Effect of Probiotic Supplementation on Milk Yield in Lactating Holstein Fresien Cross Bred Cows

On farm trial was conducted on 20 lactating crossbred cows were randomly divided into two groups on the basis of milk yield (10 to 13 kg/day) and day of calving less than 60 days to see the effect of supplement probiotic on milk yield for continuous three year (2014 to 2017). Cross bred cows were fed concentrate, green and dry fodder and wheat straw in control groups and addition of 20 grams of Probiotic was given in treatment group. Experimental feeding was continued up to 90 days. The average milk production and fat percentage was significantly higher in treatment group. Milk production efficiency was also significantly higher in probiotic supplemented in comparison to control group. It was concluded that probiotic supplementation @ 20 gram per day per animal in cows significantly increase the milk production over the control group.


INTRODUCTION
Probiotics are defined as "live microorganisms that may beneficially affect the host upon ingestion by improving the balance of the intestinal micro flora" (Fuller, 1989). The concept of microbial manipulation in the gastro-intestinal tract was first appreciated by Metchnikoff who viewed the consumption of yoghurt by Bulgarian peasants as conferring a long span of life. In dairy farming, feed is the most important factor which accounts for about 60-70% of the total cost of rearing. In order to get maximum profitability, the feed must be balanced nutritionally and also be economical. The economy of feed is not only determined by the apparent cost per kg of feed but also by the cost of feed required to produce a kg of milk. Therefore, in order to achieve maximum profitability in dairy farming there is need to adopt the scientific feeding strategies for dairy animals.Probiotics like yeast culture to improve livestock productivity, and the underlying mechanisms for such improvement, have attracted increasing attention during recent years. Yeast cells are known to be a rich source of vitamins, enzymes and yeast is also observed to stimulate cellulolytic bacteria in the rumen, increase fiber digestion and flow of microbial protein from the rumen. Hence, yeast culture supplementation has been shown to improve the growth rate and feed conversion efficiency. However, the effect of dietary yeast supplementation on milk yield and milk composition is varied. In some studies, yeast culture supplementation was shown to increase milk production and milk fat percentage (Ayadet al., 2013).
Probiotics have been observed to improve the performance of crossbred cows by increasing the count of favorable micro-flora present in the rumen and by improving feed utilization by animal, respectively. Keeping this view in mind, the present investigation was proposed to explore the possible feed additive probiotic-yeast culture, which will be more beneficial and economic in order to produce profitable performance of crossbred cows. Therefore, present experiment was planned to study the effect of supplementation of probiotic on the performance of lactating crossbred cows.

II. MATERIAL AND METHODS
Twenty lactating crossbred cows were selected from villages of Mehsana District with average milk yield of 10 to 12 kg and lactation stage below sixty days. The study was conducted during winter month of November to January for 90 days after the adoption period of two weeks for consecutive three years (2014-2017). The control animal fad concentrate, green and dry fodder and wheat straw whereas experimental group fed additional 20 grams probiotic (Gausac-product from Indian Immunological Limited). The animals were kept in well-ventilated byres with access to fresh water and having separate mangers for fodder and concentrate. The animals were milked twice a day morning and evening and the concentrate (Total quantity divided into two parts) was given as each milking time. Probiotic was added and mixed in concentrate uniformly in morning and fed individually to each animal. Milk sample from each animal in both groups were collected daily and analyzed for milk production at their village cooperative dairy regularly for 90 days. All the periodicals data with regards to milk yield were statistically analyzed by paired 't' test with Systat 7.0 (1997).

III. RESULT AND DISCUSSION
Feeding of probiotic resulted in significant (P<0.05) increase in milk yield a ( Table 1). Milk yield increased by 7.6 % in probiotic fed group over the control group.

IV. CONCLUSION
On Farm Test result showed that supplementation of probiotic to high yielding crossbred cows is beneficial in terms of increasing milk yield. Further research is necessary to find out the supplemental effect of the probiotic on dairy animals fed various types of basal rations at different productive levels and stage of lactation.