Breast Weight Research Articles

Influence of diet formulation technique on requirement of digestible lysine for growing Japanese quail: A practical reflection

This work aimed to investigate the influence of two diet formulation techniques: supplementation and dilution, on estimates of digestible lysine requirements in growing Japanese quail. For this, 492 Japanese quails (10 to 36 days old) with initial weight of 33.7 ± 0.42 g were used, housed in overlapping cages, and distributed in a completely randomized design in a 2 × 5 factorial arrangement. Two formulation techniques (supplementation technique and dilution technique) and five levels of lysine (0.80; 0.90; 1.00; 1.10 and 1.20%) were used, thus composing 10 treatments and 6 repetitions with 8 birds each. Performance parameters, nutrient gain, and carcass components were evaluated. There was interaction (p <0.05) between the formulation techniques and the levels of digestible lysine tested for feed intake, weight gain, protein gain, fat gain, chilled carcass weight, breast weight and thigh percentage, in addition to the isolated effect of the formulation technique on feed conversion, and isolated effect of the levels of digestible lysine on feed conversion and thigh weight. The digestible lysine requirement values estimated for better performance and efficiency in nutrient deposition were 1.028% or 133 mg/day by the supplementation technique, and 1.063% or 140 mg/day by the dilution technique. It can be concluded that the requirement for digestible lysine in Japanese quail is influenced by the formulation technique, and the supplementation technique had better results.

Carcass and meat quality of red-winged tinamou (Rhynchotus rufescens) selected for muscle growth

The aim of the present study was to evaluate the efficiency of selection for body growth and its association with carcass and meat quality traits in the red-winged tinamou. Two experimental groups were selected based on the selection index: selection group with a higher index (TinamouS) and commercial group with a lower index (TinamouC). Weight at 180 days and slaughter weight were significantly higher (p < 0.05) in the TinamouS group, as were hot carcass weight, skinless breast weight, wing weight, and thigh and drumstick weight. The meat quality traits or sensory attributes did not differ significantly (p > 0.05) between groups. A significant positive correlation (0.59; p < 0.05) was found between shear force and chewability and a significant negative correlation (- 0.59; p < 0.05) between aroma intensity and strange aroma. The present study suggests that the selection index promotes greater body growth and preserves meat quality and sensory traits in red-winged tinamou.

Sous-vide cooking as a practical strategy to improve quality attributes and shelf stability of reduced-salt chicken breast ham

The objective of this study was to evaluate the general quality attributes and shelf stability of reduced-salt and sous-vide cooked chicken breast hams during 4 weeks of refrigerated storage (4°C). Four treatment groups of chicken breast ham were prepared using a 2 (salt level, 1.5% NaCl (regular) and 0.75% (reduced))×2 (cooking method, conventional and sous-vide) factorial arrangement. Based on each chicken breast weight, 20% NaCl solution was injected. Conventional cooking was done at 80°C until the core temperature reached 71°C, whereas sous-vide cooking was conducted at 60°C for 2 h. Sous-vide cooking could decrease cooking loss and shear force of reduced-salt chicken breast ham (P < 0.05). As a result, sensory scores for juiciness and tenderness of reduced-salt and sous-vide cooked chicken breast ham were similar to those of regular-salt and conventionally cooked chicken breast hams (P > 0.05). No adverse impacts on lipid oxidation and microbial safety were found in reduced-salt and sous-vide cooked chicken breast ham during 4 wk of refrigerated storage. Therefore, this study suggests that sous-vide cooking could be a practical thermal process for improving the water-holding capacity and texture of chicken breast ham without adverse impacts on shelf stability. Further studies on the combined application of sous-vide cooking with salt replacers would be warranted to improve the sensorial acceptance of saltiness of sous-vide cooked low-salt meat products.

