Effect of using unconventional an energy source in silage possessing on silage quality and performance of lactating cows

The aim of this study was to investigate the effect of partial substitution of corn grains with culling dates as a source of energy at making silage from corn stalk on silage quality and performance of lactating dairy cows. Sixteen crossbreeds (Balady X Friesian) lactating cows were assigned to four balanced groups and fed individually for ۹۰ days on experimental rations whereas all the groups were received a basal diet with one of four kinds of silage as follows: ۱۰۰ % GC (R۱), ۷۵ % GC + ۲۵% CD (R۲), ۵۰ % GC + ۵۰ % CD (R۳) and ۲۵ % GC + ۷۵ % CD (R۴) on gross energy-based, respectively. The NH۳ concentration slightly decreased with an increased CD level. There was a slight tendency to increase silage DM content by increasing the entry-level of CD. Silage with CD appeared identical contents of OM and ash nearly to those of the control diet. DM and OM digestibility were significantly (P<۰.۰۵) higher in the diets containing CD than in the control diet. Nevertheless, there was insignificant (P>۰.۰۵) increases in the CP, CF, ɑ-NDF, and ADF digestibility for dietary treatment T۲, T۳ and T۴ compared to T۱. Also, no significantly different (P>۰.۰۵) was found in dry matter intake among all dietary treatments. The highest yield of actual milk and ۴% fat corrected milk was recorded with T۴ (۱۰.۸۷ and ۱۰.۲۴, respectively), while the lowest values for these items were existing in T۱ (۱۰.۰۶ and ۸.۵۶, respectively) with no significant differences. Regarding milk pH value, milk protein and ash contents have the same trend with no significant (P>۰.۰۵) difference among groups. There were significant differences in the milk fat, SNF, lactose and TS percentages between T۱ (the lowest one) and each of T۲, T۳, and T۴. Using CD to ۷۵% as a source of energy alternative of corn grains in silage did not show any negative effect on silage quality, animal performance. It could be an optimal alternative to overcome the price increase of corn or shortage of markets.The aim of this study was to investigate the effect of partial substitution of corn grains with culling dates as a source of energy at making silage from corn stalk on silage quality and performance of lactating dairy cows. Sixteen crossbreeds (Balady X Friesian) lactating cows were assigned to four balanced groups and fed individually for ۹۰ days on experimental rations whereas all the groups were received a basal diet with one of four kinds of silage as follows: ۱۰۰ % GC (R۱), ۷۵ % GC + ۲۵% CD (R۲), ۵۰ % GC + ۵۰ % CD (R۳) and ۲۵ % GC + ۷۵ % CD (R۴) on gross energy-based, respectively. The NH۳ concentration slightly decreased with an increased CD level. There was a slight tendency to increase silage DM content by increasing the entry-level of CD. Silage with CD appeared identical contents of OM and ash nearly to those of the control diet. DM and OM digestibility were significantly (P<۰.۰۵) higher in the diets containing CD than in the control diet. Nevertheless, there was insignificant (P>۰.۰۵) increases in the CP, CF, ɑ-NDF, and ADF digestibility for dietary treatment T۲, T۳ and T۴ compared to T۱. Also, no significantly different (P>۰.۰۵) was found in dry matter intake among all dietary treatments. The highest yield of actual milk and ۴% fat corrected milk was recorded with T۴ (۱۰.۸۷ and ۱۰.۲۴, respectively), while the lowest values for these items were existing in T۱ (۱۰.۰۶ and ۸.۵۶, respectively) with no significant differences. Regarding milk pH value, milk protein and ash contents have the same trend with no significant (P>۰.۰۵) difference among groups. There were significant differences in the milk fat, SNF, lactose and TS percentages between T۱ (the lowest one) and each of T۲, T۳, and T۴. Using CD to ۷۵% as a source of energy alternative of corn grains in silage did not show any negative effect on silage quality, animal performance. It could be an optimal alternative to overcome the price increase of corn or shortage of markets.

کلیدواژه ها:

cull dates ، silage ، digestibility ، milk yield ، composition ، dairy cows