The Effects of Yucca Schidigera Extract and Multi-carbohydrase in Different Crude Protein Diets on Growth Performance, Nutrient Digestibility, Carcass Parameters and Excreta Noxious Gas Contents in Broilers

The scarcity and increase in the price of animal feeds have attracted the attention of nutritionists to address this issue. The inclusion of plant extracts and enzymes to protein-reduced diet could be a feasible strategy to reducing the feed cost. Therefore, the purpose of this study was to assess the impacts of Yucca schidigera extract and multi-carbohydrase in low crude protein (CP) diets of broiler on growth performance, nutrient digestibility, carcass metrics, and noxious gas levels in the excreta. A total of 480, 1-d-old ROSS 308 were randomly allocated into 4 dietary treatments, six replication, and 20 birds/cage. Phase 1, T1(CP 21%, ME 2,969 kcal/kg); T2 (CP 19%, ME 2,863 kcal/kg + 0.02% Yucca); T3 (CP 17%, ME 2,865 kcal/kg + 0.02% Yucca); T4 (CP 17%, ME 2,861 kcal/kg + 0.02% Yucca + 0.1% multi-carbohydrase). Phase 2, T1 (CP 19%, ME 3,086 kcal/kg); T2 (CP 17%, ME 2,977 kcal/kg + 0.02% Yucca); T3 (CP 15%, ME 2,978 kcal/kg + 0.02% Yucca); T4 (CP 15%, ME 2,978 kcal/kg + 0.02% Yucca + 0.1% 0.1% multi-carbohydrase). Although the addition of YS and multi-carbohydrase to the low CP diets on the growth performance did not improve, it revealed the positive result on the nutrient digestibility, carcass parameters, and noxious gas emission. Overall, broilers supplemented with YS 0.02% and multi-carbohydrase (0.1%) demonstrated the best production performances compared to the other treatment groups. Thus, a combination of YS and multi-carbohydrase could be added to the diets with low CP to boost broiler production performance.(AU)

Apparent calcium retention and digestibility coefficients of limestone with different particle sizes in laying hens

Apparent calcium (Ca) retention and digestibility coefficients are affected by limestone particle size in the diet of laying hens. This study aimed to determine the apparent retention and digestibility coefficients of Ca in limestone of different particle sizes in laying hens. The study comprised 288 Lohmann Brown laying hens (50 weeks of age; 1,964 ± 98 g) distributed in a completely randomized experimental design with a 3 × 2 factorial arrangement [three Ca concentrations (10, 20, and 30 g kg-1) × two limestone particle sizes (480 and 1,978 µm)] with eight repetitions per treatment and six birds per experimental unit. The experiment included five days for adaptation and five days for total excreta collection. All birds were slaughtered at the end of the ten days to collect the ileal contents. The total or ileal Ca content was plotted against the Ca of diets concentration using linear regression analysis. The regression line slope represented the apparent retention (CaR) and digestibility coefficients of Ca (CaD) in limestone. There was interaction between Ca concentration in the diet and limestone granulometry on CaD (p = 0.001) and CaR (p < 0.001). The CaD and CaR of fine- and coarse-grained limestone increased linearly with increasing Ca concentrations in the diet. The apparent digestibility coefficients estimated for laying hens fed with fine-grained and coarse-grained limestone were 0.72 and 0.35, respectively. The apparent retention coefficients estimated for laying hens fed fine-grained and coarse-grained limestone were 0.96 and 0.47, respectively.