Epigenetic effects of selenium and vitamin E supplementation in broiler breeder diets on the performance of their progeny

Nutritional supplements have been commonly used in the poultry industry last few years. The study aimed to investigate the epigenetic effects of adding vitamin E and organic selenium to the diet of broiler breeders Ross-308 on their progeny meat production performance. The treatments included the control group fed with a standard diet without supplementation (T1), T2 using a standard diet supplemented with 500 mg of vitamin E / kg, T3 using a standard diet supplemented with 0.5 mg of organic selenium (Availa powder) /kg, and T4 using a standard diet supplemented with a mixture of vitamin E and organic selenium in proportions 500 and 0.5 mg/kg respectively. The eggs were collected from each treatment to obtain the progeny reared for 35 periods, and measurements were recorded for meat production and carcass traits. The results showed that the treatments had significant epigenetic effects on body weight at hatching. Hence, T2 had a significantly heavier body weight than T1, while no significant differences were observed between T3 and T4. The result of T2 recorded extremely high feed intake compared with T3. On the other hand, T3 and T4 recorded a hefty weight of breast parts compared with T1 and T2. In conclusion, organic selenium supplementation led to a significant increase in breast weight and a decrease in thigh part weight compared to the control group. In contrast, vitamin E supplementation led to an increase in chick weight at hatch, a reduction of total mortality and an improvement in feed conversion ratio compared to the control group. This refers to the epigenetic effects of organic selenium and vitamin E on progeny traits when added to the breeder diet. Keywords: Epigenetics, broiler, selenium supplementation, meat production

Effects of soybean meal replacement byHermetia illucens larvae meal on growth performance, meat quality and gastrointestinal health in broilers

The growing demand for broilers production is related to environmental and economic impacts worldwide, increasing the urgency to find alternative feed ingredients. Recent studies indicated the productive potential of some insect species, which may serve as a protein and lipid source for animal feeding, as the case of black soldier fly (BSF) larvae (Hermetia illucens). This study aimed at assessing the effects of dietary replacement of soybean meal by BSF larvae meal in broiler diets, in growth parameters, liver and intestinal tract morphology, carcass and meat quality. Forty-eight 1-day old chicks (Ross 308) were randomly assigned to one of four feeding regimes, which consisted of a basal diet in which soybean meal was replaced BSF larvae meal, at levels of 0% (Hi0), 25% (Hi25), 50% (Hi50) and 75% (Hi75). The animals’ excreta were collected and registered daily, and half the animals were slaughtered at 28 days of age. The liver, caecum and other portions of the intestines were analysed, and the intestinal tract was collected for histopathological analysis. BSF larvae meal did not affect carcass weight, but it resulted in a lower weight of the right breast of birds when fed with a 75% inclusion level (P=0.049). In addition, all growth parameters, general meat quality and excreta production were similar among treatments, while excreta characteristics were significantly different (P&lt;0.05). Dietary BSF meal resulted in lower liver weight (P=0.03) in comparison to the control. No histopathological lesions were found in the gastrointestinal tract and morphometric traits were similar among treatments. It was concluded that the dietary inclusion of BSF larvae meal for broilers did not significantly affect the animals’ growth and gut health. This alternative feed ingredient can be used as a more sustainable option for broilers at up to 75% of soybean meal replacement.

Influence of Dietary Protease on Growth Performance and Carcass Yield of Indian River Meat Broiler Chickens

The aim of the present study was to evaluate the effect of a multi-component dietary protease complex on the growth performance and carcass yields of commercial broiler chickens. A total of 630 Indian River broiler DOCs were considered and assigned to five dietary treatments namely: 1) Positive control (PC), a standard diet with no supplemental protease, 2) Negative control (NC), a diet similar to PC but reduced in CP, digestible EAA, and ME based on supplier’s nutrient matrix recommendation, 3) PC+125 ppm protease (PC+125), 4) NC+125 ppm protease (NC+125), and 5) NC+200 ppm protease (NC+200). The birds were fed experimental diets for 28 days. Body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR), and survival rate were recorded weekly. On day 28, three birds per treatment were sacrificed for carcass yield analysis. FI was similar among the treatment groups except in the 2nd week where broilers fed PC+125, NC+125, and NC+200 diets had significantly higher (P&lt;0.05) FI than those fed the PC diet. In terms of BW and BWG, there were no differences among the treatment groups at 1st and 2nd weeks, however, at 3rd and 4th weeks, broilers fed the PC+125, NC+125, and NC+200 diets were significantly heavier (P&lt;0.05) than those fed the PC and NC diets. A similar trend was also observed in FCR. Among the carcass yield parameters, the percentage weights of thigh, breast, and heart in birds fed the NC+200 diet were significantly increased (P&lt;0.05) as compared to those fed the NC diet, while results for PC, PC+125, and NC+125 were intermediate between the two treatment groups. Overall, the results of present study demonstrated that the supplementation of protease complex either on a standard or reduced diet may improve the overall production performance of commercial broiler chickens and offers benefits on certain aspects of carcass yield.

