Poult Performance Research Articles

Influence of varying branched-chain amino acid ratio in diets containing corn gluten meal, L-isoleucine, and L-valine on 0–21 d turkey poult performance, relative mTOR activation, and apparent ileal amino acid digestibility

Influence of varying branched-chain amino acid ratio in diets containing corn gluten meal, L-isoleucine, and L-valine on 0–21 d turkey poult performance, relative mTOR activation, and apparent ileal amino acid digestibility

Hygienic feed manufacturing strategies improve pelleting efficiency while maintaining early turkey poult performance and tibia mineralization

Hygienic feed manufacturing strategies improve pelleting efficiency while maintaining early turkey poult performance and tibia mineralization

Adequate Levels of Zinc and Copper on Turkey Poult Performance, Immunological Response, and Skeletal Health.

In this study, the impact of varying dietary zinc (Zn) and copper (Cu) levels on the growth, immunological response, and skeletal health of developing turkey poults was investigated. For 0-4 and 5-8 weeks of age, respectively, three Zn levels of 50, 70, and 90mg/kg and 45, 65, and 85mg/kg were employed. Three Cu levels, namely 8, 12, and 16mg/kg for 0-8 weeks of age, were also utilized. There were 288 (9 × 4 × 8) day-old turkey poults with equal body weight that were randomly assigned to 9 treatments, each consisting of 4 replicates and 8 poults per replicate. In comparison to other dietary combinations, there was a significant (P ≤ 0.05) increase in body weight gain observed in the 90 and 85mg Zn/kg with 16mg Cu/kg diet during 0-4 and 0-8 weeks of age, respectively, and the 70 and 65mg Zn with 16mg Cu /kg diet during 0-4 and 0-8 weeks of age, respectively. When compared to low levels of zinc in the diet at 5-8 and 0-8 weeks of age, respectively, feed conversion ratio was shown to be significantly (P ≤ 0.01) better with 90 and 85mg Zn/kg diet. In a similar pattern, feed utilization efficiency was considerably (P ≤ 0.01) higher at 16mg Cu/kg diet than it was at lower Cu levels in the diets given to the animals over the 0-4 week period. Compared to other dietary combinations, there was a substantial (P ≤ 0.01) improvement in cell-mediated immune response (foot web index to PHAP) and humoral immune response (HA titer to SRBC) when 85mg zinc and 16mg copper/kg diet was consumed at 0-4 and 5-8 weeks of age. At greater dietary Zn and Cu levels than its lower values, the weight of the spleen and thymus was considerably (P ≤ 0.05) higher. In a dietary combination of 90mg Zn with 16mg Cu/kg during 0-4 and 85mg Zn with 16mg Cu/kg diet during 5-8 weeks of age, respectively, there were significantly (P ≤ 0.05) greater bone width (proximal and distal), tibia bone ash, calcium, and phosphorus detected respectively. Significantly (P ≤ 0.01) greater Zn and Fe contents were found in the tibia bone at 90 and 85mg Zn/kg diet, respectively, compared to values obtained at other Zn levels in the diet throughout 0-4 and 5-8 weeks of age. During the first 8 weeks of life, a diet containing 12mg of copper per kilogram was shown to have a significantly (P ≤ 0.05) increased Zn and Fe content in the tibia bone compared to other levels. It is possible to draw the conclusion from the data that, for growing turkey poults, dietary combinations of 90mg Zn/kg with 16mg Cu/kg diet and 85mg Zn with 16mg Cu/kg diet between 0 and 4 and 5-8 weeks of age, respectively, were sufficient for optimum development, immunity, and skeletal health indices.

