ABSTRACT The objective of this study was to evaluate whether the addition of the enzymes phytase and xylanase, isolated or associated, in the liquid form after feed pelletization could improve energy utilization and digestibility of calcium and phosphorus by broiler chickens. Three experiments were performed using 120 birds each, divided into five treatments with eight replicates per group (n = 3), identified as: experiment 1 (xylanase: control, 1000 IU, 1500 IU, 2000 IU, 2500 IU), experiment 2 (phytase: control, 500 FTU, 1000 FTU, 1500 FTU, 2000 FTU), experiment 3 (xylanase + phytase: control, 3000 IU + 500 FTU, 3000 IU + 1000 FTU, 3000 IU + 1500 FTU, 3000 IU + 2000 FTU). Samples for digestibility tests were collected at 14 to 21 days of age. Therefore, the inclusion of liquid phytase and liquid phytase + xylanase after pelletization in broiler diets has become a relevant way to reduce the inclusion of inorganic P, which can reduce the cost of feed and P excretion in the environment. Furthermore, it is an interesting strategy to avoid enzyme denaturation in the pelleting process.

Abstract The objective of this study was to evaluate physically and chemically chicken breasts with different degrees of white striping (WS), as well as its effect on the process and quality of nuggets and hamburgers. Chicken breasts fillets were obtained from male chicken broilers weighing approximately 3 kg at the slaughterhouse and classified based on the WS degree as normal, moderate or severe. Chemical composition was evaluated (moisture, crude protein, fat, mineral matter and total collagen), as well as pH, color (CIELab), thiobarbituric acid reactive substances, water holding capacity, cooking loss, shear force, dough stability, cooking yield and size reduction of nuggets and hamburgers. The presence of severe WS in chicken breasts changed its chemical composition leading to increased content of fat and collagen, higher lipid oxidation (TBARS), as well as lower crude protein. In addition, breasts with severe WS showed greater cooking loss and lower water holding capacity, besides increased yellow intensity. The presence of WS did not affect significantly the production and quality of chicken nuggets and hamburgers, causing only few changes in hamburger´s cooking loss, and therefore, it is a good destination for this kind of meat.

Abstract The objective of this work was to develop innovative formulations of dulce de leche made with sheep's milk with and without the addition of sheep’s milk cream and evaluate the shelf life of these products. Physicochemical and microbiological evaluations were performed on sheep’s pasteurized milk and cream, as well as on dulce de leche right after production and during the storage time. Addition of cream to sheep dulce de leche did not change the physicochemical and microbiological parameters between formulations. The dulce de leche showed dark color and adequate results of protein, fat, total and microbiological counts (thermotolerant coliforms, Staphylococcus aureus, Salmonella sp. in all evaluations, and total mesophilic aerobic up to 150 days of storage). Innovative formulations of dulce de leche made by sheep’s milk were developed, differentiated from those existing in the Brazilian market, but a specific legislation is required in Brazil focused on the specific characteristics and quality parameters of sheep’s milk and its derivatives.

Abstract This study aimed to isolate lactic acid bacteria from sheep milk products and to characterize these microorganisms with a focus on their antimicrobial, proteolytic and lipolytic activities. Raw milk, pasteurized milk, pasteurized cream, and butter samples were collected, lactic acid bacteria were isolated and their proteolytic, lipolytic and antimicrobial activities were evaluated. Lactic acid bacteria counts were higher in raw milk collected at the farm number 4 (8.91 ± 0.05 log CFU/mL), in which adequate hygienic practices were observed for pre- and post-milking. A total of 253 isolates were obtained, and among them 37 were lactic acid bacteria, where 19 showed some type of activity, most of which from raw milk. Among the isolates of lactic acid bacteria, 48.65% (n=18) showed proteolytic activity, 13.51% (n=5) lipolytic activity, 10.81% (n=4) showed both proteolytic and lipolytic activities, and only 2.70% (n=1) showed antimicrobial activity. Isolation of lactic acid bacteria with technological properties demonstrated their potential use as starter cultures in processing of fermented dairy products.

