Comparison of microbial load in immersion chilling water and poultry carcasses after 8, 16 and 24 working hours

As atividades dos estabelecimentos de abate de frangos são conhecidas por utilizarem grandes volumes de água durante seus processos, principalmente no processo de resfriamento das carcaças de frangos. Parte desse volume utilizado se faz necessário, em cumprimento à legislação que determina que cada tanque do sistema de pré-resfriadores contínuos por imersão deve ser completamente esvaziado, limpo e desinfetado no final de cada período de trabalho (oito horas). O objetivo deste estudo foi comparar a carga microbiana das águas do sistema de resfriamento e das carcaças de frango ao final de oito, dezesseis e vinte e quatro horas de trabalho do abatedouro, para possível redução do número de vezes do completo esvaziamento dos tanques do sistema de resfriamento. Foram avaliadas, por meio de métodos convencionais microbiológicos e físico-químicos, amostras da água de abastecimento (n=69), visando a evitar possível interferência nas contagens das águas do sistema de resfriamento, amostras de carcaças de frango antes (n=345) e após (n=345) sua passagem pelo sistema de resfriamento e amostras de águas do último estágio do sistema de resfriamento de carcaças (n=69). Os resultados obtidos demonstraram que não houve diferença significativa na carga microbiana das amostras entre as três jornadas de trabalho do estabelecimento, sugerindo que a redução é segura, diminuindo assim o volume de águas residuais e seu impacto no meio ambiente, bem como melhorando o uso racional do tempo de processamento.

Evaluation of the owner's perception in the use of homemade diets for the nutritional management of dogs

Many dog owners see homemade diets as a way of increasing the bond with their pets, even though they may not have the convenience of commercial diets. Modifications of ingredients, quality and proportion might change the nutritional composition of the diet, generating nutritional imbalances. The present study evaluated how dog owners use and adhere to homemade diets prescribed by veterinary nutritionists over an extended period of time. Forty-six owners of dogs fed a homemade diet for at least 6 months were selected for the present study. Owners were invited to answer questions by first reading all possible answers and then selecting the one that best indicated their opinion. The results were evaluated through descriptive statistics. Thirty-five owners (76·1 %) found that the diets are easy to prepare. Fourteen owners (30·4 %) admitted to modifying the diets, 40 % did not adequately control the amount of provided ingredients, 73·9 % did not use the recommended amounts of soyabean oil and salt, and 34·8 % did not correctly use the vitamin, mineral or amino acid supplements. Twenty-six owners (56·5 %) reported that their dogs refused to eat at least one food item. All of these alterations make the nutritional composition of the diets unpredictable and likely nutritionally imbalanced. Although homemade diets could be a useful tool for the nutritional management of dogs with certain diseases, not all owners are able to appropriately use this type of diet and adhere to it for an extended period of time and this limitation needs to be considered when recommending the use of homemade diets.

Comparison of the digestive efficiency of extruded diets fed to ferrets (Mustela putorius furo), dogs (Canis familiaris) and cats (Felis catus)

The digestive tract of ferrets is anatomically simple, with no caecum, ileocolic valve or external differentiation between the transition of ileum and colon. The species has a short large intestine that provides minor contributions to the digestive process. Aiming to better understand the digestibility efficiency of ferrets, the present study compared the digestibility of extruded diets with different amounts of macronutrients fed to dogs, cats and ferrets. Three formulations for cat maintenance were used (values in % of DM basis): high carbohydrate (HC; nitrogen-free extract (NFE) = 54 %, protein = 31 % and fat = 8 %); moderate carbohydrate (MC; NFE = 37 %, protein = 41 % and fat = 10 %); and low carbohydrate (LC; NFE = 19 %, protein = 46 % and fat = 23 %). Apparent total tract macronutrient digestibility was determined by the method of total collection of faeces. Results were compared by ANOVA, considering the diet and species effects and their interactions. Means were compared by the Tukey's test (P < 0·05). Dogs and cats presented similar food intakes, but ferrets consumed almost two times more food (g/kg body weight). Species × diet interactions were verified for apparent total tract digestibility (ATTD; P < 0·05). Ferrets presented lower DM digestibility than dogs and cats for all three diets (P < 0·05), lower NFE digestibility than dogs for the three diets and lower NFE digestibility than cats for the HC and LC diets (P < 0·05). For crude protein (CP), ferrets presented lower ATTD than dogs and cats (P < 0·05), whereas for fat, dogs and ferrets presented similar ATTD, and higher values than those presented by cats (P < 0·05). Kibble diets had a lower DM, CP and NFE digestibility when fed to ferrets compared with dogs and cats. Fat digestibility was similar between dogs and ferrets and higher than that for cats.