Blood Profile and Carcass Production of Broiler Chickens Given Nucleotides and Turmeric Extract in Feed

Broiler chickens are birds that grow very fast, but have low body resistance and are easily stressed. This study aimed to examine the effect of nucleotide and turmeric extract (Curcuma longa Linn) on blood profile (erythrocytes, hemoglobin and leukocytes) and carcass production (weight of carcass, weight of breast, thighs and wings) in broiler chickens. Data was collected using a completely randomized design with 7 treatments consisting of Control: basal feed + antibiotic Bacitracin Zinc 0.1 g/day; N 0 : basal feed; N 1 : basal feed + turmeric extract 600 mg/kg feed; N 2 : basal feed + nucleotide 250 mg/kg feed; N 3 : basal feed + nucleotide 250 mg/kg feed + turmeric extract 600 mg/kg feed; N 4 : basal feed + nucleotide 500 mg/kg feed; N 5 : basal feed + nucleotide 500 mg/kg feed + turmeric extract 600 mg/kg feed. The results showed that nucleotide supplementation and turmeric extract had no significant effect on weight of carcass, weight of breast, thighs and wings, hemoglobin, erythrocytes and leukocytes of broiler. The use of nucleotide and turmeric extract could not improve the blood profile of broiler.

Pengaruh Tepung Kulit Buah Naga Merah (Hylocereus polyrhizus) terhadap Potongan Komersial Karkas Ayam Broiler

This research was conducted to determine the effect of red dragon fruit peel meal on the weight and percentage of carcass, lower thigh, upper thigh, wing, breast, and back of broiler carcass. This research used a Completely Randomized Design (CRD) with 4 treatments and each treatment had 6 replications. The treatments were T0 = basal diet (BD) without dragon fruit peel meal (DPM), T1 = BD+0.5% DPM, T2 = BD+1% DPM and T3 = BD+1.5% DPM. The parameter were final weight, carcass weight and percentage, commercial cuts of carcass weight and percentage. The results of this study showed that the red dragon fruit (Hylocereus polyrhizus) peel meal in broiler chicken diet had no significantly effect on the final weight, carcass weight and percentage, and commercial cuts of carcass weight and percentage of broiler chicken. The diet with red dragon fruit peel meal up to 1.5% have no negative effect to broiler chickens.

Rearing broilers as mixed or single-sex: relevance to performance, coefficient of variation, and flock uniformity

With known variation in performance between male and female broilers and the fact that sourcing single-sex birds for use in research is becoming increasingly difficult, it becomes important to determine the effect of rearing method with male and female broilers on between-pen variation and body weight (BW) uniformity. We evaluated the performance response of broilers reared as single or mixed-sex to standard and reduced crude protein (CP) diets. The study was designed as a 2 × 3 factorial arrangement of treatments consisting of 672 Cobb-500 broilers assigned to 48 floor pens with 6 treatments, 8 replicates, and 14 birds per pen. The factors were rearing method (male single-sex, female single-sex, or equally mixed-sex) and dietary CP level (standard or reduced). For the overall period of the trial (d 0–35) there was a significant effect (P < 0.001) of rearing method and CP level on feed intake (FI) and feed conversion ratio (FCR). There was also a significant interaction between rearing method and CP level for BWG during d 0 to 35 (P < 0.01). There was a significant interaction between CP level and sex on d 34 BW (P < 0.01) where the reduced CP diet decreased the BW of both males and females, but to a greater extent the BW of the female birds. Dietary CP level had a significant effect on relative breast and drumstick weights with birds fed the reduced CP diet having significantly lower breast weights (P < 0.001) and higher drumstick weights (P < 0.01).This study suggests that male and female broilers have different CP requirements, and rearing birds as equally mixed-sex results in the lowest CV% for performance parameters and best BW uniformity compared to single-sex birds. Furthermore, when low CP diets are fed to broilers, they will prioritize the growth of more important body parts such as the legs.

