In situ, in vitro and in vivo nutritive value assessment of Barberry leaf as a roughage for goat feeding

•In situ, in vitro and in vivo investigations showed Berberis vulraris leaf (BVL) can use as an alternative forage in diet of goats.•BVL inclusion in diet affects neither lactating performance nor milk composition with exception of milk fat.•BVL inclusion in diet improved total antioxidant capacity of blood.•BVL can be used up to 34% of diet as an antioxidant rich feedstuff in feeding of goats.

This study was carried out to evaluate nutritive value of Berberis vulgaris leaf (BVL) by in situ and in vitro experiments and to investigate the effects of replacing alfalfa hay with BVL on performance, milk composition, blood metabolites and antioxidant capacity of lactating crossbred goats. Rumen dry matter (DM) degradability of BVL was assessed using two fistulated mature goats and incubation of BVL samples at specified times in the rumen. Modified 3-step procedure (TSP) was performed for determination of post-rumen DM digestibility. For the in vivo experiment (during six weeks), 21 lactating crossbred goats (55 ± 15 DIM and 26 ± 2.8 kg BW) were randomly allocated to one of three dietary treatments of BVL at levels of 0, 17 and 34% of DM. The results of in situ and in vitro experiments indicated that rumen DM degradability, post-rumen digestibility of DM undigested in the rumen and total tract DM digestibility of BVL were 65.46%, 12.84% and 69.90%, respectively. In vivo results revealed that DMI increased (P < 0.05) as BVL level in the diet raised. Also, milk fat increased (P < 0.05) with increasing BVL level in the diets, but milk protein, SNF and lactose content were not affected by the diets (P > 0.05). Goats fed BVL showed greater antioxidant capacity than goats fed control diet (P < 0.05) and no significant difference was found in plasma malondialdehyde (MDA) content (P > 0.05). Results of this study revealed that BVL has high nutritional value and might be utilised in diet of lactating goats as an inexpensive alternative roughage.