Effects Of Starters In Different Physical Form On Performance,Rumen Fermentation And Blood Parameters In Dairy Calves

(Objective)The objective of this study was to determine whether the physical form of starter could influence performance,rumen fermentation,and blood parameters in dairy calves under hygrothermal environment.(Method)Thirty-six Holstein female calves were randomly assigned to 1 of the following 3 starter diets differing in physical forms:(1)texturized starter(TS;n=12),(2)pelleted starter with the same formula as TS(PSA;n=12),and(3)available pelleted starter(PSB;n=12).The whole experiment lasted for 63 days with a 42-d milk feeding period,a 6-d milkreducing period and a 14-d post-weaning period.All calves were fed 4 L colostrum within 1 h after birth and housed in individual hunches.They were all offered 2 L of pasteurized whole milk twice daily at 1 wk of age,3 L of milk twice daily from 2 to 6 wks of age,and 2 L of milk twice daily at 7 wks of age.Animals were weaned at the end of wk 7 and the study finished at the end of wk 9.The calves were fed starter beginning at 5 days of age.During this 9 wk study,calves had free access to water and starter.In addition,their BW was similar at the beginning of the study.(Result)The results showed as follows: 1)After being fully weaned for 2 wks,both TS and PSA had higher DMI,ADG,and gain-to-feed ratios than PSB(P>0.05).2)Calves in TS exhibited rumination behavior 4.7 days earlier than PSB and 3.8 days earlier than PSA(P<0.05).TS had a lower ammonia nitrogen content than PSA and PSB at 63 days of age(P>0.05).3)PSA had higher IgG than TS at 6 wks of age(P>0.05).4)The initial diarrhea time of PSA and TS showed 2 days later than PSB.(Conclusion)It is concluded that textured starter can promote calf performance more than pelleted starter and available pelleted starter.Twelve male calves were randomly assigned to the same three treatments for a digestion trial using iNDF digestibility and acid insoluble ash methods.The TS treatment had the lowest digestibility for CP,DM,and ADF.Hardness of corn kernels appeared to be a factor in lower TS digestibility.