Heavy Broilers Research Articles

Technical and economic performance favours fully automated climate control broiler housing

ABSTRACT 1. This study compared two broiler housing models with different technologies (conventional versus fully automated climate control) to verify their performance and carcass characteristics at slaughter, as well as the economics of production. 2. A database regarding 20 443 flocks of heavy broilers produced in an integrated operation during the years 2020 and 2021, in eight Brazilian regions was used in the analysis. The dependent variables included feed conversion, average live weight gain, total and partial carcass condemnation and the total mortality. For economic analysis, the production cost of each technology including feed, labour, energy, heating and depreciation was calculated. 3. The technology used in the broiler houses had a significant effect on the technical indicators which were positive for fully automated climate control in most geographical regions. One important exception was the effect on total and partial carcass condemnations, with better results seen for conventional housing. The total cost per ton of broiler meat delivered, deducting condemnation losses, was lower in the automated climate controlled housing compared to conventional housing. 4. In conclusion, there was a reduction in broiler chicken production costs for birds raised in fully automated climate controlled housing, indicating better economic results for this model in Brazil.

Pharmacokinetic modeling of sulfamethoxazole-trimethoprim and sulfadiazine-trimethoprim combinations in broilers

Sulfonamides (S) are old bacteriostatic antibiotics which are widely prescribed in combination with trimethoprim (TMP) for the treatment of various diseases in food-producing animals such as poultry. Nowadays, the 1:5 dose ratio of TMP/S used in broilers is a direct transposition of the ratio determined in Human decades ago for TMP/sulfamethoxazole (SMX), aiming to obtain a supposed synergistic plasma concentration ratio of 1:19. However, major pharmacokinetics (PK) differences exist according to the sulfonamide used in the combination. Here, we generated new PK data in broilers after a cross-over design with IV and the oral administration of 2 major sulfonamides, sulfadiazine (SDZ) and SMX, in combination with TMP, and analyzed the data via a population pharmacokinetic (popPK) modeling approach. Results showed that TMP has a greater plasma to tissue distribution than both sulfonamides with a higher volume of distribution (0.51 L/kg for SDZ, 0.62 L/kg for SMX and 3.14 L/kg for TMP). SMX has the highest elimination half-life (2.83 h) followed by SDZ and TMP (2.01 h and 1.49 h, respectively). The oral bioavailability of the 3 molecules was approximately 100%. Bodyweight could explain some of the inter-individual variability in the volume of distribution of SDZ and SMX and the clearance of SDZ and TMP, as heavier broilers have higher typical values. Monte Carlo simulations of a large virtual broiler population (n = 1,000) showed that the targeted plasma ratio of TMP:S of 1:19 was rarely or never reached at the individual level for both combinations at the marketed doses and greatly varies over time and between individuals, questioning the relevance of the 1:5 dose ratio for current formulations of TMP/S.

Measurement of Dynamic Electric Consumption Trend in a Broiler House in Arkansas

Highlights We quantified the diurnal and seasonal electric load pattern during four consecutive growouts of heavy broilers over an 11-month period on a commercial farm. Consumption was measured separately for ventilation fans, lights, feed motors, well pump motors and radiant tube heater blowers. Ventilation fans were the largest consumer of energy and the largest contributor to peak demand on the farm. Average monthly electric demand ranged from 31% to 77% of the corresponding monthly peak demand, calculated from the largest 15-min period. The electricity cost of raising heavier-weight broiler chickens is higher in the summer ($22 per 1,000 kg live weight) than in the winter ($5 per 1,000 kg live weight). Abstract. Characterizing electric energy use in a commercial broiler house—partitioned by bird age, season, and electric load type—can provide engineers with insight for designing energy conservation practices, as well as help to analyze and design on-site renewable energy production sub-systems. This study monitored electric energy consumption in a commercial broiler house in Arkansas, raising heavy broilers (with a capacity of 17,000 birds) during an 11-month period that included four, 8-week flocks. Average electricity use (RMS voltage and current) was measured at a sampling interval of 5 min for all of the major load types, including ventilation, lighting, feed motors, and well-water pump motor. Results indicated that electric consumption for ventilation fans was the greatest load, accounting for over 88% of the total. The endwall fans (for tunnel ventilation) contributed to the peak electric demand (VA) in nine of the 11 months. Over the 11-month monitoring period, broiler chicken production had an average electric energy consumption (per unit live-weight mass produced) of 43 kWh per metric ton of live weight (in a winter flock) to 184 kWh per metric ton (in a summer flock). The corresponding electric costs were $5 per metric ton and $22 per metric ton in winter and summer flocks, respectively (based upon an electricity unit cost of $0.12/kWh). Keywords: Electricity demand, Energy efficiency, Poultry housing.