EFFECTS OF DIETARY INCLUSION OF VARIED LEVELS OF BUTYRIC ACID AS ANTIBIOTIC ON THE PERFORMANCE OF TURKEY POULTS

The effects of butyric acid supplemented diets on growth performance of turkey poults were examined in a 49-day experiment using one hundred and sixty (160) (one-day old) Nicholas turkey poults. The experimental design was a Completely Randomized Design. Poults were brooded for 7 days, after which they were allotted to 4 dietary treatments with 5 replicates of 8 birds per replicate. Treatment 1(T1) was the basal diet with no supplement while treatments 2 (T2), 3 (T3), and 4(T4) were supplemented with antibiotics, 0.2% butyric acid and 0.4% butyric acid respectively. Feed was offered ad-libitum. Final weight and weight gain of poults fed control, antibiotics and 0.2% butyric acid supplemented diets were similar but significantly (p<0.05) higher than birds fed 0.4% butyric acid diet. Significant higher feed intake was observed in birds fed control and antibiotics diets while the least was recorded in birds fed 0.4% butyric acid diet. It was observed that 0.2% butyric acid appears to be a viable alternative to antibiotics growth promoter in turkey diets without any detrimental effect on the productive performances.

Effect of brooding conditions on the blood chemistry and performance of turkey poults

Hematologic parameters and the levels of certain plasma metabolites offer an objective measure, and real-time insight into the physiological status of an animal. We hypothesized that blood chemistry analysis in brooding poults varies with even minor differences of temperature and can affect poult performance. A total of 2240 1-d-old turkey hens were assigned randomly to one of 4 treatments [Control (C) = 32C and 60%RH; Cold stress (CS) = 29C and 60%RH; Heat stress (HS) = 35C and 60%RH; and Heat stress plus Humidity (HHS) = 35C and 75%RH]. In all the treatments, the temperatures were lowered 2 degrees Celsius the first week, and 1.5 degrees Celsius each week thereafter. The relative humidity was maintained constant, as much as possible, throughout the 35 d duration of the experiment. Brooding treatment affected pH, partial carbon dioxide (pCO2), potassium (K), and sodium (Na). The treatments HS and HHS had higher pH and K, and lower pCO2 and K in the blood. These changes suggest an attempt by the poults to cool down by increased water intake and panting. Furthermore, by the end of the experiment more birds in these two treatment groups had distended crops, possible to increased water intake also. The increase of ketone in the plasma, at 3 d of age, of poults from the two warmest brooding conditions (HS and HHS) suggests that these birds were consuming less feed and using more fat as its main fuel source. Furthermore, at 28 d of age significantly more poults from HS and HHS had reduced ventricular contractility of their hearts. However, no significant differences in the concentration of creatinine kinase (CK) or cardiac troponin I (cTnI) were found between treatments. In conclusion, this research revealed that blood parameters were influenced by minor temperature and humidity changes. Warmer brooding temperatures resulted in a higher incidence of pendulous crop. Overall, there were no significant differences in the estimated BW between the treatments. Further research is needed to optimize the number of samples needed and the time of sampling to optimize brooding conditions. We also need to investigate blood parameters that can reveal reduced contractility of the heart and if the reduced myocardial contractility from birds kept at a higher temperature and relative humidity predisposes them to dilated cardiomyopathy or other metabolic diseases.

Effect of Dietary Supplementation of L-Valine on Growth, Immunocompetence Traits, Carcass Quality and Meat Composition of Turkey Poults

Background: Valine is an important amino acid and its deficiency may result in reduced growth and immunity. However, studies in turkeys are limited. Hence a study was conducted to assess the effect of supplemental L-valine (L-val) on growth performance, immunocompetence traits, carcass quality and meat composition of turkey poults. Methods: Day old turkey poults (n= 96) were distributed into four dietary treatment groups:T1-basal diet, T2-T1+0.04% L-val, T3- T1+0.08% L-val , T4- T1+0.12% L-val, having three replicates of 8 birds each. Result: No significance difference observed in average weekly body weight (BW), body weight gain (BWG) and feed conversion ratio (FCR) of birds throughout experimental period except at 7th week where T2 and T3 poults had a significantly higher (P less than 0.05) BW, BWG and significantly better (P less than 0.05) FCR. HA titre was significantly higher (P less than 0.05) in T3. Per cent breast weight was significantly higher (P less than 0.05) in T3. Percent crude protein level in breast muscle of turkey poults was significantly higher (P less than 0.05) in T3. Thus, supplementation of L-val @ 0.08% in turkey poults resulted in significantly better humoral immune response, higher percent breast yield and higher percent crude protein in breast meat.

