Comparison of production parameters, gut histology, organ weights, and portion yields of broilers supplemented with Ateli plus

[摘要] ENGLISH ABSTRACT: Antibiotic growth promoters (AGP's) have been used in feed of production animals to improvetheir growth performance and disease resistance. However, there has been an increase in thepresence of antibiotic residue in animal products, as well as an increase in untreatable illnessesdue to antibiotic resistant bacteria. This led to the European Union banning the use of antibioticgrowth promoters, in production animals, in 2006. An alternative to AGP's is therefore needed inanimal feed in order to maintain performance. Plant extracts and essential oils have gainedmuch attention, due to their natural antimicrobial, antibacterial, anticoccidial and antioxidantproperties. This study tested the efficiency of Ateli plus®, an oregano plant extract basedproduct, as a replacement to AGP's on production parameters, carcass characteristics andorgan and gut health of broilers.This study consisted of five treatments fed to broilers from hatch till 33 days of age, fed in threephases; starter, grower and finisher. The treatment diets consisted of a negative control (noAGP), positive control (AGP), Ateli plus® at 1kg/ton (Ateli plus® min), Ateli plus® at 2kg/ton forweek one followed by 1kg/ton for the remainder of the period (Ateli plus® max), and AGP plusAteli plus® max (AGP plus Ateli plus® max).Results from this study show that there was no difference in performance parameters betweentreatments. The performance parameters tested included liveability, average daily gain (ADG),average weekly feed intake, average cumulative feed intake, average weekly live weight,average cumulative weight gains, feed conversion ratio (FCR), cumulative FCR and theEuropean production efficiency factor (EPEF). Broiler breast and thigh muscle pH and colour(L*, a* and b*) reading values were measured, showing a trend for improved L* colour readingvalue and ultimate pH, in broilers supplemented with Ateli plus®. This leads to an increase inwater binding capacity and tenderness, therefore resulting in an improvement in meat quality.No differences were shown for dressing percentage and portion percentages relative to carcassweight. No significant differences were seen for tibia bone Ca and P content, or tibia bone fat,moisture or ash percentages. However a significant decrease in tibia bone strength was foundin all broilers supplemented with Ateli plus® diets and the negative control diet, compared toAGP supplemented broilers. Gut morphology showed no consistent effect of treatment on villiheight or crypt depth of the duodenum, jejunum and ileum. No significant differences betweentreatments were found for organ pH or organ weights, except the gizzard, which was heavier forAteli plus® max supplemented broilers.Ateli plus® shows promise on improving meat quality characteristics of broilers, however thesignificant decrease in tibia bone strength in Ateli plus® supplemented broilers is a majorconcern and needs to be researched further. Ateli plus® acts as a good AGP replacement, asbroiler performance for the Ateli plus® supplemented broilers was maintained, and not decreased, when compared to the AGP supplemented broilers. However, the broilers fed thenegative control diet had performance parameters statistically equal to both the Ateli plus® andAGP supplemented broilers, as well as no significant differences between organ weights werefound. It can therefore be said that the broilers were raised under good management, and theiroptimal environmental conditions. Therefore conclusive effectiveness of Ateli plus® as areplacement for AGP on broiler performance cannot be reported from this study.

[发布机构] Stellenbosch University