Manipulation of plasma myo-inositol in broiler chickens: effect on growth performance, dietary energy, nutrient availability, and hepatic function

This study investigated the effects of graded levels of myo-inositol (INS) in diets containing 2 levels of available P on growth performance, nutrient retention, liver N, fat and Vitamin E contents, INS and alkaline phosphatase (ALP) concentrations in blood plasma. A total of 120 male Ross 308 broilers were allocated to 60 small floor pens each holding 2 birds. Two basal mash diets were formulated to be nutritionally adequate for chicks at that age, with one diet designed to have the recommended available P content (RP) (4.8 g/kg non-phytate P) and the other diet containing low available P (LP) (2.5 g/kg non-phytate P). The 2 basal diets were split in 3 batches each and 2 of the batches were supplemented with INS at 3.0 and 30 g/kg diet, with the remaining batch of each basal diet not supplemented, giving a total of 6 experimental diets. Diets were fed ad libitum to 10 pens from 7 to 21 d age following randomization. Feeding RP diets improved (P 0.05) influence bird growth, dietary AME, or nutrient retention coefficients. Feeding INS linearly increased (P 0.05) the endogenous losses (measured as sialic acid concentration) in excreta. Dietary INS did not influence (P > 0.05) the hepatic Vitamin E concentration but increased (P < 0.001) the ALP in the blood of birds fed 30 g/kg INS. In conclusion, highlevel dietary INS supplementation did not affect bird growth performance, mineral availability, and endogenous losses, and there were no interactions between INS and P

Partioning of dietary energy of chickens fed maize or wheat-based diets with and without a commercial blend of phytogenic feed additives

The aim of the study was to investigate the effects of a standardized mixture of a commercial blend of phytogenic feed additives containing 5% carvacrol, 3% cinnamaldehyde, and 2% capsicum on utilization of dietary energy and performance in broiler chickens. Four experimental diets were offered to the birds from 7 to 21 d of age. These included 2 basal control diets based on either wheat or maize that contained 215 g CP/kg and 12.13 MJ/kg ME and another 2 diets using the basal control diets supplemented with the plant extracts combination at 100 mg/kg diet. Each diet was fed to 16 individually penned birds following randomization. Dietary plant extracts improved feed intake and weight gain (P 0.05) but improved (P < 0.05) dietary NE by reducing the heat increment (P < 0.05) per kilogram feed intake. Feeding phytogenics improved (P < 0.05) total carcass energy retention and the efficiency of dietary ME for carcass energy retention. The number of interactions between type of diet and supplementary phytogenic feed additive suggest that the chemical composition and the energy to protein ratio of the diet may influence the efficiency of phytogenics when fed to chickens. The experiment showed that although supplementary phytogenic additives did not affect dietary ME, they caused a significant improvement in the utilization of dietary energy for carcass energy retention but this did not always relate to growth performance

Dietary xylanase increases hepatic vitamin E concentration of chickens fed wheat based diet

The study examined the effect of xylanase supplementation on apparent metabolizable energy (AME) and hepatic vitamin E and carotenoids in broiler chickens fed wheat based diets. A total of one hundred forty four male Ross 308 chickens were used in this study. Birds were randomly assigned to 3 dietary treatments (8 cages per treatment of 6 male broilers each) for 14 days from 7 to 21 day old. The control treatment was based on wheat-soyabean meal and was either unsupplemented or supplemented with either 1000 or 2000 xylanase units per kg diet. Orthogonal polynomial contrasts were used to test linear response to dietary xylanase activity. There was a positive linear relationship (P < 0.05) between dietary AME and doses of supplementary xylanase. A linear relationship (P < 0.05) was also observed between dosage of xylanase supplementation and hepatic vitamin E concentration and retention. In conclusion, xylanase supplementation improved dietary AME and increased hepatic vitamin E concentration which may have positive effects on the antioxidative status of the birds

Dietary modelling of nutrient densities: effect and response in different growing phases on growth performance, nutrient digestibility, litter quality and leg health in turkey production