Effects of Dietary Amino Acid Density and Exogenous Protease Inclusion on Growth Performance and Apparent Ileal Amino Acid Digestibility in Turkeys

Protein is one of the most expensive nutrients in poultry diets. In an effort to minimize feed costs, protein digestion and utilization by the animal must be carried out as effi­ciently as possible. The objective of this experiment was to evaluate the effects of dietary amino acid density and exogenous protease inclusion on growth performance and amino acid digestibility in turkey poults. Hybrid turkey poults (n = 780) were fed diets formulated to provide low (LAA) or adequate (AAA) amino acid density (approxi­mately 91 and 100% of the NRC4 recommended requirement for digestible Lys, respec­tively) with each diet being fed with or without an exogenous protease. Poults received experimental diets from d 1 to 42 of age. Growth performance metrics were calculated from pen weights and feed consumption was recorded throughout each experiment, and digestibility data were obtained from analysis of ileal contents. Data were analyzed using SAS 9.4 with pen as the experimental unit and pen location as the blocking factor. For the overall experiment (d 0 to 42), poults fed AAA diets had improved (P < 0.01) ADG, ADFI, and feed conversion ratio (FCR) compared to those fed LAA diets. There was no difference (P > 0.14) in poult performance due to protease inclusion. There was an amino acid density × protease interaction (P = 0.01) for apparent ileal amino acid digestibility (AIAAD) of Trp. There was no difference in AIAAD coefficients of Trp in the LAA diets with or without protease. However, in the AAA diets, poults not receiving protease had greater AIAAD of Trp than those consuming protease. There was no difference (P > 0.09) in AIAAD coefficients of Arg, Met, Cys, Thr, Ile, Leu, Lys, or Val due to dietary amino acid density or protease inclusion. Greater amino acid density improved growth performance in poults up to 42 d of age. No improvement in growth performance was observed when poults were fed an exogenous protease in the starter phase, although protease inclusion increased ADG by 5.3% and ADFI by 4.1% during the grower phase. There was no benefit of increased dietary amino acid density or protease inclusion on AIAAD in poults.

The effect of a direct-fed microbial (PrimaLac) and fat inclusion on performance and energy metabolism in broiler chicks and turkey poults

Two battery trials were conducted to determine the effects of dietary direct-fed microbial (DFM) and dietary fat inclusion on broiler chick and turkey poult performance and dietary apparent metabolizable energy, nitrogen corrected (AMEn) when fed corn, wheat, and soy diets. For both experiments, a 2 x 2 factorial experimental design was used with supplemental fat at low (1%, LF) or high (6%, HF) levels and DFM inclusion (0 or 0.91 kg/ton) as main effects. Dietary treatments were randomly assigned to 72 cages of birds and fed for 21 days. Growth performance was measured weekly, and cecal contents were collected for volatile fatty acid (VFA) analysis on day 21. Fat supplementation resulted in increased body weight gain (BWG) in both broilers and turkeys. Specifically, in LF diets, DFM inclusion resulted in increased BWG compared to the non-DFM treatments. Cumulative feed conversion ratio (FCR) was improved in HF treatments and the LF with DFM treatment compared to the LF with no DFM. In both trials, as expected, feeding HF diets resulted in increased AMEn. However, the DFM inclusion resulted in a greater uplift in AMEn in LF diets for both broilers and turkeys. In either trial, diet did not impact cecal VFA concentrations; thus, the impact on DFM on VFA production remains uncertain. In conclusion, the performance of broiler chicks and turkey poults was improved by DFM inclusion in reduced fat diets which was associated with increased energy digestibility as measured by AMEn.