Prediction of crude protein digestibility of animal by-product meals for dogs by the protein solubility in pepsin method

Animal by-product meals have large variability in crude protein (CP) content and digestibility. In vivo digestibility procedures are precise but laborious, and in vitro methods could be an alternative to evaluate and classify these ingredients. The present study reports prediction equations to estimate the CP digestibility of meat and bone meal (MBM) and poultry by-product meal (PM) using the protein solubility in pepsin method (PSP). Total tract CP digestibility of eight MBM and eight PM samples was determined in dogs by the substitution method. A basal diet was formulated for dog maintenance, and sixteen diets were produced by mixing 70 % of the basal diet and 30 % of each tested meal. Six dogs per diet were used to determine ingredient digestibility. In addition, PSP of the MBM and PM samples was determined using three pepsin concentrations: 0·02, 0·002 and 0·0002 %. The CP content of MBM and PM ranged from 39 to 46 % and 57 to 69 %, respectively, and their mean CP digestibility by dogs was 76 (2·4) and 85 (2·6) %, respectively. The pepsin concentration with higher Pearson correlation coefficients with the in vivo results were 0·0002 % for MBM (r 0·380; P = 0·008) and 0·02 % for PM (r 0·482; P = 0·005). The relationship between the in vivo and in vitro results was better explained by the following equations: CP digestibility of MBM = 61·7 + 0·2644 × PSP at 0·0002 % (P = 0·008; R (2) 0·126); and CP digestibility of PM = 54·1 + 0·3833 × PSP at 0·02 % (P = 0·005; R (2) 0·216). Although significant, the coefficients of determination were low, indicating that the models were weak and need to be used with caution.

Effects of β-(1→3,1→6)-d-glucan and density of diets on the blood profiles of immunologically challenged weaned piglets

An experiment was conducted to evaluate the effects of two levels of the β-(1→3,1→6)-d-glucan (0 and 500ppm) from yeast Saccharomyces cerevisiae and two levels of energy (3300 and 3450kcalMEkg(-1)) on the hematological, immunological and, biochemical profiles of thirty-six 21-days-old weaned piglets, challenged with 150μgkg(-1) of BW lipopolysaccharide (LPS) from Escherichia coli serotype 055:B5. The experimental design was a randomized complete block design in a 2×2 factorial arrangement with nine replicates per treatment and, one animal per experimental unit. The data were analyzed in accordance with the multivariate analysis procedure of SAS and, the treatment means of parametric and non-parametric data were compared by Bonferroni's test (P<0.05) and, by Dunn's test (P<0.05), respectively. The data of the blood profiles of alanine aminotransferase, alkaline phosphatase and, creatinine showed that LPS did not cause kidney or liver damage in the animals. The addition of beta-glucan in the diets did not prove the robustness of its effect and biological relevance when provided with low nutrient-density. However, its addition combined with the high-nutrient-density diets showed less marked hypoglobulinemia in piglets, which may have contributed to the decreasing of the synthesis of inflammatory mediators.

Carcass characteristics and meat quality of lambs fed high concentrations of crude glycerin in low-starch diets

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Clonal relatedness and resistance patterns of Salmonella Corvallis from poultry carcasses in a Brazilian slaughterhouse

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Produção, caracterização nutricional e utilização de farinhas e óleos de resíduos de peixes neotropicais em dietas para Tilápia do Nilo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The strategic application of elecytolyte balance to minimize heat stress in broilers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Strategic use of dietary electrolyte balance and ratio for broiler chickens

