Use of probiotics containing lactobacteria to improve the microclimate and foot health of broilers

Promoting animal welfare is a very important topic in agriculture, especially in production conditions. Current issues in poultry farming are animal density, litter and air quality, which have a direct impact on birds' health and productivity. The aim of the study was to determine the effect of the application of the probiotic Lactobacillus farciminis CNCM-I-3699 and Lactobacillus rhamnosus CNCM-I-3698 complex (on feed and on litter) on air (ammonia content) and litter quality (volume and humidity) to improve broiler well-being and foot health.
In a trial 260 one day old Ross 308 broiler chicks were randomly divided in two groups – the control group (Con) n=130 and the probiotic group (ProX) n=130. The birds were placed in closed and ventilated identical pens with full microclimate control and ammonia content monitoring. 20 kg of wood shavings with 15% moisture were used for bedding. At the probiotic group the mixture of lactobacteria was manually spread 10g/m2 before the chickens were placed, and it was spread manually once a week on the litter, each time 5g/m2. Bird density, housing and microclimatic conditions were assimilated to production conditions. The amount of water consumed was measured for each group. The dietary
treatments was basal diet for the Con group and basal diet + the mixture of lactobacteria 4g/10kg for the ProX group. Broilers were raised till day 35. Litter weight and moisture was determined for each group at the beginning and end of the study. The health status of broiler foot pads was graded in scale from 1 to 3 (0 - no lesions, 1 - superficial lesions, 2 - lesions of the upper layers of the skin, 3 - lesions of the deepest layers of the skin). The total weight of bedding in the control group reached 157.5 kg, but in the probiotics group 154 kg at the end of the study, which is 2.3% less than in the control group. The moisture content of the litter in the free zone and in the feed zone was similar, ProX 41.4%, 28.3% and Con 40.4%, 26.9%, respectively. The wettest bedding was observed below the water lines, where the moisture of the Con group bedding reached 53.6%, but the ProX group bedding was 11.6% drier, respectively 42%. When analyzing the amount of NH3 in the exhaust air, the average rank was calculated, accordingly for the ProX group it was 1362.59 and for the Con group 1596.41, which did not differ significantly in the interpretation of the effect size (r = 0.11). The study found that there was no significant difference in the scores of the birds feet between the groups (p> 0.05), however, the control group with scores 3 had
more foot damage. Although there was not a significant difference in foot health between the groups, the probiotics group had lower litter moisture below the water lines, the total litter size was reduced, and the average ammonia rank was lower compared to the control group. In industrial production, this difference could be more substantial and improve the welfare of birds in general.