Dietary substitution of maize with processed cocoyam (Xanthosoma sagittifolium) as energy source for finisher broilers production

Energy feed source like maize is expensive contributing about 50-55% of the cost of poultry and pig diets. Thus, the study was carried out to determine the dietary substitution of maize with soaked cocoyam Xanthosoma sagittifolum as energy source for finisher broiler production. The soaked cocoyam tuber meal was used to replace yellow maize in the diets of finisher broilers. Xanthosoma cocoyam corms were harvested, cleaned of soil and chopped into bits of about 0.2 cm. The chopped tannia was soaked in water in a large vat for 24 hours to reduce the ant nutrients and later on separated from the water and dried with microwave oven. The dried cocoyam was milled and then used. The proximate chemical composition showed that soaked cocoyam tuber meal contained 8.05% moisture, 91.95% dry matter, 10.08% ash, 2.01% crude protein, 1.60% ether extract, 3.80% crude fibre, 74.46% NFE and 3158.92Kcal/kg DM metabolizable energy. In the finisher broiler trial, the control diet contained maize as the main energy source while diets 2, 3, 4 and 5 contained 15%, 20%, 25%, and 30% soaked cocoyam tuber meal finisher diet was fed to a group of 30 broiler chicks for 4 weeks using completely randomized design. Each treatment was further grouped into 3 replicated of 10 birds each. The broilers were kept in deep litter and given feed and water ad libitum. Parameters measured included: initial body weight, find body weight, body weight gain, feed intake, feed conversion ratio, cost of production and carcass characteristic. In the finisher feeding trial, the finisher broilers on the control diet, diet 5 (30% SCYM), and diet 3 (20% SCYM) recorded similar feed intake which were significantly different (P<0.05) from those on the other diets. In terms of body weight gain, the finisher broilers on 20% soaked cocoyam tuber meal diet recorded significantly (P<0.05) high body weight than those on other diets while the finisher broilers on 25% soaked cocoyam tuber meal recorded the poorest body weight gain. It appeared that, the finisher broilers could not tolerate high levels of soaked cocoyam tuber meal in their diets. Cost of production (cost of feed x feed conversion ratio) was lowest for diet 5 (30% SCYM) N375 versus N422.99 for control diet in the finisher trial. The internal organs expressed as percent of the live weight were not affected by the treatments. The finisher broilers on diet 3 recorded the highest dressing out percentage of 73.90.There were no significant difference (p<0.05) on percentage wings and back cut of the finisher broiler group in all the diets. The finisher broilers on diet 4 (25% SCYM) yielded the highest percent breast muscle of 32.4% followed by those on 15% SCYM (diet 2) and 20 SCYM (diet 3). The finisher broilers on the control diet yielded the highest percent thigh of 18.3% and the poorest were those on diet 2(15% SCYM). The results of the trial have shown that soaked cocoyam tuber meal can be used to substitute maize at 20% in the diets of finisher broilers without affecting the weight gain, feed intake and feed conversion ratios as indicated in this study.

Intake of Nuts or Nut Products Does Not Lead to Weight Gain, Independent of Dietary Substitution Instructions: A Systematic Review and Meta-Analysis of Randomized Trials

ABSTRACT Several clinical interventions report that consuming nuts will not cause weight gain. However, it is unclear if the type of instructions provided for how to incorporate nuts into the diet impacts weight outcomes. We performed a systematic review and meta-analysis of published nut-feeding trials with and without dietary substitution instructions to determine if there are changes in body weight (BW) or composition. PubMed and Web of Science were searched through 31 December 2019 for clinical trials involving the daily consumption of nuts or nut-based snacks/meals by adults (≥18 y) for &gt;3 wk that reported BW, BMI, waist circumference (WC), or total body fat percentage (BF%). Each study was categorized by whether or not it contained dietary substitution instructions. Within these 2 categories, an aggregated mean effect size and 95% CI was produced using a fixed-effects model. Quality of studies was assessed through the Cochrane risk-of-bias tool. Fifty-five studies were included in the meta-analysis. In studies without dietary substitution instructions, there was no change in BW [standardized mean difference (SMD): 0.01 kg; 95% CI: −0.07, 0.08; I2 = 0%] or BF% (SMD: −0.05%; 95% CI: −0.19, 0.09; I2 = 0%). In studies with dietary substitution instructions, there was no change in BW (SMD: −0.01 kg; 95% CI: −0.11, 0.09; I2 = 0%); however, there was a significant decrease in BF% (SMD: −0.32%; 95% CI: −0.61%, −0.03%; I2 = 35.4%; P &lt; 0.05). There was no change in BMI or WC for either category of studies. Nut-enriched diet interventions did not result in changes in BW, BMI, or WC in studies either with or without substitution instructions. Slight decreases in BF% may occur if substitution instructions are used, but more research is needed. Limitations included varying methodologies between included studies and the frequency of unreported outcome variables in excluded studies.

Ruminal fermentation and digestion of cattle diets with total and partial replacement of soybean meal by a slow-release urea product

One in vitro assay and one in vivo trial with ruminally cannulated Holstein steers were conducted to evaluate the effects of a dietary substitution of soybean meal by a urea and slow-release urea source of fermentation and degradation of diets for cattle. The experimental diets consisted of the total mixed rations defined as the control with soybean meal (SBM), U (urea), SRU (slow-release urea), and SRU+U+AA (0.42% + 0.42% + 1% amino acids methionine and lysine). The dietary substitution of SBM by U or SRU reduced (P &lt; 0.05) the total gas production (V), microbial mass and degradation at 72 h incubation under the in vitro conditions, as well as the degradation rate (c) and the total volatile fatty acids (VFA) in the rumen of the steers; however, when the dietary substitution of SBM was by U+SRU+AA, those values did not decrease. In the steers, the dietary substitution of SBM by U and SRU reduced the ruminal degradation rate and the total VFA, and increased the ammonia N, but when SBM was substituted by U+SRU+AA in the diets, these changes were not observed. No advantage of SRU over U was found. The dietary substitution of SBM by U, SRU, U+SRU+AA did not modify the molar proportion of the VFA in the rumen nor were there changes in the nutrient digestion or excretion. Both the in vitro assay and the in vivo trial indicated that replacing SBM with U or SRU increases the ruminal ammonia N concentrations and reduces the degradation rate in the rumen, although those undesirable findings were not found when the SBM was replaced by U+SRU+AA. Therefore, it is feasible to replace the SBM with a combination of urea, slow-release urea, lysine and methionine in the diet for the ruminants.