The literature reports dealing with the dietary electrolyte ratio (K+Cl)/ Na are rare, although the concept has been proposed by Mongin in 1981. Thus, its application appears to be limited as a nutritional strategy in feed formulation, which usually meets only the minimum nutritional recommendations in Na, K and Cl. The objective of this study was to evaluate the performance of broilers submitted to different dietary electrolyte balances (DEB) Na+K-Cl and dietary electrolyte ratio (DER) from 1 to 21 d of age. A total of 1575 male 1-d old broiler chicks were randomly assigned to 5 treatments with 9 replicates of 35 chicks each. The treatments consisted of diets with 5 relation of electrolytes, arising from combinations DEB/DER 150/3, 250/2, 250/3, 250/4 and 350/3, with use of NaCl, NaHCO3, KCl, K2SO4 and CaCl2. All diets were corn-soybean meal based and formulated to meet or exceed the NRC (1994) requirements. Chicks had ad libitum access to feed and water in floor pens with wood shavings as litter. Body weight, feed intake and feed conversion ratio were measured at 21 d of age. It was found that only the feed conversion was significantly affected (P = 0.0142) by the combinations of relation of electrolytes (DEB and DER). The supplementation levels in DEB and DER were made to fit the data into a surface analysis to allow increasing levels of DEB (150–350 mEq/kg) and narrow and broad ratio of DER (2–4). For the canonical analysis of response surface was obtained the stationary point for body weight (DEB = 255.77 mEq/kg, and DER = 2.73:1) the value was 942.02 g; for feed intake (DEB = 251.69 mEq / kg and DER = 3.51:1), the value was 1200.02 g; and for feed conversion (DEB = 254.62 mEq/kg and DER = 3.06:1) the value was 1.35. The results of this experiment indicated that the best performance was obtained with combinations of relation of electrolytes for DEB between 251 and 255 mEq/kg and DER between 2.73:1 and 3.5:1.

Strategic feed formulation for relation of electrolytes to promote performance and prevent heat stress in broilers

An experiment was conducted to evaluate the impact in relation of dietary electrolytes, based on changes in the balance Na+K-Cl (DEB) and the ratio (K+Cl)/Na (DER) on the performance and survival of broilers subjected to acute heat stress. A total of 1575 male broiler chicks from 1 to 46 d of age were allocated in a 5x3 factorial arrangement in a completely randomized design, totaling of 15 treatments with 3 replicates of 35 birds each. The treatments consisted of 5 diets with electrolyte balances, arising from combinations DEB/DER (150/3, 250/2, 250/3, 250/4 and 350/3), associated with different times of application or not of the acute heat stress on birds at 25 and 36 d old. All diets were cornsoybean meal based and formulated to meet or exceed NRC requirements. Chicks had ad libitum access to feed and water in floor pens with wood shavings as litter. It was possible to verify that a DEB of 250 mEq/kg and a DER very close to the 3:1 providing a more nutritionally adequate diet. There was, however, the impossibility of obtaining a more suitable electrolyte ratio for a very low DEB (150 mEq/kg) or very high (350 mEq/kg) and also, to a very narrow DER (2:1) or very wide (4:1), due to an unfavorable performance and survival rate of birds in these conditions electrolytes adjustments of K, Na and Cl. There was clear indication, with significant difference (P < 0.05), that the DER has the potential to improve the performance of broilers, since simultaneous adjustment made in DEB, even in conditions of acute stress. The results of performance and survival rate of this study also indicate clearly that DER could not replace the DEB, and vice versa, in practical diets for broilers. Therefore, it can be affirmed that the strategic formulation of the correct electrolyte balance for DEB and DER enhances the performance and is able to prevent the effect of heat stress in broiler chickens, leading to better performance and survival.

The use of nonlinear programming as a tool for maximum profit feed formulation of broilers

The purpose of this study was to compare linear and nonlinear programming models for feed formulation, for maximum profit, considering the real variation in the prices of the corn, soybean meal and broilers during the period from January of 2008 to October of 2009, in the São Paulo State, Brazil. For the nonlinear formulation model, it was considered the following scenarios of prices: a) the minimum broiler price and the maximum prices of the corn and soybean meal during the period, b) the mean prices of the broiler, corn and soybean meal in the period and c) the maximum broiler price and the minimum prices of the corn and soybean meal, in the considered period; while for the linear formulation model, it was considered just the prices of the corn and the soybean. It was used the Practical Program for Feed Formulation 2.0 for the diets establishment. A total of 300 Cobb male chicks were randomly assigned to the 4 dietary treatments with 5 replicate pens of 15 chicks each. The birds were fed with a starter diet until 21 d and a grower diet from 22 to 42 d of age, and they had ad libitum access to feed and water, on floor with wood shavings as litter. The broilers were raised in an environmentally-controlled house. Body weight, body weight gain, feed intake, feed conversion ratio and profitability (related to the prices variation of the broilers and ingredients) were obtained at 42 d of age. It was found that the broilers fed with the diet formulated with the linear model presented the lowest feed intake and feed conversion ratio as compared with the broilers fed with diets from nonlinear formulation models. There were no significant differences in body weight and body weight gain among the treatments. Nevertheless, the profitabilities of the diets from the nonlinear model were significantly higher than that one from the linear formulation model, when the corn and soybean meal prices were near or below their average values for the studied period, for any broiler chicken price.

