Optimizing sheep growth curves using a meta-heuristic algorithm.

Sheep were among the first animals domesticated by humans, and to this day, small ruminants are primarily raised for their meat, milk, and wool. This study evaluated the goodness of fit for growth curve models using observed age and weight data from crossbred lambs of various breeds based on the mean values between paired breeds. We employed a hybrid metaheuristic algorithm, combining a simulated annealing (SA) algorithm and a genetic algorithm (GA) called SAGAC, to determine the optimal parameter values for growth models, ensuring the best alignment between simulated and observed curves. The goodness of fit and model accuracy was assessed using the coefficient of determination (R2), Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and Mean Absolute Percentage Error (MAPE). Errors were measured by comparing the criteria differences between simulated and observed data. Thirty crossbreed combinations were simulated, considering the average weight. Analysis of the observed and simulated growth curves indicated that specific crossbreeding scenarios produced promising results. This simulation approach is believed to assist geneticists in predicting potential crossbreeding outcomes, thereby saving time and financial resources in field research.

Sequential Behavior of Broiler Chickens in Enriched Environments under Varying Thermal Conditions Using the Generalized Sequential Pattern Algorithm: A Proof of Concept.

Behavior analysis is a widely used non-invasive tool in the practical production routine, as the animal acts as a biosensor capable of reflecting its degree of adaptation and discomfort to some environmental challenge. Conventional statistics use occurrence data for behavioral evaluation and well-being estimation, disregarding the temporal sequence of events. The Generalized Sequential Pattern (GSP) algorithm is a data mining method that identifies recurrent sequences that exceed a user-specified support threshold, the potential of which has not yet been investigated for broiler chickens in enriched environments. Enrichment aims to increase environmental complexity with promising effects on animal welfare, stimulating priority behaviors and potentially reducing the deleterious effects of heat stress. The objective here was to validate the application of the GSP algorithm to identify temporal correlations between heat stress and the behavior of broiler chickens in enriched environments through a proof of concept. Video image collection was carried out automatically for 48 continuous hours, analyzing a continuous period of seven hours, from 12:00 PM to 6:00 PM, during two consecutive days of tests for chickens housed in enriched and non-enriched environments under comfort and stress temperatures. Chickens at the comfort temperature showed high motivation to perform the behaviors of preening (P), foraging (F), lying down (Ld), eating (E), and walking (W); the sequences <{Ld,P}>; <{Ld,F}>; <{P,F,P}>; <{Ld,P,F}>; and <{E,W,F}> were the only ones observed in both treatments. All other sequential patterns (comfort and stress) were distinct, suggesting that environmental enrichment alters the behavioral pattern of broiler chickens. Heat stress drastically reduced the sequential patterns found at the 20% threshold level in the tested environments. The behavior of lying laterally "Ll" is a strong indicator of heat stress in broilers and was only frequent in the non-enriched environment, which may suggest that environmental enrichment provides the animal with better opportunities to adapt to stress-inducing challenges, such as heat.

Broiler behavior differs from males to females when under different light wavelengths.

It is well established that different light wavelengths affect broiler behavior. The present study aims to evaluate the effect of four light wavelengths on broiler behavior from 1 to 42 days of age. Birds were housed at a stocking density of 13 birds/m2, in 32 boxes of 1.56 m2. The experimental design was a completely randomized factorial of 4 × 2 (four colors × two sexes), with four replicates. Behavioral variables were accessed through cameras and observed in person thrice a week for 30 min per day in three different periods. Data were organized according to age groups and analyzed by a data mining approach with the different light wavelengths as the classes. Natural behavior defined by stretch, dust bath of male broilers reared in environments with green and blue light was more relevant to the classification of male broilers' behavior (96.9 and 96.9% accuracy and 0.8 and 1.0 of class precision of behavior classification, respectively). Blue and green lights affected the behavior of male broilers starting at 7 days of age, increasing the presence at the bird feeder, and reducing the idle period.

Computer-Vision-Based Indexes for Analyzing Broiler Response to Rearing Environment: A Proof of Concept.