An experiment was conducted to explore the time bound (different growth phases) effect of different dietary nutrient densities i.e., different energy and protein concentration while maintaining the ratio between the two, all with the same ideal amino acid profile, on litter quality and leg health (footpad dermatitis (FPD) and hock burn (HB)), when fed to growing turkeys. The effects of dietary nutrient modelling on growth performance parameters, water intake and excretion, dry matter (DMD), organic matter (OMD), crude protein (CPD) digestibility coefficients and apparent metabolisable energy (AME) were also examined, when fed to growing turkeys in varying growth phases. At twenty-eight days of age one hundred and seventy five male turkeys (BUT 8) were transferred to 35 floor pens, using stratified randomisation on body weight, 5 birds in a pen, all pens were equipped with plastic feed hoppers and drinkers. The experiment was a randomized block design consisting of 5 treatments (5 levels of CP and ME concentrations and 4 feeding/ growth phases). Each dietary treatment was replicated 7 times with 5 birds in each replicate. Feed and water were offered ad libitum throughout the experiment. Five dietary treatments, containing either 77, 85, 100, 110 or 120% of the crude protein (CP) and metabolisable energy (ME) content recommended by the breed standard. The whole experimental period of 16 weeks starting from 4 weeks of age was divided into 4 weeks standard growth phases: 4-8, 8-12, 12-16 and 16-20 weeks, finishing at 20 weeks of turkey’s age, according to commercial management guide for BUT 8 (Aviagen Turkeys Ltd.). Nutrient density had a positive and linear effect (P&lt;0.001) on weight gain, feed efficiency and dry matter digestibility (DMD) whereas the effect of nutrient density on dietary protein digestibility (CPD) only approached significance (P=0.081). As might be expected increasing nutrient density had a negative and linear effect on feed (P&lt;0.001) and water (P&lt;0.01) intake and did not affect the ratio between these two parameters. Increasing nutrient density had a positive effect on litter quality (linear (P&lt;0.001)), with both the litter moisture (P&lt;0.01) and the litter score decreasing (P&lt;0.001). Conversely litter ammonia concentration increased (P&lt;0.001) as nutrient density increased, similarly as nutrient density increased so did the prevalence of hock burn (P&lt;0.01). Notably there was no effect (P&gt;0.05) of treatment on FPD. The results suggest that an increase in nutrient concentration can reduce the moisture content of the litter and so improve overall litter quality. However, the incidence of hock burn increased with the high nutrient density diets, suggesting that factors other than the litter moisture alone may contribute the occurrence of leg health problems in turkey production

Effect of wheat distillers dried grains with solubles and exogenous xylanase on laying hen performance and egg quality

Despite the rapid increase in the use of wheat distillers dried grains with solubles (DDGS) within the poultry sector, little information is available on how the long-term feeding of this by-product will affect the performance of laying hens. This experiment examined the effect of wheat DDGS, with and without exogenous xylanase on dietary apparent metabolizable energy (AME), total tract dry matter retention (DMR), nitrogen retention (NR), fat digestibility (FD) coefficients, feed intake (FI), bodyweight gain (BWG), eggs laid, mean egg weight, egg mass output, and egg quality characteristics including albumin height (AH), Haugh units (HU), yolk color, eggshell strength, and thickness. A total of 320 Hy-Line brown laying hens were randomly allocated to 80 enriched layer colonies (groups of 4). A total of 2 control wheat-soybean meal-based diets were formulated to contain 11.60 MJ/kg. One of the diets contained 300 g/kg wheat DDGS, while the other was DDGS free, with a respective crude protein content of 171.1 g/kg and 166.5 g/kg. Both diets were divided by 2 and half of them were supplemented with 2,500 U/kg of xylanase, resulting in 4 diets in total. Data was analyzed as a 2 × 2 factorial arrangement of treatments with analysis of variance (ANOVA). Diets were fed ad libitum from 17 to 43 wk of age and data was collected from 23 to 43 wk. The inclusion of wheat DDGS reduced (P < 0.001) dry matter retention (DMR), FI, BWG, eggs laid, mean egg weight, and egg mass. However, xylanase supplementation improved AME and NR in diets containing wheat DDGS and FD in diets without DDGS (DDGS × xylanase, P < 0.05) and tended to improve (P < 0.10) BWG and egg mass output. For egg quality measurements, the inclusion of DDGS improved (P = 0.046) HU values, eggshell strength (P < 0.001), and increased (P < 0.001) yolk color intensity. This experiment showed xylanase can be used to improve the AME and NR of DDGS-based diets. However, the long-term feeding of 300 g/kg wheat DDGS negatively impacts the productive performance of hens

Evaluation of novel protease enzymes on growth performance and apparent ileal digestibility of amino acids in poultry: enzyme screening

