THE EFFECT OF ADDING A MIXTURE OF PROBIOTIC STRAINS TO THE FEED OF RABBITS ON THEIR HEALTH AND PERFORMANCE STATUS

Nikolay Karapetkov

Abstract: Six commercial probiotic strains (Lactobacillus delbrueckii ssp. bulgaricus NBIMCC 8244, Lactobacillus acidophilus NBIMCC 8242, Lactobacillus helveticus NBIMCC 8269, Lactobacillus delbrueckii ssp. lactis NBIMCC 8250, Streptococcus thermophilus NBIMCC 8253 and Enterococcus faecium NBIMCC 8270) were selected for a feeding trial with White New-Zealand rabbits. A study was conducted considering common farming practices in the European Union by targeting sensitive parameters in comparison to a negative control group. Characteristics like body weight (at the beginning and at the end of the trial), feed intake, mortality/morbidity and survival in the gastrointestinal (GI) tract were observed. A significantly higher bodyweight was achieved when using the probiotic mixture in the feed during the experiment with rabbits from birth to weaning at 35 days of age and from weaning to 77th day, compared with the control negative group without addition of commensals by 8.5% (P < 0.05). This body weight gain (BWG) was probably mainly a protein anabolism inducing lean meat formation and thus giving an additional benefit to farmers. The results suggest that the diversity of gut microbiota affects weight development of rabbits and that intentional manipulation of community structure may be useful for regulating energy balance in animals. The survival rates of freshly prepared cultures of the strains in simulated gastric and intestinal juice at pH 2.5 and 7 were tested and some of the strains showed good tolerance to these conditions. The use of lactobacilli probiotics, in view of the significant improvement of growth parameters in animals, should be carefully monitored, and the advantages of using these and new strains should be considered in a well-contemplated analysis.

Keywords: body weight gain; lactic acid bacteria; Probiotics; productivity; rabbits; transit tolerance

Date published: 2019-01-28