Convergence of the turkey gut microbiota following cohabitation under commercial settings

BackgroundMicrobiota development is a critical aspect of turkey poult maturation, and the succession of microbes in the turkey gut has been shown to correlate with poult performance. The purpose of this study was to determine the fate of the microbiota in turkey poults after movement of birds first raised in an isolated hatch brood system into a more traditional commercial brood facility with pre-existing birds. Turkey poults were first divided into groups raised in conventional brood pens from day-of-hatch and those raised in an experimental hatch brood system. After 11 days of growth, hatch brood birds were moved into pens within the conventional brood barn and monitored for an additional 18 days. Sampling of both hatch brood and conventional pen birds was performed at multiple timepoints throughout the study, and cecal content was used to analyze the bacterial microbiota using 16S rRNA gene amplicon sequencing.ResultsAlpha diversity tended to be higher in samples from conventional pen birds compared to those from hatch brood birds prior to the day 11 move, but the difference between systems was not observed post-move. Using beta diversity metrics, bacterial community succession appeared delayed in the hatch brood system birds pre-move, but post-move community composition quickly converged with that of the conventional pen birds. This was validated through assessment of significantly different genera between hatch brood system and conventional pen birds, where numbers of significantly different taxa quickly decreased following the move. Some key taxa previously associated with poult performance were delayed in their appearance and relative abundance in hatch brood birds.ConclusionsOverall, this study demonstrates that the use of isolated hatch brood systems has an impact on the poult gut microbiota, but its impact is resolved quickly once the birds are introduced into a conventional brood environment. Therefore, the benefits of pathogen reduction with hatch brood systems may outweigh negative microbiota impacts due to isolation.

High doses of phytase on growth performance, bone mineralization, diet utilization, and plasmatic myo-inositol of turkey poults

An experiment was conducted to evaluate the growth performance, bone mineral composition, diet utilization, and plasmatic concentration of myo-inositol (MYO) in turkeys fed different phytase doses from 1 to 28 d. A total of three hundred and twenty 1-day-old turkeys were distributed in a completely randomized design with 4 treatments and 8 replicates of 10 birds each. Treatments included a basal diet without phytase; reduced diet (reduced −0.15% available P and −0.18% Ca) without phytase; reduced diet + 2,000 units of phytase (FYT)/kg; and reduced diet + 4,000 FYT/kg. From day 26 to 28, partial excreta collection was conducted, and on day 28, 7 birds per replicate were euthanized for collection of ileal content and left tibia bones were removed from 2 of the same euthanized birds. Feed, excreta, and ileal digesta samples were analyzed to determine nutrient digestibility and metabolizability, ileal digestible energy, and AME. Tibia bones were analyzed for ash, Ca, and P content, and calculation of Seedor index. On day 28, blood samples were collected from 2 turkeys per replicate to analyze plasmatic MYO concentration. Feed conversion ratio was not affected, but phytase supplementation resulted in higher feed intake and body weight gain compared to turkeys fed the reduced diet (P < 0.05), and both doses were similar to the basal diet. Increasing the phytase dose had a linear effect (P < 0.05) on ileal digestibility of P and metabolizability of DM, CP, Ca, and Na, and also on AME. P content in the tibia bone increased linearly (P < 0.05) with phytase supplementation, and the same linear increase (P < 0.05) was observed for plasmatic MYO. In conclusion, the supplementation of turkey poult's diets with high levels of phytase up to 4,000 FYT/kg improves diet utilization by increasing P digestibility and dietary metabolizability, leading to higher P content in the bone and enhancing MYO provision and absorption.