Computer-vision systems for herd detection and monitoring are increasingly present in precision livestock. This technology provides insights into how environmental variations affect the group's movement pattern. We hypothesize that the cluster and unrest indexes based on computer vision (CV) can simultaneously assess the movement variation of reared broilers under different environmental conditions. The present study is a proof of principle and was carried out with twenty broilers (commercial strain Cobb®), housed in a controlled-environment chamber. The birds were divided into two groups, one housed in an enriched environment and the control. Both groups were subjected to thermal comfort conditions and heat stress. Image analysis of individual or group behavior is the basis for generating animal-monitoring indexes, capable of creating real-time alert systems, predicting welfare, health, environment, and production status. The results obtained in the experiment in a controlled environment allowed the validation of the simultaneous application of cluster and unrest indexes by monitoring the movement of the group of broilers under different environmental conditions. Observational results also suggest that research in more significant proportions should be carried out to evaluate the potential positive impact of environmental enrichment in poultry production. The complexity of the environment is a factor to be considered in creating alert systems for detecting heat stress in broiler production. In large groups, birds' movement and grouping patterns may differ; therefore, the CV system and indices will need to be recalibrated.

The environmental cost of broiler production and carbon sequestration potential of eucalyptus plantations around farms in Mato Grosso do Sul, Brazil.

The present study aimed to evaluate the environmental cost of the production process of broilers from the approach of emergy accounting and carbon sequestration potential for broiler farms. The study assessed a standard farm of the conventional system containing ten houses in 19 ha. We evaluated the following indices solar transformity (Tr), renewability (%R), emergy yield ratio (EYR), emergy investment ratio (EIR), environmental loading ratio (ELR), emergy sustainability index (ESI), and emergy exchange ratio (EER) and carbon sequestration potential of eucalyptus plantation. The total emergy input was 2.79E-06 seJ ha-1 y-1 for the broiler growth process. The highest investment in the production process was related to materials, which came from feeding and electricity. The renewability index indicated the low sustainability of the system with increased consumption of economical materials and equipment, with a low proportion of the emergy use of renewable resources. High investment in broilers production in the conventional system generates an environmental loading ratio that indicates high environmental degradation. Planting trees in the surrounding areas of the farm facilities can minimize the externalities of the production system with the plantation carbon sequestration potential.

Energy Assessment from Broiler Chicks' Vocalization Might Help Improve Welfare and Production.

Vocalization seems to be a viable source of signal for assessing broiler welfare. However, it may require an understanding of the birds' signals, both quantitatively and qualitatively. The delivery of calls with a specific set of acoustic features must be understood to assess the broiler's well-being. The present study aimed to analyze broiler chick vocalization through the sounds emitted during social isolation and understand what would be the flock size where the chicks present the smallest energy loss in vocalizing. The experiments were carried out during the first 3 days of growth, and during the trial, chicks received feed and water ad libitum. A total of 30 1-day-old chicks Cobb® breed were acquired at a commercial hatching unit. The birds were tested from 1 to 3 days old. A semi-anechoic chamber was used to record the vocalization with a unidirectional microphone connected to a digital recorder. We placed a group of 15 randomly chosen chicks inside the chamber and recorded the peeping sound, and the assessment was conducted four times with randomly chosen birds. We recorded the vocalization for 2 min and removed the birds sequentially stepwise until only one bird was left inside the semi-anechoic chamber. Each audio signal recorded during the 40 s was chosen randomly for signal extraction and analysis. Fast Fourier transform (FFT) was used to extract the acoustic features and the energy emitted during the vocalization. Using data mining, we compared three classification models to predict the rearing condition (classes distress and normal). The results show that birds' vocalization differed when isolated and in a group. Results also indicate that the energy spent in vocalizing varies depending on the size of the flock. When isolated, the chicks emit a high-intensity sound, "alarm call", which uses high energy. In contrast, they spent less energy when flocked in a group, indicating good well-being when the flock was 15 chicks. The weight of birds influenced the amount of signal energy. We also found that the most effective classifier model was the Random Forest, with an accuracy of 85.71%, kappa of 0.73, and cross-entropy of 0.2.

A Heuristic and Data Mining Model for Predicting Broiler House Environment Suitability.

The proper combination of environment and flock-based variables plays a critical role in broiler production. However, the housing environment control is mainly focused on temperature monitoring during the broiler growth process. The present study developed a novel predictive model to predict the broiler (Gallus gallus domesticus) rearing conditions' suitability using a data-mining process centered on flock-based and environmental variables. Data were recorded inside four commercial controlled environment broiler houses. The data analysis was conducted in three steps. First, we performed an exploratory and descriptive analysis of the environmental data. In the second step, we labeled the target variable that led to a specific broiler-rearing scenario depending on the age of the birds, the environmental dry-bulb temperature and relative humidity, the ammonia concentration, and the ventilation rate. The output (final rearing condition) was discretized into four categories ('Excellent', 'Good', 'Moderate', and 'Inappropriate'). In the third step, we used the dataset to develop tree models using the data-mining process. The random-tree model only presented accuracy for predicting the 'Excellent' and 'Moderate' rearing conditions. The decision-tree model had high accuracy and indicated that broiler age, relative humidity, and ammonia concentration play a critical role in proper rearing conditions. Using a large amount of data allows the data-mining approach to building up 'if-then' rules that indicate suitable environmental control decision-making by broiler farmers.