Processing weights of chickens determined by dual-energy X-ray absorptiometry: 1. Weight changes due to fasting, bleeding, and chilling

The increasing breast weight of modern broilers highlights the convenience of studying the dynamics of processing weights across the grow-out period. For models predicting these traits to work with non-fasted live birds under longitudinal studies, it is necessary to determine the changes in the weights of birds due to fasting and bleeding and carcasses due to chilling. This study aimed to develop a model to predict the fasting weight loss of broilers, determine the weight changes due to bleeding and chilling, and assess the percentage of gizzard fat in the abdominal fat. Models were fitted to fasting BW loss data from literature. A bleeding BW loss value obtained in a pilot study was compared to literature. This one and a single-source percent gizzard in the abdominal fat value were used as reference values. Birds from two experiments were selected at different ages to determine the following variables: non-fasted and fasted BW, bled weight, unchilled and chilled carcass weights, and gizzard fat and abdominal fat pad weights. Predicted and reference values were compared to the observed data based on their 95% confidence intervals, and the fitted model and reference values were validated if no statistical differences were inferred. The fasting BW loss model was refitted to the data from experiments, and the estimates of the model fitted to both datasets were compared. The fasting BW loss followed a three-parameter exponential model with reducing values as the bird aged, and the predicted and observed values showed no statistical difference (P > 0.05). The reference bleeding BW loss (2.76%) and gizzard fat percentage (18%) values showed no difference (P > 0.05) to data from broiler experiments, and a chilling carcass weight gain of 2.79% was determined. The scale and relative growth rate estimates of the fasting BW loss model showed no difference (P > 0.05) between datasets, and the asymptote showed a possible but negligible difference. The fasting BW loss model, the bleeding BW loss coefficient, and the gizzard fat percentage were validated. The model and coefficients obtained herein will not only be applied to predict processing weights using Dual-Energy X-ray Absorptiometry but also may be used in other modeling approaches.

The Optimum Ratio of Digestible Leucine: Lysine in Wheat-based Diets for Female Broiler Chickens From 8 – 21 Days of Age

Leucine ( Leu ) is one of the essential amino acids, and has a direct effect on protein biosynthesis in broiler skeletal muscle. So supply of sufficient amounts of Leu in young broiler is of interest. Therefore, the purpose of the current study was to estimate the optimal digestible Leu in ratio to lysine ( Lys ) of female broiler chickens from 8 – 21 days. A dose-response trial was performed, and the optimal digestible Leu was estimated applying broken-lines and quadratic regression models. A total of 540 one-week-old female broiler chickens (Cobb-500), were randomly distributed to 6 dietary treatments (6 replicate of 15 birds in each), and fed the experimental diets from 8 to 21 day of age. Dietary digestible Leu was supplied from 0.93% up to 1.18% in 0.05% increments. Wheat-soybean meal based diet was formulated to be deficient in Leu, and dietary treatments were created by gradually replacing crystalline L-glutamic acid with crystalline L-Leu in basal diet. The live performance and carcass traits were evaluated, and excretion and retention of nitrogen was measured. The results showed that weight gain ( WG ), feed intake ( FI ), carcass weight and breast weight had a quadratically response to digestible Leu: Lys from 0.93 to 1.18. Also, none of the retention and excretion of nitrogen were affected by increasing dietary digestible Leu levels. Based on the obtained data in the current study, the optimal digestible Leu: Lys of female Cobb 500 broilers fed with wheat-based diets from 8 to 21 days of age was estimated between 0.99 and 1.12 with an average of 1.06 based on quadratic broken-line model as the concluded value.

Carcase characteristics, meat quality, nutrient composition, serum biochemistry and oxidant/antioxidant status in white striping-affected broiler chickens fed diets based on maize-soybean meal

ABSTRACT 1. Effects of the incidence of white striping (WS) in relation to carcase weights and yields, breast meat quality and composition, serum biochemistry and oxidant/antioxidant status of breast meat in broiler chickens were investigated. 2. The study consisted of 180, one-d-old male broiler chickens fed maize-soybean meal-based starter, grower, finisher and withdrawal diets identical to commercial chicken diets. On d 49, all the birds were slaughtered and breast fillets were visually scored for the incidence of WS. Breast meat and blood samples were collected and categorised based on the presence or absence of WS. 3. The study revealed greater slaughter weight, carcase and breast fillet weights and yields, lower pHu and higher cooking loss of breast meat with WS lesions (P < 0.05). WS-affected breast fillets had greater fat and lower crude protein contents in comparison with normal meat (P < 0.001). Serum creatine kinase levels were greater in broilers with WS (P = 0.011), whereas oxidant/antioxidant status of breast meat remained unaffected. 4. Taken together, the presence of WS on breast muscle altered the quality and nutrient composition of breast fillets and serum creatine kinase levels in broiler chickens fed diets based on maize-soybean meal. Nevertheless, WS was more common in heavier broilers having higher breast weight and yield.

