Diet supplementation with clinoptilolite improves energy status, reproductive efficiency and increases milk yield in dairy heifers
The objective of this study was to investigate the effect of long-term dietary inclusion of clinoptilolite on the energy status, reproductive parameters and milk yield of dairy heifers. Eighty Holstein pregnant heifers were equally divided to two groups: treatment group heifers were fed the ration supplemented with 200 g clinoptilolite per day; control group heifers were fed the basal ration and served as controls. The experiment started on Day 210 of gestation and lasted until the end of the first lactation period. Blood samples were collected from each animal at the start of the experiment, 30 days later on the day of calving and then on a monthly basis and were analysed for serum glucose and ketone bodies. On the same days, all animals were monitored for body condition score. Cows were observed for heat every day and were inseminated at first heat after the 60th day postpartum. Calving to first heat interval, calving to first service interval, number of services per conception and calving interval were calculated for both groups. Milk yield for each cow was recorded monthly and 305-day milk yield was calculated. Clinoptilolite supplementation significantly increased body condition score and blood serum concentration of glucose and significantly decreased blood serum concentration of ketone bodies. Clinoptilolite also improved significantly the reproductive parameters evaluated and significantly increased milk production. These results indicate that daily dietary administration of 200 g of clinoptilolite can be used for the improvement of animal performance in dairy herds.