Smart Feeding Unit for Measuring the Pecking Force in Farmed Broilers.

Feeding is one of the most critical processes in the broiler production cycle. A feeder can collect data of force signals and continuously transform it into information about birds' feed intake and quickly permit more agile and more precise decision-making concerning the broiler farm's production process. A smart feeding unit (SFU) prototype was developed to evaluate the broiler pecking force and average feed intake per pecking (g/min). The prototype consisted of a power supply unit with a data acquisition module, management software connected to a computer for data storage, and a video camera to verify the pecking force during signal processing. In the present study, seven male Cobb-500 broilers were raised in an experimental chamber to test and commission the prototype. The prototype consisted of a feeding unit (feeder) with a data acquisition module (amplifier), with real-time integration for testing and intuitive operation with Catman Easy software connected to a computer to obtain and store data from signals. The sampling of average feed intake per pecking per broiler (g) was conducted during the first minute of feeding, subtracting the amount of feed provided per the amount of feed consumed, including the count of pecking in the first minute of feeding. An equation was used for estimating the average feed intake per pecking per broiler (g). The results showed that the average broiler pecking force was 1.39 N, with a minimum value of 0.04 N and a maximum value of 7.29 N. The average feed intake per pecking (FIP) was 0.13 g, with an average of 173 peckings per minute. The acquisition, processing, and classification of signals in the pecking force information were valuable during broilers' feeding. The smart feeding unit prototype for broilers was efficient in the continuous assessment of feed intake and can generate information for estimating broiler performance.

Estimating the urban environmental impact of gasoline-ethanol blended fuels in a passenger vehicle engine.

A large portion of urban emissions in developing countries come from old gasoline vehicles driven in metropolitan areas. The present study aimed to develop models to estimate the environmental impact of different contents of gasoline and ethanol mixtures (pure gasoline; 25, 50, 75% ethanol blended to gasoline; and 100% ethanol) in a flex-fuel engine. We tested the blended fuel using three different speeds and recorded the GHG emissions and engine output data. The data mining approach was used to develop environmental impact predictive models. The ethanol content in gasoline; the engine rotational speed 900, 2000, and 3000 rpm; and λ were used as attributes. The classification target was the environmental impact concerning the CO2 emission ("low," "average," and "high"). We employed the Random forest algorithm to develop predictive models. The mean values of CO2 concentrations for all studied fuel content were above 2.47% of the volume. The trees' models (accuracy 73%, κ =0.61) showed three alternatives for predicting the environmental impact based on the ethanol blend, the engine rotation, λ, and the air-fuel ratio. Such models might help policymakers develop educational campaigns to reduce short- and medium-term urban commuter traffic pollution in countries that lack suitable urban transportation.

Occupational risk factors in health of broiler-farm workers: A systematic review.

The present study aimed to identify gaps in literature regarding occupational risks to broiler farming workers. A systematic review was performed in which inclusion criteria were workers in poultry farms. The search was done between May and June 2019 with online papers. Keywords were "poultry farmer," "poultry worker," and "poultry workers" as terms of an axis of a theoretical framework. Results indicated as predominant topics lung diseases, nasal mucosa or paranasal sinus contamination, and aflatoxicosis. The identified gaps in scientific publications are related to mitigation of occupational risks. Prevalent described risks are associated to exposure to chemicals gases, vapors and aerosols, biological hazards (micro-organisms), ergonomic risks, wrong working posture, excessive body movement and inadequate behaviors. Preventive policies about poultry farmer's health and safety needs to be adopted to reduce potentially dangerous risk factors and increase productivity.

Young Broiler Feeding Kinematic Analysis as A Function of the Feed Type.