Severidad de miopatías de pechuga y su relación con indicadores de bienestar productivos, fisiológicos y de comportamiento en pollos de engorde

The objective of the experiment was to evaluate the relationship between different degrees of severity of the myopathies known as wooden breast and white stretch marks with physiological, productive and behavioral indicators of well-being. 570 Ross 308 broilers, reared under commercial conditions for 13 weeks, were used. From week 7 to 13, prior to slaughter, the breast of 35 chickens was randomly palpated, according to their consistency and classified as soft, intermediate and firm. Fifteen blood samples were taken from the 35 chickens to obtain the heterophil-lymphocyte ratio, C-reactive protein, and the hematological profile. Group ethograms were performed by direct observation, weekly. Live weight, breast weight, hot carcass weight, and cold carcass weight were recorded. Each breast was classified according to the degree of severity of the lesions of the white streaks and the wooden breast as normal, mild, moderate and severe. The processed breasts were palpated and classified as soft, medium and firm. Each one was measured for force and shear energy. The results showed that the physiological indicators were not related to the severity of the lesions found for both myopathies. Injury severity increased and was significantly associated with age, live weight, and breast weight. Live chicken breast palpation was highly correlated with processed breast palpation, so live palpation can be used as a noninvasive indicator of consistency and severity of lesions in both myopathies. It is required to evaluate more physiological, behavioral and pain indicators in chickens that present white streaks and wooden breast.

Bıldırcın Diyetlerine Farklı Düzeylerde Nar Çekirdeği Yağı İlavesinin Besi Performansı ve Karkas Özelliklerine Etkisi

Bu çalışma, besiye alınan bıldırcınların diyetlerine ilave edilen farklı düzeylerdeki (%0, 0.5, 1, 1.5 ve 2) nar (Thymbra spicata L. var. spicata) çekirdeği yağının bıldırcınların besi performansları ve karkas özellikleri üzerine etkisini araştırmak amacıyla yapılmıştır. Çalışmada, günlük yaşta 135 adet Japon bıldırcını civcivi kullanılmış olup, hayvanlar 42 gün süreyle besi denemesine alınmışlardır. Çalışmada, kontrol ve muamele gruplarına ait bıldırcınlarda, canlı ağırlık, yem tüketimi, yemden yararlanma oranı, karkas ağırlığı ve karkas randımanlarına ait ortalamalar arasındaki farklılıkların istatistiksel olarak önemsiz olduğu saptanmıştır. Benzer şekilde, karkas kısımları ve iç organlara ait ortalamalar bakımından, göğüs ağırlığı, kanat ağırlığı, boyun ağırlığı, karaciğer ağırlığı, kalp ağırlığı ve testis ağırlığı arasındaki farklılıklar da önemsiz bulunmuştur. Ancak, but ağırlığı bakımından dişiler arasındaki farklılıklar önemli olmuştur (P

Factors Affecting Breast Myopathies in Broiler Chickens and Quality of Defective Meat: A Meta-Analysis.

Fast-growing broiler chickens are subjected to breast myopathies such as white striping (WS), wooden breast (WB), and spaghetti meat (SM). Available studies about risk factors for myopathy occurrence often used flock data whereas a few reports evaluated chicken individual data. Thus, the present study aimed to elucidate the effect of growth and slaughter traits, besides sex and genotype on myopathy occurrence. Data were obtained from eight experimental trials, which used a total of 6,036 broiler chickens. Sex, genotype, daily weight gain, slaughter weight, and breast yield were evaluated as potential risk factors by logistic regression analyses. Then, the effects of myopathy and sex were evaluated on meat rheological traits (pH, colour, cooking losses and shear force). Based on a logistic regression, WS occurrence was associated with genotype, breast weight, and breast yield. Compared with chickens with intermediate breast weight and breast yield, higher odds of having WS were found in chickens with high breast weight (OR: 1.49) and yield (OR: 1.27), whereas lower odds were found in those with low breast weight (OR: 0.57) and yield (OR: 0.82). As for WB and SM, females had lower odds of having WB (OR: 0.55) and higher odds of showing SM (OR: 15.4) compared to males. In males, higher odds of having WB were found in chickens with a high daily weight gain (OR: 1.75) compared to those with an intermediate daily weight gain. In females, higher odds of having SM were associated to a high slaughter weight (OR: 2.10) while lower odds to a low slaughter weight (OR: 0.87). As for meat quality, only WB meat was clearly different for some technological and sensorial properties, which can play a major role also in meat processing. In conclusion, our analysis identified breast development as a potential risk factor for WS, while a high growth was the risk factor for WB and SM. A different probability of having WB or SM in females and male was found.