Effects of a Sprinkler and Cool Cell Combined System on Cooling Water Usage, Litter Moisture, and Indoor Environment of Broiler Houses.

Climate change is a serious challenge to food production around the world. Sustainability and water efficiency are critical to a poultry industry faced with global production concerns including increased demands for high-quality, affordable animal protein and greater environmental pressures resulting from rising global temperatures, flock heat stress, and limits on water availability. To address these concerns, a commercial sprinkler system used in combination with a cool cell system was evaluated against a cool cell system alone for two summer flocks of heavy broilers at Mississippi State University to determine effects of sprinkler technology on cooling water usage, litter moisture, and in-house environments. Environmental data were calculated and recorded throughout the flocks. The combination house exhibited a 2.2 °C (4 °F) increase in daily maximum temperature, lower coincident relative humidity, and a 64% (62,039 L/flock) reduction in average cooling water usage over the cool cell-only house. Litter moisture for the combination house tended to be numerically lower but showed no significant difference at several time points between and across flocks. A combined sprinkler/cool cell system reduced cooling water use by 64% over two flocks compared to a cool cell alone system and decreased in-house relative humidity levels.

Effect of Dietary Enrichment with Flaxseed, Vitamin E and Selenium, and of Market Class on the Broiler Breast Meat-Part 2: Technological and Sensorial Traits.

The influence of diet enrichment with flaxseed, selenium and vitamin E, and market class on breast meat was investigated in terms of technological and sensorial quality of breast meat. A randomized complete block design with an experimental unit of n = 6000 broilers receiving a standard or enriched diet, and slaughtered at 37 (light class), 47 (medium class), or 57 (heavy class) days of life, was developed. Then, enriched and standard breast muscles from every market class were studied for their technological and sensorial traits—both at 24 h post-mortem and after one month of frozen storage—by a statistical multiple linear model. Redness and yellowness of muscles significantly (p < 0.05) increased and decreased with increasing market age. Moreover, the yellowness significantly (p < 0.05) raised after frozen storage. However, obtained data were always indicative of a normal meat color. The water holding capacity improved following fed enrichment and significantly (p < 0.05) worsened after frozen storage. For the sensory analysis, juiciness and chewing rest of meat resulted significantly (p < 0.05) improved with increasing slaughtering age and diet enrichment, as well as their mutual interaction, while they deteriorated after frozen storage. Overall, fresh and enriched muscles from heavy broilers had the best technological and sensorial traits, thus, confirming that market size and diet should be highly considered to obtain breast meat with greater consumer acceptance.

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.