Performance and Carcass of Broiler Quails Fed Distillers' Dried Grains with Solubles (DDGS)

This study determined the metabolizable energy of DDGS for broiler quails (Experiment I) and evaluated the effect of different dietary levels of DDGS on performance, carcass, organ weight, meat quality, and economic viability (Experiment II). In Experiment I, 72 broiler quails were randomly distributed into two treatments (reference or test diets). The experimental period consisted of 5 days of adaptation, followed by 5 days of total excreta collection. Experimental diets consisted of a reference or a test diet containing 800 g/kg reference diet and 200 g/kg DDGS. In experiment II, 432 unsexed broiler quails were randomly distributed into groups fed six levels of DDGS (0, 50, 100, 150, 200, or 250 g/kg). At 43 days of age, birds were slaughtered and evaluated for carcass yield, organ weight, and meat quality. Apparent metabolizable energy values corrected for nitrogen retention of DDGS were 2,488 and 2,466 kcal/kg for males and females, respectively. In the growth phase and the overall period, feed intake increased linearly (p=0.015 and 0.040) and feed conversion ratio worsened (p=0.038 and 0.001) with the inclusion of DDGS in the diet, respectively. A linear increasing (p=0.001) of gizzard weight was observed with increasing dietary DDGS levels, while the economic variables were affect depending on seasonal feedstocks prices. It is concluded that dietary levels up to 250 g/kg DDGS do not affect growth, carcass characteristics, and meat quality of broiler quails. However, the prices of ingredients in the harvest and off-season period should be considered to determine the level of inclusion of DDGS.(AU)

Identical thermal stress coupled with different temperature and humidity combinations affects nutrient digestibility and gut metabolites of laying hens

The present study investigated whether the same temperature-humidity index (THI) values under different conditions of air temperature and relative humidity (RH) would affect the thermoregulatory, nutritional, and behavioral responses of laying hens. One hundred twenty Hy-Line Brown laying hens (60-weeks-old) were divided equally in two environmental chambers: 26 °C with 70% RH (hRH75) and 30 °C with 30% RH (hT75) for 28 days. The two ambient environments (hRH75 and hT75) had an identical THI value of 75, calculated using an empirical formula for laying hens. Neither hRH75 nor hT75 affected rectal and body-surface temperatures and heart and respiratory rates. The concentration of volatile fatty acids in fecal excreta were altered by the thermal treatments. hT75 vs. hRH75 decreased the proportion of acetate and increased the proportion of propionate in fecal samples. hT75 vs. hRH75 lowered the digestibility of dry matter, crude protein, and neutral detergent fiber at 14 days. Thermal treatments did not affect heat stress-associated behavioral responses including feeding, drinking, panting, and wing elevation at any stage. Laying hens exposed to the same THI at different temperatures and RH exhibit equal physiological responses including rectal and body-surface temperatures, heart and respiratory rates, and behavioral responses. Nonetheless, high-temperature treatment (hT75; 30 °C and 30% RH) vs. low temperature treatment (hRH75; 26 °C and 70% RH) affects nutrient digestibility and gut metabolites, suggesting that there are negligible but discernable responses to temperature in the gut physiology.(AU)

Sources of acid insoluble ash as marker of corn digestibility in broilers / Fontes de cinza insolúvel em ácido como indicador de digestibilidade do milho em frangos de corte

The objective was to evaluate three sources of acid insoluble ash (AIA) (celite, kaolin, and sand), as indicators, to determine the apparent metabolizable energy of corn on a natural matter (AME) basis, dry matter digestibility coefficient (DMDC), and crude protein digestibility coefficient (CPDC) using total and partial excreta collection methods. Two hundred and ten Ross broiler chicks of 18 to 27 days of age were used. Broilers were adapted to experimental the diet for four days, and excreta were collected for 5 days. A reference diet (RD) based on corn and soybean meal was prepared to meet the nutritional requirements of the birds. A test diet was prepared with 40% replacement of RD with corn. The formulated diets were: D1, 99% Reference diet + 1% celite; D2, 59.4% RD + 39.6 % corn + 1% celite; D3, 99% Reference diet + 1% kaolin; D4, 59.4% RD + 39.6 % corn + 1% kaolin; D5, 99% Reference diet + 1% sand; D6, 59.4% RD + 39.6 % corn + 1% sand. The treatments were distributed in a completely randomized design, with six diets and five replicates of seven birds each in a 2x3 factorial arrangement. There were significant interactions for all variables investigated. It was observed that the AME and DMDC values of corn were similar in the two methods of collection, and CPDC values using kaolin and celite makers were similar. However, the AME and CPDC of corn using sand with partial collection method were underestimated by 17.70 and 15.53%, respectively compared to those with the total collection method. The AME values of corn with the collection methods using celite and, the DMDC using celite and sand were significantly different. It was observed that the DMDC using celite and sand provided significantly lower values (4.67 and 5.15%), respectively, and the AME using celite was 2.86% lower than that obtained by total collection. To determine the EMA, DMDC, and CPDC in broilers, it is more efficient to use celiteTM and kaolin as markers with partial collection of excreta. Sand should not be used with partial excreta collection method, because it provides lower values of AME and CPDC compared to with total excreta collection method.(AU)