Growth performance, nutrient digestibility, carcass and economic characteristics of turkey poults fed millet-based diets as a replacement for maize

A nine (9) weeks feeding trial was conducted on seventy two (72) day-old Indigenous turkey poults raised on deep litter to determine their growth performance, carcass and economic characteristics when fed three dietary treatments (T1, T2, and T3, containing 0%, 25% and 50% replacement of maize with millet respectively. The birds were divided into three replicates of 8 birds per replicate; making a total of 24 birds per treatment. At the end of the &amp; week, 4 birds per replicate were transferred to specially-designed metabolism cages for a digestibility study involving the collection of faecal droppings; while at the end of the week of the experiments, two birds per replicate were randomly selected and slaughtered to determine their carcass characteristics. Turkey poults fed millet at 25 %replacement showed significantly (p&lt;0.05) higher body weight gain, lower cost of feed per kg live weight gain and higher revenue generated per bird; but there were no significant (p&gt;0.05) differences in the performance of birds on 0% and 50 % replacements for those parameters. Also, there were no significant (p&gt;0.05) differences in feed intake and mortality across the treatments. Similarly, there were no significant (p&gt;0.05) differences in nutrient digestibilities and carcass characteristics of the birds among the various dietary treatments. Therefore, it can be concluded hat millet cam be used to replace maize up to S0 % in the diets of turkey poults at the starter phase with no detrimental effects on their performance

Effects of alphamune G on the performance, serum and haematological parameters of Escherichia coli challenged turkey poults

A study was conducted to determine the response of Turkey poults to graded levels of Alphamune G (0.00+, 0.03, 0.04, 0.05, 0.06 and 0.00 %-) when challenged with Escherichia coli orally for 7 days. The graded levels were the treatments viz 0.00%+ (positive control), Alphamune G at 0.03, 0.04, 0.05, 0.06% and 0.00%- (negative control; infected without Alphamune G supplementation). Each treatment was allotted 3 replicates of 6 poults. The experiment which was conducted for 56 days employed a completely randomized design. E. coli was isolated from the intestinal digesta of a colisepticaemic chicken. 108 turkey poults were used in this study. Poults were infected with E.coli for 7 days through the drinking water and given the treatment. The performance parameters of Alphamune G supplementation were significantly affected. The cumulative weight, Feed intake and weight gain were highest for turkey poults fed 0.06% Alphamune G supplementation. These values were also directly proportional to the supplementation levels of Alphamune G. The birds given the negative treatment (0.00 %-) had relatively poor performance compared to the other treatments. The specific enzymes studied were significantly affected (p&lt;0.05) by the treatments. ALT and AST were significantly highest for turkey poults fed the negative control. Enzyme values became optimum at 0.05% Alphamune G supplementation. At 0.06% of Alphamune G supplementation, cellular mitigations of the effects of E. coli was measurable. Urea and creatinine were not significantly (p&gt;0.05) influenced by the treatments. Haematological indices such as WBC and specific differential counts (lymphocytes and neutrophils) were affected significantly (P&lt;0.05) by supplemental levels of Alphamune G The Inclusion of Alphamune G at 0.06% in the diets improved performance of turkey poults when challenged with Escherichia coli.

Effect of feed form, soybean meal protein content, and Rovabio Advance on poult live performance to 3 wk of age

Based on research reports, feed characteristics can increase poult growth via several factors. Two rearing experiments (EXP) were conducted to test the effects of feed form and ingredient quality in turkey poults. Bird performance and the duodenum, jejunum, ileum, and cecum morphology were observed in both EXP. Poults were reared in battery cages (48 cages in EXP 1 and 72 cages in EXP 2). Four dietary treatments with differing feed form and function factors were evaluated in EXP 1. A completely randomized block design with a 2 × 2 × 2 factorial arrangement of treatments consisting of 2 levels of fines, 2 soybean meal (SBM) sources, and 2 levels of an enzyme cocktail (Rovabio Advance) was tested in EXP 2. Poult BW, BW gain (BWG), feed intake (FI), and feed conversion ratio (FCR) were determined in both EXP. Apparent metabolizable energy corrected for nitrogen (AMEn) was determined in EXP 2. Differences were considered to be statistically significant at P ≤ 0.05. Feeding increased feed crumble particle size with fewer fines in the starter feed resulted in an increased BWG accompanied by an increased FI. Reduced feed fines reduced AMEn when the dietary enzyme cocktail was not present. The feed formulation with 60% CP SBM resulted in a lower FI and an improved FCR. The enzyme cocktail interacted synergistically with screening and fed SBM source factors on the AMEn and FCR. It was concluded that both the feed form and quality, as used in this study, affect poult performance.