Impacts of Air Velocity Treatments under Summer Conditions: Part II—Heavy Broiler’s Behavioral Response

Simple SummaryBehavioral changes are one of the mechanisms for broilers to adjust their body temperature under heat stress conditions. However, the behavioral responses of heavy broilers to environmental changes have not yet been studied well. Therefore, this research investigated the behavioral changes of broilers under two dynamic air velocity treatments (high and low) under summer conditions. Video data collected from a heat stress experiment conducted on broilers aged 42–54 days were used to investigate variations in the number of chickens feeding, drinking, standing, walking, sitting, wing flapping, and leg stretching. The results indicated that the high air velocity treatments increased the number of chickens feeding, standing, and walking. In addition, age significantly affected the number of birds feeding, drinking, panting, and sitting, while the time of the day also affected the number of chickens drinking and panting. This study reveals the thermal stress of heavy broilers from their behavior under summer conditions to help manage the performance and welfare of birds under environmental stress.Broiler chickens exposed to heat stress adapt to various behavioral changes to regulate their comfortable body temperature, which is critical to ensure their performance and welfare. Hence, assessing various behavioral responses in birds when they are subjected to environmental changes can be essential for assessing their welfare under heat-stressed conditions. This study aimed to evaluate the effect of two air velocity (AV) treatments on heavy broilers’ behavioral changes from 43 to 54 days under summer conditions. Two AV treatments (high and low) were applied in six poultry growth chambers with three chambers per treatment and 44 COBB broilers per chamber from 28 to 61 days in the summer of 2019. Three video cameras placed inside each chamber (2.44 m × 2.44 m × 2.44 m in dimension) were used to record the behavior of different undisturbed birds, such as feeding, drinking, resting, standing, walking, panting, etc. The results indicate that the number of chickens feeding, drinking, standing, walking, sitting, wing flapping, and leg stretching changed under AV treatments. High AV increased the number of chickens feeding, standing, and walking. Moreover, a two-way interaction with age and the time of day can affect drinking and panting. This study provides insights into heavy broilers’ behavioral changes under heat-stressed conditions and AV treatments, which will help guide management practices to improve birds’ performance and welfare under commercial conditions in the future.

Impacts of Air Velocity Treatments under Summer Condition: Part I-Heavy Broiler's Surface Temperature Response.

Simple SummaryThe surface temperature variation of heavy broilers (42–61 d age) under heat stress is an important indicator of thermal comfort, but it is not well studied and reported yet. This study examined the variation of surface temperatures of broilers through two dynamic air velocity treatments under hot summer conditions. It was discovered that the surface temperatures varied over age, daytime, and environmental factors (air temperature, relative humidity, and temperature humidity index). A simple linear regression model to predict the surface temperature of heavy broilers was developed. The findings from this study will enhance knowledge to understand the broilers’ responses under heat stress, which will be helpful in providing necessary management decisions to create a comfortable thermal environment.Heavy broilers exposed to hot summer conditions experience fluctuations in surface temperatures due to heat stress, which leads to decreased performance. Maintaining a bird’s homeostasis depends on several environmental factors (temperature, relative humidity, and air velocity). It is important to understand the responses of birds to environmental factors and the amount of heat loss to the surrounding environment to create thermal comfort for the heavy broilers for improved performances and welfare. This study investigates the variation in surface temperatures of heavy broilers under high and low air velocity treatments. Daytime, age and bird location’s effect on the surface temperature variation was also examined. The experiment was carried out in the poultry engineering laboratory of North Carolina State University during summers of 2017, 2018, and 2019 as a part of a comprehensive study on the effectiveness of wind chill application to mitigate heat stress on heavy broilers. This live broiler heat stress experiment was conducted under two dynamic air velocity treatments (high and low) with three chambers per treatment and 44 birds per chamber. Surface temperatures of the birds were recorded periodically through the experimental treatment cycles (flocks, 35–61 d) with infrared thermography in the morning, noon, evening, and nighttime. The overall mean surface temperature of the broilers under two treatments was found to be 35.89 ± 2.37 °C. The variation in surface temperature happened due to air temperature, thermal index, air velocity, bird’s age, daytime, and position of birds inside the experimental chambers. The surface temperatures were found lower under high air velocity treatment and higher under low air velocity treatment. During the afternoon time, the broilers’ surface temperatures were higher than other times of the day. It was also found that the birds’ surface temperature increased with age and temperature humidity indices. Based upon the experimental data of five flocks, a simple linear regression model was developed to predict surface temperature from the birds’ age, thermal indices, and air velocity. It will help assess heavy broilers’ thermal comfort under heat stress, which is essential to provide a comfortable environment for them.