Objetivou-se avaliar três fontes de cinza insolúvel em ácido (CIA) (celite, caulim, e areia), como indicadores para determinação da energia metabolizável aparente do milho na matéria natural (EMA), coeficiente de digestibilidade da matéria seca (CDMS), e coeficiente de digestibilidade da proteína bruta (CDPB) por meio dos métodos de coleta total e parcial de excretas. Foram utilizados duzentos e dez frangos da linhagem comercial Ross no período de 18 a 27 dias de idade. Os frangos foram adaptados à dieta experimental por quatro dias, e as excretas foram coletadas por 5 dias. Foi formulada uma dieta referência (DR) a base de milho e farelo de soja para atender as exigências nutricionais das aves. A dieta teste com substituição de 40% de milho à DR. As dietas formuladas foram: D1, 99% dieta referência + 1% celite; D2, 59.4% DR + 39.6 % milho + 1% celite; D3, 99% dieta referência + 1% caulim; D4, 59.4% RD + 39.6 % milho + 1% caulim; D5, 99% dieta referência + 1% areia; D6, 59.4% DR + 39.6 % milho + 1% areia. Os tratamentos foram distribuídos em delineamento inteiramente casualizado, com seis dietas e cinco repetições de 7 aves cada em esquema fatorial 2x3. Houve interações significativas para todas as variáveis investigadas. Observouse que os valores de EMA e CDMS do milho são semelhantes pelos dois métodos de coleta utilizando caulim, e CDPB utilizando caulim e celite. Contudo, a EMA e o CDPB do milho usando areia na coleta parcial foram subestimados em 17,70 e 15,53%, respectivamente, em relação à coleta total. Os valores EMA do milho para os métodos de coleta usando celite e, o CDMS usando celite e areia foram significativamente diferentes. Observou-se que o CDMS com celite e areia proporcionou valores significativamente menores (4,67 e 5,15%), respectivamente, e a EMA com celite foi 2,86% menor que o obtido pela coleta total. Para determinar a EMA, CDMS e CDPB em frangos de corte, é mais eficiente usar celiteTM e caulim como indicadores na coleta parcial de excretas. A areia não deve ser usada com o método de coleta parcial de excretas, pois fornece valores menores de EMA e CDPB em comparação com o método de coleta total de excretas.(AU)

Characterization of glutamine synthetase from the ammonium-excreting strain HM053 of Azospirillum brasilense

Abstract Glutamine synthetase (GS), encoded by glnA, catalyzes the conversion of L-glutamate and ammonium to L-glutamine. This ATP hydrolysis driven process is the main nitrogen assimilation pathway in the nitrogen-fixing bacterium Azospirillum brasilense. The A. brasilense strain HM053 has poor GS activity and leaks ammonium into the medium under nitrogen fixing conditions. In this work, the glnA genes of the wild type and HM053 strains were cloned into pET28a, sequenced and overexpressed in E. coli. The GS enzyme was purified by affinity chromatography and characterized. The GS of HM053 strain carries a P347L substitution, which results in low enzyme activity and rendered the enzyme insensitive to adenylylation by the adenilyltransferase GlnE.

