Effects of Low-Protein Diets and Exogenous Protease on Growth Performance, Carcass Traits, Intestinal Morphology, Cecal Volatile Fatty Acids and Serum Parameters in Broilers

Abstract

Dietary exogenous proteases (ENZ) can be used in poultry production to improve the growth of chickens fed low-protein (LP) diets. We hypothesized that ENZ supplemented in an LP diet would improve growth performance and physiological response in broilers for 8–35 days. To investigate this, we used a 2 × 2 factorial design with crude protein (CP, normal diet (NP) and LP) and ENZ. The LP diet contained low in 1% CP and ca. 8–12% amino acids compared to the NP diet and both NP and LP diets were added without or with (1 g/kg of diet) ENZ. We randomly allocated 720 1-week-old Ross 308 male chicks to 48 pens and experimental diets. At 21 days, dietary ENZ, but not CP, increased (p = 0.007) live body weight. Body weight gain from 8–21 days was affected (p = 0.006) by dietary ENZ, but was not affected (p = 0.210) by CP. The feed conversion ratio was affected by both CP and ENZ during the starter period (p < 0.05), by ENZ (p = 0.034) during the finisher period, and by CP (p < 0.001) during the whole period. However, the interaction between CP and ENZ did not significantly affect growth performance (p > 0.05). Dietary ENZ increased (p = 0.013) the relative weight of liver at 21 days. CP and ENZ affected (p = 0.043) total short-chain fatty acids at 21 days. However, this effect was not seen (p = 0.888) at 35 days. Dietary CP increased (p < 0.05) the serum concentrations of both uric acid and creatinine in broilers. We concluded that dietary ENZ is more beneficial to younger broilers, independent of CP levels, and that its effect was restricted to body weight and the feed conversion ratio.

Effect of supplemental serine-protease from Bacillus licheniformis on growth performance and physiological change of broiler chickens

“…while albumin level in the plasma was elevated by supplement graded levels of protease 100, 200, and 300 mg/kg. It has been showed that the concentration of plasma albumin related to improving the immunity status in birds (Laborde et al 1995;Ding et al 2016;Saleh 2017;Ndazigaruye et al 2019). Our results are in harmony with Allouche et al (2015) who found that plasma protein concentrations were enhanced by dietary protease supplementations.…”

“…Increasing the supplemental protease levels were associated with decreasing the plasma levels of CHO, GLU, TG, and LDL-cholesterol and elevated HDL-cholesterol level in the current study. However, in another recent study (Ndazigaruye et al 2019) it has been reported that serum total protein, albumin, TG, CHO, creatinine, HDL-cholesterol, GOT, and GPT levels did not change in broiler fed diets with protease. The disagreement between our data and their data may be due to some factors such as the nutrient composition of the diets (sufficient/insufficient protein), enzyme used (source of enzymes, doses), and raw protein sources used which could alter some conditions of the digestive tract such as the pH.…”

“…Previous experiments conducted on serine protease and threonine and found there benefit on growth performance (Cowieson andRavindran 2008 Ayaşan et al 2009;Angel et al 2011;Fru-Nji et al 2011;Vieira et al 2013;Okan 2014a, 2014b;Ding et al 2016;Lin-Law et al 2019;Ndazigaruye et al 2019) and. In addition, it was reported that supplemental protease reduced nitrogen excretion (Aletor et al 2000;Bregendahl et al 2002;Canogullari et al 2009) and decreased feed costs, and consequently broiler industry's production.…”

Black soldier fly larvae oil as an alternative fat source in broiler nutrition

“…Malondialdehyde ( MDA ) was measured using the OxiSelect TBARS Assay kit (Cell Biolabs, Inc., San Diego, CA). Nitric oxide in serum samples was determined as described by Ndazigaruye et al. (2019) using the Griess reagent (Sigma-Aldrich, St. Louis, MO).…”

The Response of Broiler Chickens to Dietary Soybean Meal Reduction with Glycine and Cysteine Inclusion at Marginal Sulfur Amino Acids (SAA) Deficiency

“…The higher level of ALB could also be associated with synthetic amino acid supplementation in the diet [28]. UA concentrations are the indicator of amino acid utilization in chickens fed amino acid-deficient diets [29] and CRE is a product of creatine phosphate in muscle tissue, and its production is proportional to muscle mass [30]. The higher glucose level by a reduced protein diet could be because of the increased intake of nutrients and decrease insulin sensitivity affecting the transport and utilization of GLU [31].…”