Past publications describe the various impact of feeding behavior of broilers on productivity and physiology. However, very few publications have considered the impact of biomechanics associated with the feeding process in birds. The present study aims at comparing the kinematic variables of young broiler chicks (3-4 days old; 19 specimens) while feeding them with three different feed types, such as fine mash (F1), coarse mash (F2), and crumbled feed (F3). The feeding behavior of the birds was recorded using a high-speed camera. Frames sequences of each mandibulation were selected manually and classified according to the temporal order that occurred (first, second, third, or fourth, and further). The head displacement and the maximum beak gape were automatically calculated by image analysis. The results did not indicate strong correlations between birds' weight, beak size (length and width), and the kinematic variables of feeding. The differences between the tested feed were found mostly in the first and second mandibulations, probably explained by the higher incidence of "catch-and-throw" movements in F3 (33%) and F1 (26%) than F2 (20%). The "catch-and-throw" movements in F1 (the smallest feed particle) mostly occurred in the first mandibulation, as in F3 (the largest feed particle) also occurred in the latest mandibulations. It might be suggested that the adoption of "catch-and-throw" in the latest mandibulations increases with larger particles. The kinematic variables in the latest mandibulations (from the third one on) seem to be similar for all feed types, which represent the swallowing phase. It might be inferred that the temporal sequence of the mandibulations should be essential to describe the kinematics of a feeding scene of broiler chickens, and the first and second mandibulations are potentially the key factors for the differences accounted by the diverse feed particle sizes.

Environmental impact of the on-road transportation distance and product volume from farm to a fresh food distribution center: a case study in Brazil.

The pollutants' emissions from on-road transport are critical pressure on the climate change scenario, and most developing countries rely on mostly diesel transportation. The current study aimed to estimate the environmental impact of the distance from the agricultural production area of fresh food (papaya, potato, and tomato) to a fresh food distribution center located in Campinas, Sao Paulo, Brazil. The way the products were carried was assessed for calculating the total transported volume. The total amount carried was measured, considering the number of trips multiplied by the total distance traveled within a year of supply. An online calculator was used to evaluate the amount of CO2 emission, and to allow the estimative of the amount of CO2-eq, that is the Global Warming Impact (GWP) in 100 years. The highest CO2 emission was identified in the potato transported from Paraná State to the distribution center, with a CO2-eq emission of 3237 t/year (64% of contribution), followed by the papaya from Bahia State (2723 t/year, 42% of contribution), and the tomato from Sao Paulo State (625 t/year, 71% of contribution). However, when computing the GWP, the highest value was found in the transport of potato from the Minas Gerais State (8 × 10-2 in 100 years) followed by the papaya from Rio Grande do Norte State (5 × 10-2 in 100 years) and the papaya from Bahia (3 × 10-2 in 100 years). The higher the amount of product transported by a trip, the smaller the environmental impact in the long run. A proper strategy to reduce the environmental impact would be to have large freight volume when transporting food from vast distances within continental countries.

Dietary yerba mate (Ilex paraguariensis) influences lipid profile of broiler meat / Erva mate na dieta influencia o perfil lipídico da carne de frangos de corte

Yerba mate ( Ilex paraguariensis) has in its composition organic compounds wich can modify chemical composition of broiler meat. This study aimed to evaluate the influence of yerba mate in chemical composition and lipid profile of broiler breast and thigh meat. The trial was conducted using 500 broiler chicks distributed in a completely randomized design with four treatments (0.1; 0.2; 0.4, and 0.6%) and five replicates with 25 chicks each. The chicken were raised form 1 to 42 days old and slaughtered for analysis of breast and thigh meat. The addition of mate did not affect the chemical composition and the lipid profile of the chicken breast, however, the composition of the meat of thigh meat was affected. It was observed effect of the addition of the yerba mate to saturated, unsaturated, monounsaturated and polyunsaturated fatty acids in the chicken meat. Stands out the reduction in saturated fatty acid concentrations and the increase in the concentrations of polyunsaturated fatty acids, especially Linolenic and Eicosapentaenoic, thus demonstrating the potential of mate grass in altering the lipid profile of poultry meat.(AU)

A erva mate ( Ilex paraguariensis) possui em compostos orgânicos com propriedades de modificar a composição química de carne de frangos de corte, desta maneira este estudo avaliou a influência da erva mate sobre a composição química e o perfil lipídico de carne de peito, coxas e sobrecoxas de frangos de corte. Foram utilizados 500 pintainhos de corte distribuídos em um delineamento inteiramente casualizado com inclusões de erva mate nas dietas (0.1; 0.2; 0.4, e 0.6%) com quatro repetições de 25 aves em cada tratamento, criados de 1 a 42 dias de idade para posterior abate e análises da composição de cortes cárneos. A adição de erva mate não afetou a composição química e o perfil lipídico dos peitos de frangos, porém a composição da carne de sobrecoxas foi afetada. Foi observado efeito da adição da erva mate em ácidos graxos saturados, insaturados, monoinsaturados e poli-insaturados na carne de sobrecoxas de frango, destacando-se a redução nas concentrações de ácidos graxos saturados e o aumento das concentrações dos ácidos poli-insaturados, em especial Linolênicoe Eicosapentaenoico, demonstrando assim o potencial da erva mate em alterar o perfil lipídico da carne de aves.(AU)

