egg production (EP) were positive in the early stage of laying period, but those in the latter stage were negative. Selection for low plasma VLDL concentration will decrease the EP in the early stage of laying period but increase the one in the latter stage. There was a significant negative phenotypic correlation between the age at first egg (AFE) and 18-week body weight (BW). The phenotypic correlation between 29-week plasma VLDL concentration and the AFE was negative. AFE was influenced by BW and body fatness as well. There was significant positive phenotypic correlation between plasima VLDL concentration and body weights (BWs) at the same stage in laying period and the phenotypic correlation was also positive between 29-week plasma VLDL concentration and the BW at middle stage of laying period, indicating that selection for low plasma VLDL concentration would reduce BWs at various stages to different degree.