Evaluation of a phytogenic feed additive on performance, nutrient digestion, and absorption in turkey poults

The objective of this experiment was to determine the effects of a phytogenic feed additive on turkey poult performance over a 6-week brooding period. A total of 864 male Hybrid Converter turkey poults were placed into pens that were randomly assigned one of three experimental groups. The three experimental diets included a corn-soy diet with no additives (PC), a similar diet with a 1.5 % reduction in crude protein and key amino acids (NC), and the same NC diet with Digestarom® (PFA) included at a rate of 1 g/kg. Performance-based experimental units (EU) consisted of one pen of 24 poults, with 12 EU per treatment. Mortality were recorded daily, and feed intake (FI), mortality corrected feed efficiency (FE), and body weight gain (BWG) were determined on days 14, 28, and 42. Samples were taken on days 28 and 42 to determine the coefficient of apparent crude protein digestibility (CPD). The expression of genes was determined for selected enzymes and nutrient transporters. The PFA improved poult BWG beyond that of the PC and NC on day 14 (263.7 vs. 252.5 and 252.7 g/bird, respectively; P ≤ 0.05), and there were no differences in FE (P > 0.05). On day 28, BWG was similar among treatments, although the PC had the highest FE (P < 0.01). The birds fed the PFA and PC diets had greater BWG on day 42 compared to the NC (2,447, 2,460, and 2,364 g/bird, respectively; P ≤ 0.01), and the PC had the highest FE (P ≤ 0.01). No differences were observed in the mRNA expression of EAAT3, PepT1, SGLT1, GLUT5, trypsin, amylase, or lipase. On day 42, the birds fed the PFA had lower ileal aminopeptidase activity (8.08 U/g total protein) compared to the NC (10.25 U/g total protein), while the PC was intermediate (8.58 U/g total protein), suggesting the PFA may be improving protein utilization (P = 0.05). Therefore, by the end of the experiment the PFA improved poult BWG to that of the PC; however, it had minimal effect on FE and nutrient digestion parameters.

Effect of a direct-fed microbial and prebiotic on performance and intestinal histomorophology of turkey poults challenged with Salmonella and Campylobacter

Salmonella and Campylobacter are leading human foodborne pathogens commonly associated with poultry and poultry products, and several methods to control these pathogens have been applied to poultry production. This study was conducted to evaluate the effect of CALSPORIN, (CSP), a direct-fed microbial (DFM), and yeast cell wall (Saccharomyces cervisiae, IMW50, a mannanoligosaccharide (MOS)-based prebiotic, on performance, levels of Salmonella and Campylobacter in the feces, and intestinal histomorphometry in turkey poults. A 21-day battery cage study was conducted using 4 dietary treatments, including: an unsupplemented basal diet (corn and soybean-based) as negative control (NC); basal diet supplemented with 0.05% DFM; basal diet supplemented with 0.05% MOS; and basal diet supplemented with 0.05% mixture of DFM and MOS at equal proportions. Female Large White turkey poults (n = 336) were randomly distributed in 6 electrically-heated battery cages with 4 treatments and 12 replicates per treatment (7 poults per replicate pen). The first 16 pens were not inoculated with bacteria, while poults in pens 17 to 32 were orally challenged at day 7 with 105 CFU Salmonella Heidelberg and the poults in pens 33 to 48 were orally challenged at day 7 with 105 CFU Campylobacter jejuni. Feed consumption, body weight, and feed conversion ratio were measured weekly and at the end of the experiment. At day 21, fresh fecal samples from each pen were collected for Salmonella and Campylobacter enumeration and ileal tissue samples were collected from 1 bird per pen for histomorphology examination. DFM and MOS supplementation was accompanied with reduced levels of Salmonella shed by the treated birds compared to the control group, and with increased body weight (P ≤ 0.05). The surface area of villi increased in the MOS-supplemented group compared to the control group (P ≤ 0.05). There was a significant difference in V:C ratio between supplemented groups and control group (P ≤ 0.05). Based on these results, there is potential for CALSPORIN and IMW50 to reduce Salmonella shedding in feces, enhance ileal mucosal health, and improve growth performance of turkey poults.

