Abstract

Backround:
Mastitis in dairy cows and neonatal calf diarrhea are two major health problems in the livestock industry, leading to massive economic losses while reducing animal welfare. Alternative prevention strategies are of high importance in reducing the need of conventional antibiotic-based treatments.

Aim:
In the present study, we aimed to assess dietary supplementation with Leuconostoc mesenteroides for managing mastitis and diarrhea in neonatal calves and dairy cows/.

Methods:
Calves (24 per group) and cows (50 control group and 124 probiotic group) were provided with identical feed, and the probiotic (10^4 cfu/gr) was added in the experimental group only for 90 days.

Results:
Results showed no significant effect of L. mesenteroides on average daily gain (ADG) in calves (P=0.28); nevertheless, a significant reduction was observed in fecal harmful microbial scores and diarrhea incidence (P=0.012) compared to the control group. In cows, probiotic supplementation did not significantly alter milk yield (P=0.44) or bacterial presence (P=0.68) in milk samples. Although a numerical increase in mastitis cases was noted, it was not statistically significant (P=0.17).

Conclusion:
In conclusion, under the conditions of this study, dietary supplementation with L. mesenteroides at 10^4 cfu/gr for 90 days significantly reduced diarrhea incidence in neonatal calves but had no significant effect on their growth, nor on the milk yield or mastitis rates of dairy cows

Key words: Milk production; Antibiotic-based treatment alternatives; Average daily gain; Holstein calves; Probiotics.