Resumo A glutamina sintetase (GS), codificada por glnA, catalisa a conversão de L-glutamato e amônio em L-glutamina. Este processo dependente da hidrólise de ATP é a principal via de assimilação de nitrogênio na bactéria fixadora de nitrogênio Azospirillum brasilense. A estirpe HM053 de A. brasilense possui baixa atividade GS e excreta amônio no meio sob condições de fixação de nitrogênio. Neste trabalho, os genes glnA das estirpes do tipo selvagem e HM053 foram clonados em pET28a, sequenciados e superexpressos em E. coli. A enzima GS foi purificada por cromatografia de afinidade e caracterizada. A GS da estirpe HM053 possui uma substituição P347L que resulta em baixa atividade enzimática e torna a enzima insensível à adenililação pela adenililtransferase GlnE.

Evaluation of Lactobacillus Plantarum Additive on Growth Performance, Excreta Microbiota, Nutrient Digestibility, Gas Emission, and Meat Quality in Ross308-Broilers

The intention of this study was to analyze the effects of Lactobacillus plantarum (L. plantarum) additive with different nutrient density diets on growth performance, excreta microbiota, nutrient digestibility, gas emission, and meat quality in Ross308-broilers. A total of 576 mixed-sex, 1-d old Ross-308 chicks were randomly allocated to one of four treatment groups with 8 replication and 18 chicks/cage. For a period of 35 days, HD and LD group chicks were fed with commercial corn and soybean meal-based basal diet which contains high and low nutrient density diet, respectively. The other treatment groups LP1 and LP2 chicks were fed with LD+ 0.05% and 0.01 % of L. plantarum, respectively. During day 21 and the overall experimental period, the body weight gain of broilers significantly increased (p<0.05) in HD and L. plantarum groups compared to the LD group. On day 35, broilers fed L. plantarum additive had significantly increased (p<0. 05) the nutrient digestibility of dry matter and nitrogen compared to those fed HD and LD diets. Moreover, dietary inclusion of L. plantarum additive had significantly increased (p<0.05) lactobacillus population and decreased (p>0.05) E. coli and ammonium emission. However, the meat quality traits were not affected by experimental diets. In conclusion, we infer that a low-density diet with 0.1% of L. plantarum additive could serve as an excellent alternative feed additive to enhance the performance of broilers.(AU)

Effect of amino acid supplementation and choline chloride for low protein diet on nitrogen efficiency and methane emission of dairy cows / Efeito da suplementação de aminoácidos e cloreto de colina para dieta pobre em proteínas na eficiência de nitrogênio e emissão de metano de vacas leiteiras

Ruminants are one of the largest anthropogenic methane and nitrous oxide emissions. Therefore, the hypothesis was to study the effects of reducing dietary crude protein (CP) level on environmental contaminators when rumen-protected amino acids and choline chloride were supplemented. Sixty Holstein dairy cows were used during the experiment. Test diets were: (1) CD = Control diet with16.2 g of crude protein/ Kg of DM); (2) LM = Low protein diet with 14.2 g of crude protein/ Kg of DM + methionine ; (3) LL = Low protein diet with 14.2 g of crude protein/ Kg of DM + lysine; (4) LML = Low protein diet with 14.2 g of crude protein/ Kg of DM + methionine + lysine; (5) LMLC = Low protein diet with 14.2 g of crude protein/ Kg of DM + methionine + lysine + choline. Dry matter and NDF intake were not different, but the control group received higher CP and ADF compared with other groups (P < 0.05). Fecal CP and ADF of control group were lower (P < 0.05), but no differences were observed for fecal dry matter (DM) and NDF. Milk yield and protein content were higher for LML and LMLC like control group (P < 0.05). Nitrogen intake, urinary N, urinary urea N and total excreta N decreased (P < 0.05) when animals fed low protein. There was no difference in ruminal pH and acetate to propionate ratio, whereas the ruminal ammonia-N decreased with the low protein (P < 0.05). The 120-h gas production test, showed no difference on the kinetics of digestion and in vitro methane emission. However, the inclusion of DMI in the calculations revealed that low protein can reduce (P < 0.05) methane emission. Overall, our findings indicated that low protein can be compensated for by adding rumen-protected amino acids, not only to maintain the animal performance, but also to decrease nitrogen excretion and methane emission.(AU)