Corn kernel hardness, drying temperature and amylase supplementation affect live performance and nutrient utilization of broilers

Drying temperature (DT) of corn can influence its nutritional quality, but whether this is influenced by endosperm hardness is not clear. Two parallel experiments were conducted to investigate the effects of 2 yellow dent corn hybrids with average and hard kernel hardness, dried at 3 temperatures (35, 80, and 120°C), and 2 supplementation levels of an exogenous amylase (0, 133 g/ton of feed) on live performance, starch and protein digestibility, and energy utilization of Ross 708 male broilers. Twelve dietary treatments consisting of a 2 × 3 × 2 factorial arrangement were evaluated using 3-way ANOVA in a randomized complete block design. In Experiment 1, a total of 1,920 male-chicks were randomly allocated to 96 floor pens, whereas 480 day-old chicks were distributed among 96 cages for Experiment 2. At 40 d, interaction effects (P < 0.05) were detected on BWG, FCR, and flock uniformity. Supplementation with exogenous amylase resulted in heavier broilers, better FCR and flock uniformity, only in the diets based on corn dried at 35°C. Additionally, interaction effects were observed on FCR due to kernel hardness and DT (P < 0.01), kernel hardness and amylase supplementation (P < 0.001), and DT and amylase supplementation (P < 0.05). Exogenous amylase addition to the diets based on corn with an average hardness improved FCR up to 2 points (1.49 vs. 1.51 g:g) whereas there was no effect of amylase on FCR of broilers fed diets based on corn with hard endosperm. Total tract retention of starch was increased (P < 0.05) in broilers fed diets based on corn with average kernel hardness compared to hard kernel. Corn dried at 80 and 120°C had up to 1.21% points less starch total tract retention than the one dried at 35°C. Supplementing alpha-amylase resulted in beneficial effects for broiler live performance, energy utilization, and starch total tract digestibility results. Treatment effects on starch characteristics were explored. Corn endosperm hardness, DT and exogenous amylase can influence the live performance of broilers. However, these factors are not independent and so must be manipulated strategically to improve broiler performance.

A review on the woody breast condition, detection methods, and product utilization in the contemporary poultry industry.

In recent years, the global poultry industry has been facing increasing and challenging myopathies such as the woody breast (WB) condition that has caused significant economic losses. Even though the etiological causes of WB myopathy are still unknown or partially understood, the intensive genetic selection for rapid-growth rates and high yields in broilers may be the main factor associated with the development of this abnormality. The severity of this anomaly and its incidence rates are associated with fast-growing and heavier broilers, especially with those from high breast yielding strains. Such WB myopathy is primarily characterized by a notorious hardness in broiler breast muscles, which exhibit morphometric and histopathological alterations coupled with physicochemical abnormalities that result in undesired sensory, nutritional, and technological properties. In this negative context, although scientists are trying to solve or reduce the prevalence of this meat quality problem, the poultry industry needs noncontact and rapid in-line methods for WB detection at the fillet and/or carcass level that could help to establish automated objective grading or sorting systems according to its severity. Another need is the development and selection of profitable alternatives for the utilization of WB meat once poultry carcasses or deboned fillets affected by this abnormality are objectively detected and sorted. Indeed, there is a need for studies to expand the industrial applications of WB meat in further processed products, optimizing the incorporation of this affected chicken meat based on sensorial, technological, and nutritional profile evaluations. Even though a better understanding of the contribution of genetic and nongenetic factors to the development of growth-related myopathies can be the main strategy to mitigate their negative effects, the poultry industry could benefit from meeting the aforementioned needs.