Evaluation of cassava distillers’ waste meal in the diet of Broiler Chicken

This study was designed to examine the growth properties, nutrient retention, blood components and carcass cuts of broiler chicken fed cassava distillers’ waste meal (CDWM) in place of maize. A total of three hundred (300) day old Abor-Acre strain chicks were stochastically assigned to five groups using completely randomized design at 60 birds each replicated thrice. The CDWM was included in the diets at 25, 50, 75, and 100% at the expense of maize in the control diet. Cassava distillers’ waste meal had a high protein and fibre content compared to maize. Significant differences (p&lt;0.05) were observed in the growth parameters, nutrient digestibility, packed cell volume and breast weight. The final weight and daily gain reduced as CDWM increased in the diet while average daily feed consumed and conversion ratio increased linearly; birds offered control diet had the lowest and best feed conversion ratio while those fed the 100% replacement had the highest feed conversion ratio. Thus, the optimal inclusion level of CDWM in broiler diets should not exceed 25% as a replacement for maize. Further study is required to determine if the addition of multi-carbohydrase enzyme will encourage higher replacement level of maize with CDWM in broiler diet.

Using TD-NMR relaxometry to assess the effects of diet type and stocking rate on the incidence and degree of severity of myopathies in broilers

This study aimed to evaluate different feeding strategies and stocking rates (SR) on the occurrence and severity of broiler myopathies. Additionally, a second aim was to test the potential use of Time-Domain Nuclear Magnetic Resonance (TD-NMR) relaxometry for assessing white striping (WS) and wooden breast (WB) incidence and the degree of severity in broiler chicken breasts. Treatments were arranged in a 2 × 2 factorial design and consisted of two nutritional levels (regular and superior diets) and two different SR (high 47 kg/m2 or regular 59 kg/m2). Infrared thermography (IRT) images were recorded on three different days to determine the average, minimum and maximum temperatures. After 49 days of rearing, birds were slaughtered, and 75 breasts were weighed and classified according to the absence (normal breast, without the occurrence of myopathy – NB) or occurrence and severity of WB and WS. The whole breasts were analysed by TD-NMR relaxometry using the Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence and Continuous Wave-Free Precession (CWFP-T1) pulse sequence. There was no effect of diet and diet*SR interaction on the weight of breast meat; however, chickens raised at the higher density presented a lower breast weight (P < 0.0001; 490 vs. 539 g). The incidence and severity of myopathies was not influenced by the treatments (P = 0.9467); the frequencies of WB and WS were similar in the different treatments. For CPMG and CWFP-T1, three and two relaxation populations were noted, respectively. The sPLS-DA model optimisation showed a significant separation between WS and NB in terms of occurrence and severity. In conclusion, changes in diet and SR did not mitigate the occurrence or severity of WS and WB. Additionally, TD-NMR relaxometry showed to be a promising technology for evaluating and segregating breasts according to myopathy incidence and severity.

Apparent metabolizable energy, growth performance and carcass traits of Japanese quail fed select modern grain sorghum varieties.