Three experiments were conducted to evaluate eight neutral and six acid proteases on growth performance and apparent ileal amino acid digestibility (AID) of poults (Experiment 1) or chicks (Experiments 2 and 3). Two basal diets were formulated: a nutrient adequate positive control (PC), which met or exceeded the nutrient requirements for poults (Experiment 1) or chicks (Experiments 2 and 3) and a negative control (NC) formulated to achieve 85% (Experiments 1 and 2) or 80% (Experiments 3) of the requirement for protein and amino acids. Phytase was included in all diets to provide 500 phytase units (FTU)/kg and xylanase was included in all diets to provide 10,000 (Experiments 1 and 2) or 16,000 (Experiments 3) xylanase units (BXU)/kg. Proteases were supplemented in the NC diet at an equivalent amount of enzyme protein to create 16 experimental diets. There were five birds/pen and 10 replicate pens per treatment in each experiment. In experiment 1, birds fed the PC diet gained more (P < 0.05) than birds fed the NC. There were no differences in growth performance in birds fed the PC or NC in experiments 2 or 3. In all three experiments, birds fed the NC supplemented with neutral protease 1 had reduced (P < 0.05) feed intake (FI) or body weight gain (BWG) and increased (P < 0.05) feed conversion ratio (FCR) compared with birds fed the NC. Birds fed the NC diet supplemented with neutral protease 3, 7 (Experiment 1), or acid protease 4 (Experiment 3) had increased (P < 0.05) FCR and birds fed neutral protease 6 (Experiment 2) had reduced (P < 0.05) BWG compared with birds fed the NC. Apparent ileal amino acid digestibility was improved (P < 0.05) with protease supplementation to the NC diets (Experiment 1 or 3), but this was dependent on the protease and the amino acid. In conclusion, novel protease supplementation improved AID of amino acids but this was not reflected in improvements in growth performance of poults or chicks

Exogenous tannase improves feeding value of a diet containing field beans (Vicia faba) when fed to broilers

A total of 72 male Ross 308 broilers were used in a study to investigate the effect of dietary tannase on apparent metabolisable energy (AME), coefficients of dry matter retention (DMR) and nitrogen retention (NR) and fat digestibility (FD) of a diet containing 300 g/kg field beans (Vicia faba). Growth performance variables and gastrointestinal tract development were also measured. Two treatments were used in this study: control (C) and C + 3400 tannase units (TU) per kg feed. Diets were formulated to be nutritionally adequate with the exception that the AME was lower than recommended (12.65 vs 12.97 MJ/kg, respectively). Inclusion of tannase increased AME by 0.4 MJ/kg DM. Tannase supplementation improved dietary DMR, NR and FD by 2.8%, 3.2% and 6.5%, respectively. Birds given tannase had 4.4% reduction in feed intake and 2.6% improvement in gain to feed ratio (P < 0.05). Compared to control diet, birds given tannase had reduced relative to body weight (%BW) proventriculus and gizzard and pancreas weights, 3.29% vs 3.09% and 0.47% vs 0.44%, respectively. The mechanisms of action of the studied enzyme require further elucidation

Immune modulation, growth performance, and nutrient retention in broiler chickens fed a blend of phytogenic feed additives

his study aimed to assess the effect of a commercial blend of phytogenic feed additives (PA), comprising 5% carvacrol, 3% cinnamaldehyde, and 2% capsicum oleoresin on the modulation of immune biomarkers of broiler chickens, their growth performance, dietary energy, and nutrient retention. Four-hundred day-old birds were assigned to one of four dietary treatments. Two control diets based on either wheat (WC) or maize (MC) were each given with and without PA at 100 g/t. Growth performance variables including feed intake (FI), weight gain (WG), and feed conversion ratio (FCR) were recorded. Dietary N-corrected apparent metabolizable energy (MEn), dry matter (DMR), nitrogen (NR), and fat retention (FR) coefficients were also determined. Gene expression of immune biomarkers (cytokines) were determined in caecal tonsil tissue from 21 d old birds. Expression of IL2, IL18, IL10, and IL17C in the caecal tonsils were upregulated (P 0.05) change in expression levels in birds fed MC diets. Feeding MC diets gave greater FI (P 0.05) by cereal type. Supplementary PA improved FI (P < 0.05), WG (P < 0.001), FCR (P < 0.05), MEn (P < 0.05), MEn: GE ratio (P < 0.05), and FR (P < 0.05). In conclusion, dietary inclusion of PA improved overall growth performance variables, energy, and nutrient retention and intestinal cytokine expression

Variability of amino acid digestibility in different field bean cultivars for broilers

1. The amino acid composition of 10 different UK-grown field bean cultivar samples from the same harvest year were determined. 2. Diets included each bean sample at a level of 200 g/kg feed compared against a control diet formulated with only soyabean sources, whereby the beans replaced the soyabean meal, and were used to compare ileal amino acid digestibility. The amino acid digestibility coefficients for the bean samples were obtained via substitution method. 3. The data showed that one field bean sample, cultivar Sultan, had a lower amino acid digestibility (P<0.05) than that of the other nine . This sample had a higher tannin content that may have affected amino acid digestibility