FATTY ACID CONTAINMENT IN ORGANIC CHICKEN-BROILERS MEAT AND TRADITIONAL GROWING

The article presents the results of the study on fatty acids content of broiler chickens purchased from retailers and broiler chickens grown in organic farming. In the study we compared the obtained results. There are also results of the influence of developed preventive drug postbiotic on the fatty acid composition of broiler chickens. The samples were compared in terms of their nutritional value and quality. Chicken that goes into the retail network is obtained from broiler chickens grown in a traditional (intensive) technological way. Organic poultry is extensive. For the experiment in organic farming, we formed the 2 groups (control and experiment). In the experimental group, broiler chickens received a prophylactic preparation - a postbiotic with organic feed, and no drugs were used in the control. In-depth studies of the mechanisms of its effect on the body of chickens and the quality of the products obtained were studied changes in the fatty acid composition of total lipids in skeletal muscle and the biochemical composition of the muscle tissue of chickens. There were no significant changes in the fatty acid content of the tested meat compared with the control group. The content of palmitoleic, linoleic and caprylic acids is slightly increased. The fat content of heavy broiler chickens is much higher than that of broiler chickens. The best fatty acid ratio of omega-3 and omega-6 is found in organic chicken meat. Retail chicken meat has a lower omega 6 content, significantly higher than palmitic acid omega 3. Organic chicken meat contains 3-5% less fat compared to retail chicken. In the meat of chickens grown using organic technology, the amount of saturated fatty acids increased significantly by 11.13%, there is a significant decrease in omega-6 fatty acids by 7.57% and an increase in the amount of omega-3 fatty acids by 0.8% compared to with chicken from the retail chain. Therefore, the value of organic chicken meat lies not only in the absence of residues of antibiotic substances, pesticides and herbicides, but also in its biological value and dietary properties.

Effects of amino acid and energy density on growth performance and processing yield of mixed-sex Cobb 700 × MV broiler chickens

Summary The overall cost of feed is influenced largely by the nutritional requirements that are specified in its formulation and the ingredients that are used to meet those nutrient specifications. To meet the demand for breast meat and further processed products, heavy broiler chickens are grown to body weights exceeding 3.5 kg. In this study, we evaluated the effects of altering AA density and AME content of the diets over the last 3 feeding phases (grower: 12–26 D, finisher: 26–36 D, and withdrawal: 36–49 D) on the growth performance and processing yield of mixed-sex Cobb 700 × MV broilers. Broilers were fed a common starter diet followed by a 3 × 2 factorial arrangement of diets with 3 levels of AA density (low, medium, and high) and 2 levels of energy (low and high) beginning with the grower period. Broilers fed the high AA diet were heavier as compared with those fed the low AA diet, and FCR was observed to decrease incrementally when AA density and energy level were increased independently. Skinless-boneless breast yield increased incrementally with AA density, whereas fat pad yield increased as AA density of the diet decreased. Overall, our results demonstrate that the performance and meat yield of mixed-sex Cobb 700 × MV broilers responded positively to a higher density of AA and energy.

Absolute expressions of hypoxia-inducible factor-1 alpha (HIF1A) transcript and the associated genes in chicken skeletal muscle with white striping and wooden breast myopathies