This study was performed to determine the apparent metabolizable energy (AMEn) content of tannin-free red/bronze, white/tan and U.S. No. 2 varieties of grain sorghum for feeding Japanese quail and validate their nutrient profile by evaluating effects on performance and carcass traits with full-substitution of corn. Experiment 1 determined the AMEn content of red/bronze, white/tan, and U.S. No. 2 grain sorghum varieties fed to mixed-sex Japanese quail (Coturnix japonica) (n = 314) at 3 and 6-weeks of age. Analyses were based on a 2×4 factorial treatment design with age and grain types defining the treatments, and a randomized complete block experiment design with cage and trials defining the block. AMEn values were validated by evaluating the performance and carcass traits of Japanese quail (n = 644) from 1 to 40 days of age in Experiment 2 with birds were fed 1 of 4 complete diets. Statistical analyses were conducted on performance data and select individual carcass trait measurements. Determined AMEn values at 3-weeks of age were 3,524±122.03 (red/bronze), 3,252±122.03 (white/tan), and 3,039±123.44 (U.S. No. 2) kcal/kg. At 6-weeks of age, determined AMEn were 3,373±297.35 (red/bronze), 3,279±297.35 (white/tan), and 2,966±298.64 (U.S. No. 2) kcal/kg. Carcass traits showed live body weight (p = 0.0409) and hot carcass weight (p = 0.0234) were greatest in U.S. No. 2; however, carcass yield (p<0.0001) was lowest. No significant differences were observed among treatments for feed intake, feed conversion ratio, breast weight and breast yield (p>0.05). These studies demonstrated that tannin-free grain sorghum varieties may be a potential alternative to corn in quail diets while maintaining growth performance and carcass parameters.

Effect of electron beam irradiated barley grains on growth performance, blood parameters, nutrient digestibility, microbial population, and intestinal histomorphometry in broiler chickens

ABSTRACT The aim of this study was to examine the effect of electron beam-irradiated barley on performance and some physiological parameters of broiler chicks. Treatments were barley (25% and 50% of diet, raw and irradiated at 40 kGy) and control diet that used with five dietary treatments in a completely randomized design. Irradiation decreased the negative effects of barley on weight gain during the entire production phases at the level of 50%. Relative weight of breast increased in birds fed 25% irradiated barley compared to those fed 50% barley (P < .05). The relative weight of the gizzard as well as the lengths of the duodenum, jejunum and ileum was higher (P < .05) in birds fed 50% raw barley compared to that of the other treatments. Broilers fed a 50% barley diet had lower (P < .05) cholesterol and triglycerides concentrations compared to the birds fed 25% barley. The ileal apparent digestibility of nutrients decreased in birds fed 50% barley compared to those fed 25% barley. The caecal population of Lactobacillus was decreased (P < .05) in broilers fed on 50% raw barley. It is concluded that electron irradiation seems to be an effective procedure to improve the performance parameters of broiler chickens when the birds are fed high levels of barley.

Internal organ and skeletal muscle development in commercial broilers with woody breast myopathy

Increasing growth rate, body weight, and breast muscle yield have been linked to broiler muscle problems such as woody breast (WB). The aim of this study was to investigate the internal organ and skeletal muscle development of broilers with WB myopathy under dietary and Eimeria challenge treatments. A 3 diet (control, antibiotic, or probiotic) × 2 challenge (control or Eimeria) × 2 sex factorial arrangement of treatments was used in a randomized complete block design. Ross × Ross 708 chicks were randomly assigned to 96 floor pens with 12 treatment combinations (8 replicates per treatment). Internal organs were sampled on d 13 and 41. Skeletal muscles were sampled on d 41. Internal organ and skeletal muscle weights were analyzed using a 3-way analysis of variance (ANOVA). Relationships between WB and internal organ and skeletal muscle weights were analyzed using one-way ANOVA as all treatments were pooled together and regrouped according to WB scores. On d 41, absolute and relative heart weights were greater in males when they were averaged over diet and challenge treatments (P < 0.001 and P = 0.026, respectively). The birds with WB score 3 had greater absolute heart (P = 0.0002) and spleen weights (P = 0.016), but there was no difference in relative spleen weight (P > 0.05). When averaged over diet and challenge treatments, males have greater absolute duodenum, jejunum, and ileum weights (for all P < 0.0001). Compared with birds with normal breasts, the birds with WB scores 1, 2, and 3 had a greater live weight (for all P < 0.0001) and absolute and relative breast weights (for all P < 0.0001). The birds with WB score 1, 2, and 3 had greater (P < 0.0001) absolute but lower (P < 0.0001) relative drumstick, thigh, and wing weights. Results indicated that broilers with WB had lower relative proventriculus and gizzard weights and greater relative breast meat weight with lower relative drumstick, thigh, and wing muscle weights.