Effect of Pre-Treating Dietary Green Seaweed with Proteolytic and Fibrolytic Enzymes on Physiological and Meat Quality Parameters of Broiler Chickens

The use of seaweeds as nutraceuticals in chicken diets is limited by high fibre levels and low protein digestibility. Therefore, we tested the effect of pre-treating dietary seaweed (Ulva sp.) with a combination of protease and fibrolytic enzymes on physiological and meat quality parameters of Cobb 500 broilers. Five dietary treatments were formulated by including untreated (T1); fibrolytic (12 g/kg) enzyme-treated (T2); fibrolytic (12 g/kg) and protease (5 g/kg) enzyme-treated (T3); fibrolytic (12 g/kg) and protease (10 g/kg) enzyme-treated (T4); fibrolytic (12 g/kg) and protease (15 g/kg) enzyme-treated (T5) seaweed (35 g/kg) in a standard broiler diet. Three hundred, two-week-old chicks (239.3 ± 8.57 g live weight) were evenly distributed to 30 replicate pens to which the diets were then randomly allocated. Birds fed diet T1 had the highest feed intake (1144.5 g/bird). Neither linear nor quadratic trends were recorded for growth performance and carcass traits in response to protease pre-treatment levels. Gizzard weight linearly increased, while symmetric dimethylarginine, calcium, meat pH24, and hue angle24 quadratically responded to protease levels. Diet T1 promoted the lowest serum phosphorus levels (3.37 mmol/L). In conclusion, pre-treatment of seaweed with a combination of protease and fibrolytic enzymes did not improve diet utilization, physiological parameters, and meat quality in broilers.

The Effect of Green Tea (Camellia sinensis) Leaf Powder on Growth Performance, Selected Hematological Indices, Carcass Characteristics and Meat Quality Parameters of Jumbo Quail

Green tea leaves contain a wide range of active bio-compounds that are essential for sustainable quail intensification; however, its feed value is not known for the Jumbo quail. Therefore, this study evaluated the effect of different levels of green tea leaf powder (GTLP) on physiological and meat quality parameters of the Jumbo quail. One-week-old chicks (n = 350; 56.1 ± 2.12 g live-weight) were evenly distributed to 35 replicate pens and reared on five experimental diets formulated as follows: a standard grower diet with zinc-bacitracin (PosCon), a standard grower diet without zinc-bacitracin (NegCon), and NegCon diet treated with 10 (GT10), 25 (GT25) and 50 g/kg (GT50) of GTLP. Weight gain linearly decreased in week 2 but increased in week 4, whereas feed conversion efficiency linearly declined in weeks 2 and 3 as GTLP levels increased. Overall feed intake, carcass yield, and caecum and colon weights showed a linear increase with GTLP levels. Hematological parameters fell within the normal ranges reported for healthy quail. The GT10 group showed larger liver weights than the PosCon and NegCon groups. It was concluded that dietary inclusion of GTLP enhances overall feed intake and carcass performance but not feed efficiency, hematological and meat quality parameters of Jumbo quail.

Partial replacement of soybean products with canola meal in indigenous chicken diets: size of internal organs, carcass characteristics and breast meat quality

While the use of canola meal (CM) as an alternative to soybean meal in broiler diets is well-documented, there is no information on the utility of this valuable by-product for slow-growing indigenous chickens. This study was, therefore, conducted to evaluate the effects of partially replacing soybean products in a chicken grower diet with graded levels of CM on carcass characteristics, relative organ sizes and meat quality in Potchefstroom Koekoek (PK) cockerels. A total of 175 PK cockerels (342.6 ± 15.2 g body weight, 5 wk old) were randomly allocated to 25 pens. Five isonitrogenous and isoenergetic grower diets containing 0, 3.75, 6.25, 8.75, and 17.5% of CM were then randomly allocated to the pens (experimental units). After 12 wk of feeding, chickens were slaughtered to measure carcass traits, size of internal organs and meat quality traits. There were no effects of graded levels of CM on carcass weights. Wing weight increased quadratically [y = 6.27(±0.23) + 0.23 (±0.063) x-0.009 (±0.0003) x2; R2 = 0.28] in response to incremental levels of dietary CM. Drumstick, vertebrae, liver, and small intestine weights linearly increased (P < 0.05) in response to incremental levels of dietary CM. Redness (a*), initial meat pH (pHo), and shear force linearly increased (P < 0.05) but lightness (L*) and water holding capacity decreased with an increase in CM inclusion levels. However, there were no significant linear and quadratic trends for yellowness (b*), ultimate pH (pHu), drip loss, and cooking loss in response to incremental levels of CM. There were also significant quadratic trends for mineral contents of the meat with the exception of iron (Fe). It can be concluded that inclusion of CM in place of soybean products had no negative impact on carcass traits, organ size and meat quality traits of indigenous PK chickens.

A Nutritional Evaluation of Insect Meal as a Sustainable Protein Source for Jumbo Quails: Physiological and Meat Quality Responses

The use of insect meals in place of soybean meal in diets is critical for sustainable intensification of poultry production, but the utility of this alternative dietary protein source is unknown for the Jumbo quail. Therefore, this study investigated the effect of partial substitution of soybean with black soldier fly larvae (BSFL) meal on feed intake, physiological, and meat quality parameters of Jumbo quails. Three hundred and fifteen mixed-gender quails (53.8 ± 5.19 g live-weight) were reared on five isonitrogenous and isoenergetic experimental diets formulated by replacing soybean products with BSFL meal at 0 (BSFL0), 25 (BSFL25), 50 (BSFL50), 75 (BSFL75), and 100 (BSFL100) g/kg. Feed intake, body weight gain, gain-to-feed ratio (G:F), blood parameters, and carcass and meat quality traits were determined. Quadratic trends were observed for overall feed intake (y = 605 (±17.56) + 2.1 (±0.82)x − 0.02 (±0.008)x2; R2 = 0.20; p = 0.023) and overall body weight gain (y = 155 (±4.70) + 0.57 (±0.22)x − 0.005 (±0.002)x2; R2 = 0.22; p = 0.026) in response to BSFL levels. However, there were neither linear nor quadratic trends for meat quality and blood parameters, except for albumin-to-globulin ratio. Only gizzard size linearly increased (y = 0.05 (±0.004)x + 2.3 (±0.09); R2 = 0.18; p = 0.04) with BSFL levels. We concluded that BSFL meal could replace soybean products in Jumbo quail diets at 54 g/kg without compromising weight gain and meat quality.