Development of white striping (WS) and wooden breast (WB) in broiler breast meat have been linked to hypoxia, but their etiologies are not fully understood. This study aimed at investigating absolute expression of hypoxia-inducible factor-1 alpha subunit (HIF1A) and genes involved in stress responses and muscle repair using a droplet digital polymerase chain reaction. Total RNA was isolated from pectoralis major collected from male 6-week-old medium (carcass weight ≤ 2.5 kg) and heavy (carcass weight > 2.5 kg) broilers. Samples were classified as “non-defective” (n = 4), “medium-WS” (n = 6), “heavy-WS” (n = 7) and “heavy-WS+WB” (n = 3) based on abnormality scores. The HIF1A transcript was up-regulated in all of the abnormal groups. Transcript abundances of genes encoding 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 4 (PFKFB4), lactate dehydrogenase-A (LDHA), and phosphorylase kinase beta subunit (PHKB) were increased in heavy-WS but decreased in heavy-WS+WB. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was up-regulated in non-defective samples. The muscle-specific mu-2 isoform of glutathione S-transferases (GSTM2) was up-regulated in the abnormal samples, particularly in the heavy groups. The genes encoding myogenic differentiation (MYOD1) and myosin light chain kinase (MYLK) exhibited similar expression pattern, of which medium-WS and heavy-WS significantly increased compared to non-defective whereas expression in heavy-WS+WB was not different from either non-defective or WS-affected group. The greatest and the lowest levels of calpain-3 (CAPN3) and delta-sarcoglycan (SCGD) were observed in heavy-WS and heavy-WS+WB, respectively. Based on micrographs, the abnormal muscles primarily comprised fibers with cross-sectional areas ranging from 2,000 to 3,000 μm2. Despite induced glycolysis at the transcriptional level, lower stored glycogen in the abnormal muscles corresponded with the reduced lactate and higher pH within their meats. The findings support hypoxia within the abnormal breasts, potentially associated with oversized muscle fibers. Between WS and WB, divergent glucose metabolism, cellular detoxification and myoregeneration at the transcriptional level could be anticipated.

Effect of Broiler Slaughter Weight on Meat Yield and Quality

Broiler meat quality depends on the interaction of several factors, including genotype, slaughter age/body weight, pre-slaughter handling, and slaughter method. The aim of this study was to determine the effect of slaughter weight on meat yield and quality of broilers. The material consisted of 42 broilers, classified into three groups: lighter ( 3000 g). The following meat yield parameters were measured: cold carcass weight, breast weight before and after deboning, breast skin and bone weights, thigh weight before and after deboning, thigh skin and bone weights, drumstick weight before and after deboning, and drumstick skin and bone weights. Meat pH (M. pectoralis major) and instrumental colour (breast and drumstick) were measured 24 h post-mortem. Meat quality classes (pale, soft and exudative and normal meat) were determined based on breast muscle L* value. Heavier broilers had higher (P 0.05) affected by slaughter weight. In conclusion, production of heavy broilers had a beneficial effect on meat quantity, while the effect of slaughter weight on meat quality was negligible.

Effect of high dietary levels of α-tocopherol acetate on immune response of light and heavy weight male broiler breeders

The objective of this study was to investigate the effect of overdosing dietary α-tocopherol acetate (α-TOH) on immune response of heavy weight roosters. A total of 60 roosters (Ross 308) of light (LW, n = 30) and heavy weight (HW, n = 30) were kept in individual cages. Roosters were randomly allotted to ten treatment groups in a 2 × 5 factorial design. Each group received a basal diet supplemented with graded levels of α-TOH (0, 100, 200, 300, 400 mg/kg diet) for 10 weeks (from 25 to 35 week of age). Blood samples were collected at the fifth and tenth weeks of the experiment. Afterwards, humoral immune system function was evaluated by sheep red blood cell (SRBC) hemagglutination assay (HA) (at 35 weeks of age) and hemagglutination inhibition (HI) tests including antibody response to Newcastle disease viruses (NDV) and avian influenza viruses (AIV) (at 30 and 35 weeks of age). Cell-mediated immune response was evaluated by the cutaneous basophil hypersensitivity (CBH) test. A positive linear relationship was observed between incremental levels of dietary α-TOH and both humoral and cell-mediated immunity (P ≤ 0.05), with the highest immune parameters recorded for dietary supplementation of 400 mg/kg α-TOH (P ≤ 0.05). The results showed that CBH was significantly higher in LW roosters in comparison with HW roosters (P ≤ 0.05). However, the interaction of BW and α-TOH doses did not have any significant effect on immune responses (P ≥ 0.05). In conclusion, dietary supplementation of α-TOH at higher levels (four times more than the strain nutrients recommendation) had beneficial effects on the immune response of both HW and LW male broiler breeders.