Dietary yerba mate (Ilex paraguariensis) influences lipid profile of broiler meat / Erva mate na dieta influencia o perfil lipídico da carne de frangos de corte

Yerba mate ( Ilex paraguariensis) has in its composition organic compounds wich can modify chemical composition of broiler meat. This study aimed to evaluate the influence of yerba mate in chemical composition and lipid profile of broiler breast and thigh meat. The trial was conducted using 500 broiler chicks distributed in a completely randomized design with four treatments (0.1; 0.2; 0.4, and 0.6%) and five replicates with 25 chicks each. The chicken were raised form 1 to 42 days old and slaughtered for analysis of breast and thigh meat. The addition of mate did not affect the chemical composition and the lipid profile of the chicken breast, however, the composition of the meat of thigh meat was affected. It was observed effect of the addition of the yerba mate to saturated, unsaturated, monounsaturated and polyunsaturated fatty acids in the chicken meat. Stands out the reduction in saturated fatty acid concentrations and the increase in the concentrations of polyunsaturated fatty acids, especially Linolenic and Eicosapentaenoic, thus demonstrating the potential of mate grass in altering the lipid profile of poultry meat.

A erva mate ( Ilex paraguariensis) possui em compostos orgânicos com propriedades de modificar a composição química de carne de frangos de corte, desta maneira este estudo avaliou a influência da erva mate sobre a composição química e o perfil lipídico de carne de peito, coxas e sobrecoxas de frangos de corte. Foram utilizados 500 pintainhos de corte distribuídos em um delineamento inteiramente casualizado com inclusões de erva mate nas dietas (0.1; 0.2; 0.4, e 0.6%) com quatro repetições de 25 aves em cada tratamento, criados de 1 a 42 dias de idade para posterior abate e análises da composição de cortes cárneos. A adição de erva mate não afetou a composição química e o perfil lipídico dos peitos de frangos, porém a composição da carne de sobrecoxas foi afetada. Foi observado efeito da adição da erva mate em ácidos graxos saturados, insaturados, monoinsaturados e poli-insaturados na carne de sobrecoxas de frango, destacando-se a redução nas concentrações de ácidos graxos saturados e o aumento das concentrações dos ácidos poli-insaturados, em especial Linolênicoe Eicosapentaenoico, demonstrando assim o potencial da erva mate em alterar o perfil lipídico da carne de aves.

Practical assessment of spaghetti breast in diverse genetic strain broilers reared under different environments

Brazilian processing plants have identified the so-calledspaghetti breast myopathy characterized by muscular dystrophy of unknown etiology. This study aimed at estimating the incidence of spaghetti breast myopathyin broilers from three commercial genetic strains (Ross, Cobb, Hubbard) reared in two different housing systems (DH, Dark house, and TS, Tunnel system), presenting different controlled ventilation systems and light availability. Breast meat samples (n=5,580) were collected and macroscopically evaluated for spaghetti breast myopathy according to a 0-2 scale, as 0 = normal, 1 = intermediate or moderate, and 2 = severe. A higher number of broilers reared in DH presented normal breasts and moderate myopathy relative to TS-reared birds. Ross broilers presented a higher incidence of normal breasts compared with Cobb and Hubbard broilers. The risk of presenting spaghetti breast myopathy was higher in broilers reared in DH than those in reared in TS, indicating that the exposure to DH environmental conditions may increase the chance of myopathy incidence. Broilers reared in dark houses presented 26% higher chance and 13% higher risk of showing spaghetti-breast myopathy the than those reared in tunnel-ventilated systems.(AU)

Analysis of barriers to Brazilian chicken meat imports

Trade liberalization during the last decades has increased among nations as a result of decreased tariffs. However, during the same period, market agents have created new protection measures to replace such mechanisms in an attempt to promote the domestic economic stability of countries, while expanding and ensuring the trade between nations. Considering that Brazil is the second largest broiler producer and chicken-meat exporter worldwide, the present study proposed to analyze the main barriers imposed on Brazilian chicken meat imports by the ten major importing countries. This is a documentary research with primary and secondary data, of a descriptive-exploratory nature, under a qualitative approach. Semi-structured questionnaires including open- and close-ended questions were sent using Survey Monkey software to the Brazilian Association of Animal Protein. The study revealed that technical requirements are those most often imposed by the importing countries, indicating their concern about the safety, quality, and origin of the imported good. Commercial requirements do not constitute a problem for the growth of Brazilian chicken meat exports; however, the requirements made by some countries preclude the exports.(AU)

