Supplementing diets for broilers that are low in crude protein and amino acids with protease

Abstract

The study evaluated supplementation of broiler diets with a protease enzyme. Six hundred Ross 308 female broiler chicks were acquired at one day of age and randomly distributed to three treatments with five replicates of 40 chicks each. The experimental treatements consisted of i) a positive control diet with normal levels of crude protein, digestible lysine and digestible sulphur containing amino acids (PC); ii) a negative diet with reduced levels of crude protein, digestible lysine and digestible sulphur containg amino acids (NC); and iii) the NC diet augmented with Ronozyme ProAct protease at 200 mg/kg (NC+ENZY). Compared to the other diets, feeding the PC produced the highest final bodyweight (BW), bodyweight gain (BWG), and feed intake (FI) and best feed conversion ratio (FCR) over 0 - 42 days. The PC diet also produced the highest hot and cold carcass yields, ileal protein digestibility and improved the serum biochemistry parameters. Relative to the NC, the NC+ENZY diet increased BW, BWG and FI, improved FCR, increased ileal protein digestibility, hot and cold carcass yields, and the crude protein content of meat. However, it decreased serum triglyceride and very low density lipoprotein (VLDL) cholesterol levels and the crude fat content of meat of broilers. As a result, protease supplementation at the level of 200 mg/kg may not remove the detrimental effects that are caused by a 6% reduction in crude protein and digestible amino acids on performance, hot and cold carcass yields and ileal digestibility of crude protein of broilers.
 Keywords: broiler, growth performance, low crude protein diet, meat, nutrient digestibility, protease, serum biochemistry parameters

Metabolizable Energy and Amino Acid Digestibility of Soybean Meal from Different Sources for Broiler Chickens Supplemented with Protease

“…Soybean meal is considered highly digestible for poultry, but there are still possibilities to improve its nutritional value. Several studies have shown that the addition of proteolytic enzymes can maximize protein digestibility and metabolizable energy in high-performance broiler diets [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23]. Therefore, analyzing the interaction between the origin of soybean meal and the addition of exogenous enzymes is required.…”

Effects of dietary protease supplementation on behaviour, slaughter performance, meat quality and immune organ indices of broilers

“…Under coccidial infection, the dietary supplementation of protease greatly improves the body weight of broilers, alleviating the adverse effects of the disease on growth (Peek et al 2009). Broilers fed with protease show an improvement in carcass yield without alteration in fat deposition rates (Law et al 2017), and the crude protein content of meat increases (Sarica et al 2020). Xu et al (2017) reported that diets supplemented with protease had increased the breast meat yield of broilers.…”