Influence of light sources and photoperiod on growth performance, carcass characteristics, and health indices of broilers grown to heavy weights

Effects of light sources and photoperiod on growth performance, carcass characteristics and health indices of broilers were investigated in 4 trials. In each trial, 720 1-day-old Ross × Ross 708 chicks were randomly distributed into 12 environmentally controlled rooms (30 males/30 females/room). The experimental design was a 4 × 3 factorial treatments consisted of 4 light sources [incandescent (ICD, standard), compact fluorescent (CFL), neutral light-emitting diode (Neutral-LED), and cool poultry-specific filtered LED (Cool-PSF-LED)] and 3 photoperiods [long/continuous (23L:1D), regular/intermittent (2L:2D), and short/non-intermittent (8L:16D)] from d8-d56. Birds were fed the same diet, while feed and water were provided ad libitum. Birds and feed were weighed on 1, 14, 28, 42, and 56 d of age for growth performance. Mortality was recorded daily and feed conversion was adjusted for mortality. Immune response was determined on d 28 to 35, whereas other welfare indices were performed on d 42, 43, and 49. At 56 d of age, 10 male and 10 female birds from each room were randomly selected and processed to determine weights and yields. The BW, BW gain, live weight, and carcass weights and yields of birds reared under Cool-PSF-LED were increased (P ≤ 0.05) in comparison to birds reared under ICD, but FI, FCR, and mortality were not affected. Moreover, broilers subjected to the short/non-intermittent photoperiod had the lowest (P ≤ 0.05) BW, BW gain, FI, live weight, carcass weight, and pectoralis major and minor weights compared to other 2 photoperiods. There was no effect of treatments on some carcass characteristics. There was no effect of treatments on welfare indices, suggesting that the light sources evaluated did not compromise welfare of heavy broilers. It was concluded that the 3 light sources evaluated in this study may be suitable for replacement of ICD light source along with regular/intermittent photoperiod instead of long/continuous photoperiod in poultry facilities to save energy utilization, thereby reducing the total cost of production.

Economic losses associated with Wooden Breast and White Striping in broilers

Currently, two defects in poultry breasts termed Wooden Breast (WB) and White Striping (WS) have been reported in slaughterhouses. These defects may be associated with the accelerated growth of the birds, management, density in the aviary, and both weight and age at slaughter. Although the health of the affected birds is not impaired, these myopathies cause carcass condemnation and economic losses to slaughterhouses, since the breasts of these chickens, considered to be prime cuts in the poultry industry, have to be discarded. This paper reports on the economic losses and factors associated with carcass condemnation caused by white striping (WS) and wooden breast (WB) in broilers from a federally inspected slaughterhouse. Twelve flocks, totaling 207,000 slaughtered broilers, were assessed as to weight and age at slaughter, and stocking density and carcass condemnations due to these two myopathies were also evaluated. Economic losses were estimated by the price of poultry breast at the firm level, around U$ 19,12 per kilo, amounting to daily losses of up to U$ 70,632.00, given that approximately 0.8% of the chicken breasts were condemned. Heavier broilers had a larger condemnation rate due to WS and WB, and so did those reared at a smaller density, due probably to their better access to water and feed, which contributed to weight gain and consequent condemnation, resulting in losses that could affect the entire poultry sector.

Effects of different floor housing systems on the welfare of fast-growing broilers with an extended fattening period

Abstract. This study was made to investigate the long-term effects of different floor housing systems on the welfare of fast-growing broilers. The experiment was performed on 210-day-old fast-growing hybrid male chickens with identical conditions until 47 days of age. Animal-based welfare parameters were measured to investigate the welfare level in the group housed on deep litter, a litter and slat system, and a slatted floor, with five replicates for each group. Results showed that the main welfare indicators in live birds, such breast dirtiness, plumage score, footpad lesion, and hock burn lesion, were negatively affected in broilers kept on conventional deep-litter floor housing. But hemorrhage or lesion scores of the breast and shoulder of broilers in slat floor housing were found to be significantly greater than in conventional deep litter as a result of a heavy body weight at a greater slaughter age (p&lt;0.05). Pathologically, the prevalence of footpad and hock joint dermatitis was very high in the deep-litter housing system. Femoral head necrosis was not observed in any floor housing group. The results indicated that keeping broilers on a slat flooring system is preferable for younger slaughter ages and for a lighter slaughter weight. When considering the relationship between animal welfare and production economy, moving from one floor house system to another floor housing system should be carefully weighted in future decisions. Moreover, further investigations are needed in order to examine the incidence of joint and bone problems with muscle inflammation in heavier broilers in commercial conditions.

