Effects of Feeding Attractants on the Growth and Body Composition,Digestive Enzyme and Serum Indices of Hucho taimen

[ Objective] The aim was to study the effects of four feeding attractants（dimethyl-15-propiothetin, trimethylamine oxide, betaine, sodium- 5＇-inosinate） on feed intake, growth performance, body composition, digestive enzyme activities and serum indices of Hucho taimen with initial body weight 9.39 ±0.26 g. [ Method] The Hucho taimen was raised in water flow system. There was one control group and four process group. Each diet was randomly assigned to triplicates of 50 fish for 56 days. During the experiment, the water temperature fluctuated from 9.3℃ to 14.2℃ and the dissolved oxygen was above 8.0 mg/L. [ Result ] The weight gain rate and specific growth rate increased significantly by adding 0.2% dimethyl- 13-propiothetin, 0.2% trimethylamine oxide, 0.2% betaine, but there were no changes with 0.05% sodium-5＇-inosinate supplementation （ P 〉 0.05）. The body crude protein increased significantly by supplementing 0.2% dimethyl-15-propiothetin（ P 〈0.05）, and body crude lipid decreased signifi- cantly by adding 0.2% trimethylamine oxide and 0.2% betaine（ P 〈0.05）, but body composition had no changes by supplementing 0.05% sodium- 5＇-inosinate（ P 〉0.05）. The digestive enzyme activities increased significantly by adding 0.2% dimethyl-13-propiothetin and 0.2% trimethylamine oxide（ P 〈0.05）, and the lipase increased significantly by supplementing 0.2% betaine（ P 〈 0.05）, but digestive enzyme activities had no changes supplemented 0.05% sodium-5＇-inosinate（ P 〉 0.05）. The serum total protein, albumin and globulin increased significantly added 0.2% dimethyl-15- propiothetin（ P 〈0.05）, and the high density lipoprotein content increased while cholesterol, triglycedde and low density lipoprotein decreased sig- nificantly added 0.2% trimethylamine oxide and 0.2% betaine（ P 〈 0.05）, and serum complement 3 and complement 4 increased significantly sup- plemented 0.05% sodium-5＇-inosinate （ P 〈 0.05）. [ Conclusion] The food intake, growth performance, body composition and digestive ability of taimen were improved supplemented with 0.2% dimethyl-15-propiothetin, 0.2% trimethylamine oxide and 0.2% betaine, respectively（ P 〈 0.05）, but not 0.05% sodium-5＇-inosinate. The immunity of body was improved by adding 0.05% sodium-5＇-inosinate.

Effect of Fruit-flavored Agent and Green Pigment on Production Performance of Simmental Cows

[Objective] The paper was to increase utilization rate of roughage to solve current shortage of forage and improve production performance of Simmental cow.[Method] Fruit-flavored agent and green pigment were added in roughage of Simmental cow respectively,and their effects on feed intake,milk production and milk quality of Simmental cow were studied.[Result] After adding fruit-flavored agent and green pigment,the feed intakes of Simmental cow were increased by 30.69% and 12.27%,while the milk productions were increased by 1.74 and 2.25 kg,respectively,and the differences were all significant（P 〈 0.05）.[Conclusion]Adding 0.3% and 0.1% fruit-flavored agent and green pigment in roughage of Simmental cow could significantly improve feed intake and milk production,which can also delay the decline of milk production during late lactation stage and improve milk quality.

Aquafeed fermentation improves dietary nutritional quality and benefits feeding behavior,meat flavor,and intestinal microbiota of Chinese mitten crab(Eriocheir sinensis)

Normally,proper fermentation can be an efficient and widely used method to improve feed quality in animal rearing;however,the studies on crustaceans,especially Eriocheir sinensis,remain limited.This study aimed to investigate whether feed fermentation could meliorate dietary nutritional value and benefit E.sinensis rearing.First,non-fermented feed(NFD)and fermented feed(FD)were produced and assessed,respectively.Then,the“Y”maze feed choice behavior test(180 times;30 times,6 rounds)was conducted to assess the attractiveness of these 2 feeds for crabs.Finally,a total of 80 crabs(44.10±0.80 g)were randomly assigned into 2 groups with 4 replicates,and fed the experimental diets for 8 weeks to evaluate the effects of each feed on growth,antioxidant capacity,meat flavor,and intestinal microbiota.In this study,FD showed higher levels of crude protein(P<0.01),soluble protein(P<0.01),amino acids(P<0.05),lactic acid(P<0.001),and lower levels of crude fiber(P<0.05)and antinutritional factors(agglutinin,trypsin inhibitor,glycinin,andβ-conglycinin)(P<0.001)than NFD.Additionally,FD was more attractive to crabs than NFD(P<0.01)and it stimulated the appetite of crabs more than NFD(P<0.05).The growth performance,feed efficiency,and digestive enzyme activity of FDfed crabs were significantly higher than those of NFD-fed crabs(P<0.05).The electronic sensory measurements and free amino acid profiles revealed that the FD diet had positive impacts on the meat flavor of crabs,particularly in“sweet”and“umami”tastes.Moreover,the antioxidant capacity of FD-fed crabs was significantly higher than that of NFD-fed crabs(P<0.05).Fermented feed also affected the diversity and composition of intestinal microflora.The functional prediction of microbial communities showed that crabs fed FD had a better microecological environment in the intestine.In conclusion,the fermentation of aquafeed could be an effective approach to enhance feed quality and therefore benefit E.sinensis rearing.