Os ruminantes são uma das maiores emissões antropogênicas de metano e óxido nitroso. Portanto, a hipótese foi estudar os efeitos da redução do nível de proteína bruta (PB) na dieta sobre os contaminantes ambientais quando aminoácidos protegidos no rúmen e cloreto de colina foram suplementados. Sessenta vacas leiteiras Holstein foram utilizadas durante o experimento. As dietas teste foram: (1) CD = dieta controle com 16.2 g de proteína bruta / Kg de MS); (2) LM = Dieta pobre em proteínas com 14.2 g de proteína bruta / Kg de DM + metionina; (3) LL = Dieta pobre em proteínas com 14.2 g de proteína bruta / Kg de MS + lisina; (4) LML = Dieta pobre em proteínas com 14.2 g de proteína bruta / Kg de DM + metionina + lisina; (5) LMLC = Dieta pobre em proteínas com 14.2 g de proteína bruta / Kg de DM + metionina + lisina + colina. O consumo de matéria seca e FDN não foi diferente, mas o grupo controle recebeu maior PB e FDA em comparação com os outros grupos (P < 0.05). A PB e FDA fecal do grupo controle foram menores (P < 0.05), mas não foram observadas diferenças para matéria seca (MS) e FDN fecal. A produção de leite e o teor de proteína foram maiores para LML e LMLC como grupo controle (P < 0.05). A ingestão de nitrogênio, N urinário, N urinário urinário e N excreta total diminuíram (P < 0.05) quando os animais foram alimentados com baixa proteína. Não houve diferença no pH ruminal e na relação acetato / propionato, enquanto o N-amônia ruminal diminuiu com o baixo teor de proteína (P < 0.05). O teste de produção de gás de 120 h, não mostrou diferença na cinética de digestão e emissão de metano in vitro. No entanto, a inclusão do CMS nos cálculos revelou que a baixa proteína pode reduzir (P < 0.05) a emissão de metano. No geral, nossos resultados indicaram que o baixo teor de proteína pode ser compensado pela adição de aminoácidos protegidos no rúmen, não apenas para manter o desempenho animal, mas também para diminuir a excreção de nitrogênio e a emissão de metano.(AU)

Nutritional evaluation of chia (Salvia hispanica) seeds and oil in broiler diets

Two experiments were carried with broilers from 29 to 42 days of age for the nutritional evaluation of dietary chia. Thus, the nitrogen-corrected apparent metabolizable energy (AMEn) and the apparent metabolizability coefficients of gross energy and ether extract of chia seeds and oil, toasted soybean grain (TSG), and soybean oil were determined in the experiment I, by total excreta collection method, using 120 broilers. Each experimental diet (reference diet [RD] and four diets with the tested feedstuffs) was evaluated in eight replicates of three broilers. The TSG and chia seeds replaced the RD in 250 g/kg, whereas soybean and chia oils replaced the RD in 100 g/kg. Simultaneously, a second experiment was carried subdivided into two trials. In the performance trial, we evaluated the dietary feedstuffs effects on performance, carcass and cut yields, blood parameters, and activity of lipogenic enzymes. The nutrient metabolizability coefficients and AMEn were evaluated in the metabolism trial. The AMEn values of 37.49, 37.35, 15.85, and 8.43 MJ/kg of dry matter were determined for chia oil, soybean oil, TSG, and chia seeds, respectively (experiment I). In the second experiment, the best feed conversion was observed in broilers fed diets containing chia oil and TSG. However, the diet formulated with chia seeds worsened broiler feed conversion, exhibited the smaller energy value and apparent metabolizability coefficient of the ether extract, and increased the activity of the malic enzyme and serum total cholesterol level. There was no difference for glucose-6-phosphate dehydrogenase activity and high-density lipoprotein cholesterol level. In general, chia oil showed to be efficient in replacing soybean oil in broiler diets.(AU)