Environmental impact assessment of an Italian vertically integrated broiler system through a Life Cycle approach

Poultry meat represents one of the most popular meat products in the world and its production is expected to increase significantly in the next decades. The Italian broiler sector is characterized by a vertically integrated intensive production system and a high final weight of broilers in comparison to the other European countries. The Life Cycle Assessment method was used to estimate environmental impacts (Global Warming Potential; Acidification; Eutrophication; Terrestrial ecotoxicity; Non-renewable fossil energy) of 1 kg of broiler carcass weight at slaughterhouse gate in an Italian integrated broiler group. Moreover, the effects of final live weight and stocking density on the impacts were studied. Broiler fattening resulted the most impactful phase for all the impact categories, contributing on average for 87% of impacts. Conversely, the hatchery, breeder rearing and slaughtering phases moderately concurred to impact categories. Heavy broilers (roasters) showed the higher impacts per kg live weight compared to light and medium live weight broilers mainly due to the worse feed conversion ratio. The main contribution to environmental impacts in the fattening phase was feed production and processing; in particular purchased protein feeds, mainly soybean meal, were the greatest single contributor to all impact categories. The reduction of final live weight of Italian broilers from 2.6 kg to 1.6 kg could lower the total Global Warming Potential of the Italian broiler sector by about 12%. In the scenario analysis the increasing stocking density up to the maximum allowed determined only slight effects on the environmental impacts per kg carcass weight.

Effects of light sources and intensity on broilers grown to heavy weights. Part 1: Growth performance, carcass characteristics, and welfare indices

This study investigated the effects of light sources and light intensity on growth performance, carcass characteristics, and welfare indices of heavy broilers (>3.0 kg) in 4 trials with 2 replications per trial. A total of 960 one-day-old Ross×Ross 708 chicks (30 males/30 females/room) were randomly distributed into 16 environmentally controlled rooms at 50% RH. A 4×2 factorial treatment structure evaluated 4 light sources (incandescent [ICD, standard], compact fluorescent [CFL], neutral light emitting diode [Neutral-LED], and cool poultry specific filtered LED [Cool-PSF-LED]) and 2 levels (5 lx, 20 lx) of light intensities. Each of the 4 light sources was paired with one of the 2 light intensities. Birds were fed the same diet with a 4-phase feeding program (starter, grower, finisher, and withdrawal). Feed and water were provided ad libitum. Birds and feed were weighed on one, 14, 21, 28, 42, and 56 d of age for growth performance. All mortality was recorded daily and feed conversion was adjusted for mortality. Immune response was determined on d 28 to d 35, whereas other welfare indices were performed on d 42 and 49, respectively. At d 56 of each trial, 20 (10 males and 10 females) birds from each room were processed to determine weights and yields. The BW, BW gain, live weight, and carcass weights of birds reared under Cool-PSF-LED were different (P≤0.05) in comparison to birds reared under ICD. However, FI, FCR, and mortality were not affected by treatments. There was no effect of treatments on fat or breast and tender weights and yields. In addition, there was no effect of treatments on ocular development, immune response, and other welfare indices, suggesting that the light sources evaluated did not compromise welfare of heavy broilers. It was concluded that the 3 light sources evaluated in this study may be suitable for replacement of ICD light source in poultry facilities to reduce energy cost and optimize production efficiency.