Effect of protein sources on performance characteristics of turkeys in the first three weeks of life.

The effect of nutrition during the early life of turkey poults has a long-lasting impact on bird performance. This study assessed the digestibility of 5 high protein feed ingredients (soybean meal [SBM], corn gluten meal [CGM], canola protein concentrate [CPC], fish meal [FM], and porcine meal [PCM]) in broiler chickens, as well as their use in turkey pre-starter diets fed to 21 d of age. The first experiment (5 × 2 factorial arrangement) determined nitrogen corrected apparent metabolizable energy (AMEn) and apparent ileal amino acid digestibility (AIAAD) of each ingredient in broiler chickens at 5 and 21 d of age, using 6 replications of 30 and 8 chicks, respectively. In the second experiment (completely randomized design), 4 replication pens, containing 23 d-old poults, were randomly assigned to one of 5 dietary treatments. The diets were formulated based on the AMEn and AIAAD values derived in the first experiment, and consisted of a high SBM control diet, and 4 additional diets with either CPC, FM, PCM or CGM replacing 25% of the protein supplied by SBM in the control diet. Statistical analysis was completed using Proc Mixed in SAS 9.3. Planned contrasts were used to compare treatments in the second experiment. Trends were identified at P < 0.10 and significant differences identified at P ≤ 0.05. Bird age did not affect CPC, FM, CGM, and SBM AMEn, but the PCM value at d 5 was higher than that at d 21. Apparent ileal amino acid digestibility increased with age for most amino acids (AA), but the response was AA and protein source dependent. The largest average increase in AIAAD between 5 and 21 d of age was observed for CGM. Inclusion of CPC, FM, PCM, or CGM increased body weight up to 14 d, in comparison to poults fed the SBM diet, but feed efficiency and water consumption were not affected. Terminal ileum digesta moisture values were higher for birds fed SBM when compared to those fed PCM. These results demonstrate that combining SBM with CPC, FM, PCM, or CGM improves poult performance during the first 14 d of life in comparison to feeding SBM alone.

Effects of carbon dioxide on turkey poult performance and behavior.

Appropriate ventilation of poultry facilities is critical for achieving optimum performance. Ventilation promotes good air exchange to remove harmful gases, excessive heat, moisture, and particulate matter. In a turkey brooder barn, carbon dioxide (CO2) may be present at higher levels during the winter due to reduced ventilation rates to maintain high temperatures. This higher CO2 may negatively affect turkey poult performance. Therefore, the objective of this study was to evaluate the effects of subjecting tom turkey poults (commercial Large White Hybrid Converters) to different constant levels of atmospheric CO2 on their growth performance and behavior. In three consecutive replicate trials, a total of 552 poults were weighed post-hatch and randomly placed in 3 environmental control chambers, with 60 (Trial 1) and 62 (Trials 2 and 3) poults housed per chamber. They were reared with standard temperature and humidity levels for 3 wks. The poults were exposed to 3 different fixed CO2 concentrations of 2,000, 4,000, and 6,000 ppm throughout each trial. Following each trial (replicate), the CO2 treatments were switched and assigned to a different chamber in order to expose each treatment to each chamber. At the end of each trial, all poults were sent to a local turkey producer to finish growout. For each trial, individual body weight and group feed intake were measured, and mortality and behavioral movement were recorded. Wk 3 and cumulative body weight gain of poults housed at 2,000 ppm CO2 was greater (P < 0.05) than those exposed to 4,000 and 6,000 ppm CO2. Feed intake and feed conversion were unaffected by the different CO2 concentrations. No significant difference in poult mortality was found between treatments. In addition, no effect of CO2 treatments was evident in the incidence of spontaneous turkey cardiomyopathy for turkeys processed at 19 wk of age. Poults housed at the lower CO2 level (2,000 ppm) demonstrated reduced movement compared with those exposed to the 2 higher CO2 concentrations.