ABSTRACT The objective of this study was to evaluate performance, hematological parameters, leukocyte counts, and respiratory microbiota of broilers under heat stress receiving eucalyptus oil supplementation. Cobb broilers (n = 1200) were randomly distributed on the first day of life in a factorial arrangement with additional treatment (2 × 2 + 1) with two periods of oil administration via drinking water (daily, from 18 to 35 days of life) and two periods of oil administration via spray (daily, from 18 to 35 days of age) plus a control treatment, consisting of twelve replications, with 20 animals each. The birds were kept in a controlled environment with constant temperature at 32 °C to induce heat stress by infrared heaters. Eucalyptus oil was supplied by drinking water (1 L of oil to 4000 L of water) or by spray applications with a pump (1 L of oil to 200 L of water). Bird weight was recorded at 42 days of age, along with remaining feed, to determine weight gain, feed intake, and feed conversion. In addition, one blood sample from each bird repetition was collected for hematological and leucocytic evaluation. To assess respiratory microbiota, a tracheal flushing was performed for bacteria counts. There was no difference in performance, hematological parameters, and leukocyte counts, except hematocrit, which was lower in birds that received eucalyptus oil after 18 days of age. No significant differences were observed in the respiratory microbiota comparing oil-treated and -untreated groups. Although it was not possible to verify statistical difference, the birds that received eucalyptus oil via spray plus spray from 18 days old showed lower bacterial counts and absence of isolation of Gram negatives, while the control group was the one with the highest number of Gram negatives. Therefore, eucalyptus oil can be used for heat-stressed broilers without impairing their development.

RESUMEN Objetivo. El objetivo evaluar la ocurrencia de protozoos gastrointestinales en terneros lecheros y de identificar posibles factores de riesgo para infección. Materiales y métodos. Se recogieron 243 muestras de heces de terneros de hasta 60 días de edad en 43 granjas lecheras ubicadas en la región del oeste del estado de Santa Catarina, Brasil. Las muestras fueron examinadas por la técnica de centrifugación-flotación. Resultados. Como resultado, Giardia estaba presente en 26.75% (65/243) de todas las muestras, Eimeria en 21.81% (53/243), y Cryptosporidium en 20.99% (51/243). Además, 46.50% (113/243) de las muestras fueron negativas para cualquier protozoos, mientras que 39.10% (95/243) y 14.40% (35/208) mostraron infecciones simples y mixtas, respectivamente. Hubo una mayor asociación entre Cryptosporidium y Giardia (6.99%) en los casos de infecciones mixtas. Sin embargo, la asociación de triple protozoos tenía la menor prevalencia de infecciones mixtas (2.06%). Epidemiológicamente, se aplicó un cuestionario para determinar los factores de riesgo para estas infecciones parasitarias. Se han identificado algunos factores de riesgo de infecciones por Cryptosporidium, destacando manejo de la alimentación, periodo de tiempo que los terneros permanecieron con sus madres (vacas), y el contacto con los perros; el riesgo de contraer Giardia incrementado en función de la fuente de la leche, mientras que el tipo de suelo de las camas, y la edad fueron nombrados como los riesgos de factores de Eimeria. Conclusiones. Es posible confirmar que Giardia, Cryptosporidium y Eimeria pueden infectar a terneros lecheros, y el conocimiento de algunos factores de riesgo asociados a la infección en terneros.

ABSTRACT Objective. This study aimed to evaluate the occurrence of gastrointestinal protozoa in dairy calves and to identify potential risk factors for this type of infection. Materials and methods. For this purpose, 243 fecal samples were collected from calves up to 60 days of age in 43 dairy farms located in the West region of Santa Catarina state, Brazil. Samples were examined by centrifugal-flotation technique. Results. As a result, Giardia was present in 26.75% (65/243) of all samples, Eimeria in 21.81% (53/243), and Cryptosporidium in 20.99% (51/243). Additionally, 46.50% (113/243) of the samples were negative for any protozoa, while 39.10% (95/243) and 14.40% (35/208) showed single and mixed infections, respectively. There was a higher association between Cryptosporidium and Giardia (6.99%) in cases of mixed infections. However, the triple protozoa association had the lowest prevalence in mixed infections (2.06%). Epidemiologically, a questionnaire was applied to determine risk factors for these parasitic infections. Based on the statistical model applied, some risk factors for Cryptosporidium infections were identified, highlighting feeding management, period of time that calves stayed with their mothers (cows), and contact with dogs; the risk of contracting Giardia increased according to the milk source, while the floor type bedding, and age were appointed as risks factors for Eimeria. Conclusions. Therefore, it is possible to confirm that Giardia, Cryptosporidium and Eimeria may infect dairy calves, and the knowledge of some risk factors associated to their infection in calves.