Bacterial oxycarotenoids added into broiler chickens ration modify breast meat color

Some markets around the world demand for well pigmented poultry products, what justifies the intentional use of synthetic additives in rations during breeding. The inconvenient for that practice most times is the elevated price of these products, beyond the argument of being chemicals, which may not be viable for some production systems. So, the aim of this experiment was to check on the ability of natural red oxycarotenoids produced by R. gelatinosus to modify broilers breast meat color. Bacterial biomass containing oxycarotenoids were added into Cobb broilers finisher diets at 0, 1.0, 2.0 and 3.0 g/kg and fed during 10 days (35-45 d). Five replicates (10 birds each) were performed. At days 35, 37, 39, 41, 43 and 45, 100 birds were slaughtered scalded, defeathered and eviscerated. Data on live and carcass weights were recorded. After cooling, color parameters of meat were determined on breast surface using a HunterLab XE Plus colorimeter calibrated with black and white standard tiles. Regression analysis was used for the investigation of relationships between days of consumption and biomass concentration on color values, live weight and carcass yield. Results showed that redness of breast meat was significantly influenced by the biomass concentration in a linear effect (P=0.0056) and also by the time of consumption, in a quadratic effect (P=0.0232). Days of consumption also affected yellowness and lightness with significant quadratic responses (P=0.0225 and P<0.0001, respectively). Birds live weight increased significantly during the application of the experimental diets (P<0.0001), showing no negative influence of the biomass administration. Also no deleterious effects derived from the application of the product were observed on carcass yield. So we concluded that R. gelatinosus oxycarotenoids present in the bacterial biomass can modify broilers breast meat color, performing as an alternative pigmenting additive in poultry production.

Accurate adjustment of feed formulation for broiler chickens on performance and lipid composition of meat

Most consumers consider the fat of chicken meat undesirable for a healthy diet, due to the high levels of saturated fatty acids and cholesterol. The purpose of this experiment was to investigate the influence of changes in dietary metabolizable energy level, associated with a proportional nutrient density variation, on broiler chickens performance and on the lipid composition of meat. Males and females Cobb 500 broilers were evaluated separately. Performance evaluation followed a completely randomized design with factorial 6x3 arrangement - six energy levels (2,800, 2,900, 3,000, 3,100, 3,200 and 3,300 kcal/kg) and three slaughter ages (42, 49 and 56 days). Response surface methodology was used to establish a mathematical model to explain live weight, feed intake and feed conversion behavior. Total lipids and cholesterol were determined in skinned breast meat and in thigh meat, with and without skin. For lipid composition analysis, a 3x3x2 factorial arrangement in a completely randomized design - three ration’s metabolizable energy levels (2,800, 3,000 and 3,300 kcal/kg), three slaughter ages (42, 49 and 56 days) and two sexes - was used. The reduction in the diet metabolizable energy up to close to 3,000 kcal/kg did not affect live weight but, below this value, the live weight decreased. Feed intake was lower when the dietary energy level was higher. Feed conversion was favored in a direct proportion to the increase of the energy level of the diet. The performance of all birds was within the range considered appropriate for the lineage. Breast meat had less total lipids and cholesterol than thigh meat. Thigh with skin had more than the double of total lipids of skinned thigh, but the cholesterol content did not differ with the removal of the skin, suggesting that cholesterol content is not associated with the subcutaneous fat. Intramuscular fat content was lower in the meat from birds fed diets with lower energy level. These results may help to define the most appropriate nutritional management. Despite the decrease in bird’s productive performance, the restriction of energy in broiler chickens feed may be a viable alternative, if the consumers are willing to pay more for meat with less fat.

Digestibilidade e exigência de aminoácidos para rã-touro

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)