Whereas the use of probiotics is commonplace in commercial production of improved chicken strains, little is known about the impact of these live microbial feed additives in indigenous chickens in South Africa. This study investigated the effect of a multi-strain probiotic (containing Bacillus safensis , Bacillus subtilis , Bacillus megaterium and Cupriavidus metallidurans, total bacteria number was 1.4 × 10 8 cfu/mL), administered via drinking water, on growth performance, blood parameters, and carcass and meat quality characteristics of Potchefstroom koekoek cockerels for a period of 12 weeks. A total of 140 five-week-old cockerels were randomly allocated to 4 experimental diets formulated to have similar energy and protein levels as follows: 1) negative control diet (CON; commercial chicken grower diet without both antibiotics and probiotics), 2) positive control diet (ANTIB; commercial chicken grower diet with antibiotics [0.05% Coxistac and 0.04% olaquindox] but no probiotics), 3) negative control diet plus 2.5 mL of probiotics per litre of water (PROB25) and 4) negative control with 5.0 mL of probiotics per litre of water (PROB50). There was a significant ( P < 0.05) week and diet interaction effect on average weekly feed conversion efficiency. At 9 weeks of age, cockerels in PROB50 group had higher ( P < 0.05) feed conversion efficiency than those in CON and ANTIB groups. However, 14-week-old cockerels in PROB50 group had lower ( P < 0.05) feed conversion efficiency than those in ANTIB group. Treatments had no significant ( P > 0.05) effect on overall feed intake, overall weight gain and haemato–biochemical parameters of cockerels. Gizzard and spleen weights were similar ( P > 0.05) in PROB50, CON and PROB25 groups. Cockerels in PROB50 group had shorter ( P < 0.05) small intestine than those in CON and PROB25 groups. Cockerels in PROB50 group had larger ( P < 0.05) breast weight than those in PROB25 group. Cockerels in ANTIB and PROB50 groups had greater ( P < 0.05) wing and thigh weights than those in CON and PROB25 groups. Shank weight was similar ( P > 0.05) in PROB50, CON and ANTIB groups. Meat pH measured after 24 h of slaughter was the highest ( P < 0.05) in CON and ANTIB groups followed by PROBO25 and PROB50 groups. Cockerels in CON group had lower ( P < 0.05) cooking losses than those in ANTIB, PROB25 and PROB50 groups. It was concluded that probiotics can be used in place of prophylactic antibiotics in Potchefstroom koekoek cockerels.

Use of antibiotic growth promoters in poultry production to enhance performance is not recommended due to accumulation of antibiotic residues in the end products which can confer antimicrobial resistance (AMR) to consumers. Inclusion of probiotics in layers diets has reportedly enhanced laying performance and egg quality without the risks of AMR. A study to determine the effect of supplementation of a multi-strain probiotic on performance and egg quality was carried. A multi-strain probiotic (MolaPlus®) was purchased from a reputable supplier and administered to laying birds via drinking water at different levels; Prob0(control), Prob2.5(2.5ml/L), Prob5(5ml/L), Prob10(10ml/L) and Prob15(15ml/L). The birds were fed on mash feed which was purchased from a reputable feed manufacturer. One hundred and fifty (150) 65-weeks old ISA Brown were recruited from a laying flock and assigned to the five (5) treatments. The feed intake, body weight, egg weight, egg specific gravity, yolk colour, eggshell weight, and thickness was recorded weekly for 5 weeks. Hen day egg production and water intake were recorded daily while the mineral content of the eggshells (Ca & P) was determined during the 1st, 3rd and 5th week. The mean daily feed intake, feed conversion ratio (FCR), body weight, hen day egg production, water intake, yolk colour, egg weight, specific gravity, shell weight, shell thickness and eggshell % were not influenced significantly (p > 0.05) by probiotic inclusion levels. There was a significant (p < 0.05) increase in calcium content of the shells with inclusion of probiotics with Prob5 (52.8%) being the highest. The phosphorus content of the eggshells was significantly higher (p < 0.05) for Prob5 (0.5311) and Prob15 (0.5093) compared to control (Prob0), Prob2.5 and Prob10. From the findings, it can be concluded that a multi-strain probiotic (MolaPlus®) can be included in layers diet via drinking water to improve egg quality