Novel sfericase protease improves amino acid digestibility of soybean meal and rapeseed meal in broiler chickens.

1. Two experiments were conducted to explore the effects of an exogenous sfericase protease on the apparent ileal nutrient digestibility of soybean meal (SBM) and rapeseed meal (RSM) in broiler chickens.2. In each experiment, a total of 256 sixteen-day-old male Cobb 500 broilers were fed one of four semi-purified experimental diets, comprising two different batches (A and B) of samples for either SBM (Exp. 1) or RSM (Exp. 2) without or with an exogenous sfericase (0 or 30,000 NFP/kg). Each experimental diet was fed to eight replicate pens of broiler chickens from 16 to 21 d of age (eight birds per cage), and ileal digesta were collected for measuring the digestibility coefficients.3. In Exp. 1, the amino acid digestibility was greater (P < 0.05) in SBM B compared with SBM A for Arg and Val, and a similar trend (P < 0.1) was observed for Tyr, Leu and Thr. Exogenous sfericase increased (P < 0.10) digestibility of most of amino acids except Gly, His and Trp. There was an interaction between SBM source and sfericase, whereby digestibility of P, N and Asp was increased by sfericase for SBM B but not for SBM A. In Exp. 2, there was no interaction (P > 0.05) between RSM source and sfericase for ileal nutrient digestibility. Digestibility was greater in RSM A compared to RSM B for all non-essential AA and most essential AA (except for Trp), while the reverse was noted for Ca and P (P < 0.05). Exogenous sfericase increased (P < 0.1) digestibility for all amino acids except Cys and Met.4. In conclusion, the current studies showed that both SBM and RSM batches influenced amino acid digestibility. Sfericase protease supplementation increased amino acid digestibility for both SBM and RSM. The digestibility effects were greater in the SBM batch with low digestibility for N and Asp which was in line with an increase in P digestibility.

A meta-analysis on the effect of canthaxanthin on egg production in brown egg layers.

A meta-analysis was conducted to evaluate the effect of the carotenoid canthaxanthin on production performance in layer hens. The data set contained 576 performance measurements from 34 trials. The trials were all conducted according to a similar experimental protocol from 1997 to 2012. The age of the animals ranged from 21 to 65 weeks. The experimental diets were predominantly wheat/SBM based, fed in mash form ad libitum. Depending on the trial and the treatment group considered, canthaxanthin supplementation was in the range of 0 to 8 mg/kg of feed.Using a linear mixed model regression applied to all 34 trials simultaneously, significant dose-dependent increases were found in egg yolk mass (+0.53% per ppm of canthaxanthin inclusion in the feed, P < 0.001), in egg mass (+0.47% per ppm, P = 0.0132), egg weight (+0.17% per ppm, P = 0.046), and in feed intake (+0.32% per ppm, P = 0.0054). A numerical increase was found in egg production (+0.28%, P = 0.14). The FCR decreased numerically (-0.24% per ppm, P = 0.36). The deposition of canthaxanthin in the egg yolk was 2.25 ppm per ppm of canthaxanthin in the feed (P < 0.001). It is concluded that in addition to egg yolk pigmentation, antioxidant effect, enhanced reproduction, and immune-modulation, canthaxanthin can significantly increase egg mass, thereby enhancing the productivity of the flock. Mechanisms relating to carotenoid metabolism and functions in avian species are a new research area that will require further investigation to explain the observed effects.

Simultaneous inclusion of sorghum and cottonseed meal or millet in broiler diets: effects on performance and nutrient digestibility.

Two experiments were conducted to investigate the use of sorghum, cottonseed meal and millet in broiler diets and their interaction when they are used simultaneously. In Experiment 1, a corn-soybean meal control diet was compared with eight experimental treatments based on low tannin sorghum (S30, S45 and S60), cottonseed meal (CM15, CM40) or both ingredients included in the same diet (S30/CM40, S45/CM25 and S60CM15). Results showed that BW gain was not affected by the inclusion of sorghum or cottonseed meal. However, feed intake tended to be affected by the cereal type with the highest values with sorghum-based diets. Feed conversion ratio increased (P<0.001) with sorghum-based diets compared with the control diet, whereas a combination of cottonseed meal and sorghum in the same diet did not affect the feed conversion ratio. Significant differences (P<0.001) were observed in apparent ileal digestibility (%) of protein and energy with the cottonseed meal and sorghum/cottonseed meal-based diets having lower protein and energy digestibility compared with corn-based diets. In Experiment 2, a control diet was compared with six diets in which corn was substituted at 60%, 80% or 100% by either sorghum or millet and other three diets with simultaneous inclusion of these two ingredients (S30/M30, S40/M40, S50/M50). Single or combined inclusion of sorghum and millet resulted in similar feed intake and growth performance as the control diet. Apparent ileal digestibility of protein and energy was higher with millet-based diets (P<0.001). Total tract digestibility of protein in sorghum and millet-based diets tended to decrease linearly with the increasing level of substitution. Sorghum-based diets resulted in lower total tract digestibility of fat compared with millet and sorghum/millet-based diets (P<0.001). Higher total tract digestibility of starch were obtained with the control diet and millet-based diets compared with the sorghum-based treatments. Results of the two experiments suggest that broiler growth performance was not affected by the dietary level of sorghum, millet or cottonseed meal. Nutrient digestion can, however, be affected by these feed ingredients.

Inclusion of sorghum, millet and cottonseed meal in broiler diets: a meta-analysis of effects on performance.

A meta-analysis was conducted (i) to evaluate broiler response to partial or total substitution of corn by sorghum and millet and (ii) to determine the effect of soybean meal replacement by cottonseed meal in broiler diet. The database included 190 treatments from 29 experiments published from 1990 to 2013. Bird responses to an experimental diet were calculated relative to the control (Experimental-Control), and were submitted to mixed-effect models. Results showed that diets containing millet led to similar performance as the corn-based ones for all parameters, whereas sorghum-based diets decreased growth performance. No major effect of the level of substitution was observed with millet or cottonseed meal. No effect of the level of substitution of sorghum on feed intake was found; however, growth performance decreased when the level of substitution of corn by sorghum increased. Cottonseed meal was substituted to soybean meal up to 40% and found to increase feed intake while reducing growth performance. Young birds were not more sensitive to these ingredients than older birds since there was no negative effect of these ingredients on performance in the starter phase. Results obtained for sorghum pointed out the necessity to find technological improvements that will increase the utilization of these feedstuffs in broiler diet. An additional work is scheduled to validate these statistical results in vivo and to evaluate the interactions induced with the simultaneous inclusions of sorghum, millet and cottonseed meal in broiler feeding.