Broiler carcass condemnation pattern during processing

This study aimed to identify the influence of climate pattern and rearing conditions on broiler carcass condemnations observed during processing. We evaluated the registered data of 2015 from the federal inspection files in all broiler slaughterhouses located in the state of Mato Grosso do Sul, Midwestern Brazil. The percentages of condemnations by airsacculitis, cellulitis, dermatosis, ascites syndrome, total carcass condemnations, and average broiler weight at 42 days were analyzed. Data were associated with housing systems and season of the year in which each flock was reared. Two-way ANOVA was applied to the data in a completely randomized design 4×3 (four seasons and three houses) and compared by Tukey's test. The results indicated that the housing system did not affect the studied condemnations, and seasons of the year did not change condemnation by airsacculitis; however, the other pathologies leading to carcass condemnations were affected by season. Condemnations by cellulite were higher during summer than in winter. For dermatosis, the maximum index appears during summer and the lowest during winter and spring. The ascites syndrome presented the smallest index in summer and winter, and the minimum value was found in spring. The average bird weight was higher in autumn than in winter and spring. Type of broiler rearing did not affect the carcass condemnation index. Summer was the most detrimental period regarding the condemnation rates for the pathologies studied, mainly cellulitis and dermatosis, while the highest average weight of birds was found during autumn and spring.(AU)

Origin of broiler carcass condemnations

The objective of the present research was to study the incidence of broiler carcass condemnations over eleven years and identify the productive phase that causes greater loss in slaughter process. The origin of these condemnations was determined before and after fasting. Evaluated broilers were reared in positive pressure warehouses and slaughtered between 28 and 34 days old with carcass weight ranging from 0.7 to 1.4 kg. Fasting occurred, on average, 9 h before the slaughter. Condemnation and slaughter data were collected from 2004 to 2014 in a slaughterhouse with slaughter capacity of 120,000 broilers/day. The causes of rearing condemnations were airsaccullitis, arthritis, abscess, ascites, cachexia, cellulitis, colibacillosis, dermatosis, salpingitis, hemorrhagic syndrome, and neoplasia; and the causes of pre-slaughter and slaughter condemnations were bruising, fracture, inadequate bleeding, excessive scaling, contamination, dehydration, death at the platform, disgusting appearance, and delayed evisceration. The mean values of total and partial condemnations per year, occurrence and proportion of condemnations index (OCI) for every thousand broilers slaughtered, and rates of pre and post-fasting condemnations were calculated. Condemnations rates (%) and OCI were higher after fasting; partial and total contamination stood out, with a frequency of 77% and 30%, respectively, after fasting. Long fasting, uneven lots or unbalanced equipment may cause extravasation of the gastrointestinal contents and contaminate broiler carcasses. Practices such as monitoring fasting and equipment adjustment to broiler carcass size may reduce carcass condemnation incidence.(AU)

Practical assessment of spaghetti breast in diverse genetic strain broilers reared under different environments

Brazilian processing plants have identified the so-calledspaghetti breast myopathy characterized by muscular dystrophy of unknown etiology. This study aimed at estimating the incidence of spaghetti breast myopathyin broilers from three commercial genetic strains (Ross, Cobb, Hubbard) reared in two different housing systems (DH, Dark house, and TS, Tunnel system), presenting different controlled ventilation systems and light availability. Breast meat samples (n=5,580) were collected and macroscopically evaluated for spaghetti breast myopathy according to a 0-2 scale, as 0 = normal, 1 = intermediate or moderate, and 2 = severe. A higher number of broilers reared in DH presented normal breasts and moderate myopathy relative to TS-reared birds. Ross broilers presented a higher incidence of normal breasts compared with Cobb and Hubbard broilers. The risk of presenting spaghetti breast myopathy was higher in broilers reared in DH than those in reared in TS, indicating that the exposure to DH environmental conditions may increase the chance of myopathy incidence. Broilers reared in dark houses presented 26% higher chance and 13% higher risk of showing spaghetti-breast myopathy the than those reared in tunnel-ventilated systems.