Effect of stocking density vis-à-vis dietary protein supply on growth performance, immune-competence and cost economics of growing turkey poults

A 10-week biological experiment was undertaken to evaluate the response of Beltsvilie Small White turkey poults to different floor space (0.6, 0.8, and 1.0 ft2/bird) and dietary protein levels (22%, 24% and 26% with similar dietary energy) in terms of growth performance, immune response, and serum biochemistry, following 3 × 3 factorial design. Each treatment was allocated 4 replicates out of which one replicate was maintained for the replacement of the dead birds, if any, to maintain the required stocking density. The body weight gain (BWG), feed intake (FI) and performance index (PI) of poults was significantly higher in 1.0 ft2 floor space during 0–4 weeks and 4–10 weeks of age. Similarly, higher BWG, FI, and PI were observed at 26% dietary protein level. The interaction effect between stocking density and protein levels during 0–4 week resulted in significantly higher FI at 0.8 ft2 floor space with 26% protein level and 1.0 ft2 floor space with 24% as well as 26% protein level. The feed conversion ratio (FCR), mortality pattern, immune response and immune organ weights of poults did not reveal any significant treatment effect. The feed cost/bird increased linearly with increasing floor space, and feed cost/kg weight gain and feed cost/ kg meat increased linearly with increasing protein levels. However, profit potential per meter square decreased linearly with decreasing stocking density. The study concluded that increasing the stocking density and decreasing the dietary protein level decrease the performance of poults, but the profit potential per meter square increases with increasing stocking density. Thus, the study recommends either the floor space of 0.8 ft2/bird with 26% dietary protein level or the floor space of 1.0 sq2/bird with 24% dietary protein level for growing turkey poults.

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.

Effects of yeast fermentation product inclusion during the brooder phase and grower/finisher phase feed form effects on large tom performance using feed produced at a commercial mill

SUMMARY The brooder phase (d one to 42) is crucial to overall turkey performance, and many integrators believe that the utilization of yeast products (YP) is cost effective. Pellet quality is crucial to grower/finisher phase production (d 42 to 118) due to feed form advantages during this period of high-volume consumption. Also, feed and feed manufacture represent the largest investment required to produce poultry. The objective of this study was to establish the effects of YP (YP1 or YP2) inclusion on d one to 42 poult performance. On d 42, a 2 YP carryover x 2 feed form [intact high-quality pellets (HQP) or ground pellets (GP)] factorial arrangement was used to measure main effects and interactions on d one to 118 tom performance. All diets had similar nutrient composition (other than YP), and feed was manufactured at a commercial feed mill. Feed form consisted of either intact HQP (average of 21.4% fines) or ground HQP (GP; average particle size of 1,108 microns). Male Hybrid Converters were reared at a facility that mimicked commercial grow-out. On d 42, YP1 improved ending weight (EW) and FCR. No YP carryover effect was demonstrated for any of the d 42 to 118 performance variables. Feeding HQP produced toms that were 0.29 kg/bird heavier with 9 points lower FCR, as compared to toms fed GP. Regression analyses predicted that if toms fed GP finished at the same d 118 EW as those fed HQP, then FCR advantages of HQP would be 12 points. These FCR benefits may justify the increased feed costs associated with manufacturing HQP.