Analisaram-se características qualitativas da carne do peito de frangos de corte alimentados com rações suplementadas com diferentes concentrações (0; 0,3 e 0,5mg kg-1) de selênio nas formas de selenometionina e selenito de sódio. Foram utilizados 1050 pintainhos machos de um dia de idade da linhagem Cobb, que foram distribuídos em delineamento inteiramente casualizado em esquema fatorial em 5 tratamentos (duas concentrações x duas fontes + tratamento controle, sem adição de selênio) e sete repetições de trinta aves cada e receberam rações isoproteicas e isoenergéticas em todas as fases de criação (1 a 21, 22 a 35 e 36 a 42 dias). Aos 42 dias de idade, TBARS (substâncias reativas ao ácido tiobarbitúrico) após armazenamento a 4ºC por um, sete e 15 dias e 30 dias sob congelamento (15ºC), coloração (CIELab), capacidade de retenção de água, perdas de peso por cocção, força de cisalhamento, pH e concentração de selênio foram determinadas na carne do peito das aves abatidas. Os resultados indicaram que o uso da selenometionina ocasiona queda da oxidação da carne e luminosidade aos 15 dias de armazenamento a 4ºC. Existiu um efeito positivo da suplementação da ração com as diferentes fontes e concentrações de selênio sobre a qualidade da carne do peito das aves. Houve efeito linear dos níveis dietéticos de selênio na quantidade de selênio depositado no músculo, e a fonte orgânica (selenometionina) foi mais efetiva que a inorgânica (selenito de sódio) na conservação da carne de frango.

Qualitative characteristics of breast meat of broilers fed diets supplemented with different concentrations (0; 0.3 and 0.5mg kg-1) of selenium in the form of selenomethionine and sodium selenite were analyzed. A total of 1050 one-day-old male Cobb broiler chicks were arranged factorially at random to five treatments (two concentrations x two sources + control diet without addition of selenium) with 7 replications of thirty birds each and received an isonitrogenous and isocaloric diets in all phases according to their ages (1-21, 22-35, and 36-42 days). At 42 days of age, TBARS (thiobarbituric acid reactive substances) after storage at 4ºC for one, seven and 15 days and also after 30 days under freezing temperatures (-15°C), color (CIELab), water holding capacity, cooking loss, shear force, pH and selenium concentration were determined in slaughtered birds breast meat. Results indicated that the use of selenomethionine provides less lightness and lower oxidation in chicken breast meat stored up to 15 days at 4°C. There was a positive effect of dietary different sources and levels of selenium on breast meat quality of broilers. It was observed a linear effect of dietary selenium levels on the amount of selenium deposited in the muscle, and the organic source (selenomethionine) is more effective than inorganic one (sodium selenite) for broiler meat conservation.

Este estudo teve como objetivo verificar a presença de anticorpos contra o Toxoplasma gondii em emas (Rhea americana) e avestruzes (Struthio camelus) criados comercialmente no Brasil. Amostras de sangue de 20 emas e 46 avestruzes (jovens e adultos) foram testadas sorologicamente pela técnica conhecida como teste de aglutinação modificada (MAT) em titulações iniciais de 1:16 para avestruzes e 1:25 para emas. Anticorpos contra T. gondii foram encontrados em 50% (10/20) das emas com títulos variando de 1:25 a 1:6.400. A incidência de anticorpos contra T. gondii em avestruzes foi de 17,4% (8/46) com os títulos oscilando entre 1:16 e 1:256. Aves jovens foram aquelas que apresentaram títulos superiores a 1:200 para T. gondii. Portanto, emas e avestruzes podem ser parasitados por T. gondii, apresentando elevados níveis de anticorpos contra o parasita.

This study aimed to verify the occurrence of antibodies againstToxoplasma gondii in rheas (Rhea americana) and ostriches (Struthio camelus) commercially breeding in Brazil. Blood samples from 20 rheas and 46 ostriches (young and adults) were serologically tested using a technique known as modified agglutination test (MAT) at an initial titration of 1:16 for ostriches and 1:25 for rheas. Antibodies against T. gondii were found in 50% (10/20) of the rheas, with titers ranging from 1:25 to 1:6,400. The incidence of antibodies against T. gondii in ostriches was 17.4% (8/46) with titers ranging from 1:16 to 1:256. Birds showing titers higher than 1:200 forT. gondii were mainly the young ones. Therefore, rheas and ostriches may be parasitized by T. gondii, showing high levels of antibodies against this parasite.