Impact of the Supplementation of Exogenous Protease and Carbohydrase on the Metabolizable Energy and Standardized Ileal Amino Acid Digestibility of Soybean Meals in Two Brazilian Regions

This study aimed to evaluate the effects of different exogenous protease and carbohydrase in broiler diets on the nitrogen-corrected apparent metabolizable energy (AMEn) and standardized ileal amino acid digestibility (SIAAD) of soybean meals (SBM) in two Brazilian regions (Minas Gerais-MG and Rio Grande do Sul-RS). The total excreta collection of 528 14-d-old chicks was used to determine AMEn in a completely randomized design in a 2 (SBM MG and RS) x 5 (enzyme A, B, C, D and basal diet) + 1 (reference diet, RD) factorial arrangement, totaling 11 treatments, 8 repetitions, and 6 birds per experimental unit. Two experimental treatments (T1 and T6) without enzyme supplementation formulated with SBM MG and RS were used as negative control (NC). The RD without the inclusion of SBM MG and RS was used to correct the nitrogen balance. To determine the SIAAD, ileal content was collected from of broilers and the same experimental design and treatments of the previous trial were used except for the RD, which was replaced with a nitrogen-free diet (NFD) to quantify the excretion of endogenous amino acids. Soybean meal from MG showed the highest levels (p<0.05) of AME and AMEn (3,188 kcal/kg and 2,700 kcal/kg, respectively) in comparison to SBM RS (3,121 kcal/kg and 2,549 kcal/kg, respectively) and, when supplemented with the exogenous enzyme C, also improved the SIAAD (p<0.05), as compared to other enzymes.(AU)

Effects of Medium Chain Fatty Acid Supplementation in Broiler Diet on Microbiological Quality of Litter

In our experiment, coconut and palm oil supplementation was added to the diet of broiler chickens to prove the hypothesis that medium chain fatty acids (MCFAs) can reduce the occurrence of potential pathogens (Clostridium perfingens, Coliform) in gut microflore and therefore improve bird welfare. Cobb 500 cockerels were divided in five groups. Control birds were fed commercial broiler diet, while birds in the four treatment group diets were supplemented with coconut, palm oil, or a combination of the two, respectively. As a positive control, sunflower oil supplementation was included in the diet of the fifth group. During the 28 days of the study (from 14 to 42 days of life), 5 samplings were scheduled, when excreta samples were taken from the litter to analyse total microbial count and the number of Clostridia, Coliforms, and Salmonella. According to the results of microbiological analysis, coconut oil supplementation led to the continuous decline of Clostridium perfringens numbers until they vanished by the end of the experimental period. A similar but faster decline was found as a result of palm oil and the combined (palm oil+coconut oil) treatment. However, the number of Coliforms and total microbial count changed only slightly by the end of the study. No Salmonella spp. was present in the samples throughout the experiment. Altogether, coconut and palm oil supplementation has a beneficial effect on the microbiological composition of poultry litter.(AU)

Effects of Medium Chain Fatty Acid Supplementation in Broiler Diet on Microbiological Quality of Litter

In our experiment, coconut and palm oil supplementation was added to the diet of broiler chickens to prove the hypothesis that medium chain fatty acids (MCFAs) can reduce the occurrence of potential pathogens (Clostridium perfingens, Coliform) in gut microflore and therefore improve bird welfare. Cobb 500 cockerels were divided in five groups. Control birds were fed commercial broiler diet, while birds in the four treatment group diets were supplemented with coconut, palm oil, or a combination of the two, respectively. As a positive control, sunflower oil supplementation was included in the diet of the fifth group. During the 28 days of the study (from 14 to 42 days of life), 5 samplings were scheduled, when excreta samples were taken from the litter to analyse total microbial count and the number of Clostridia, Coliforms, and Salmonella. According to the results of microbiological analysis, coconut oil supplementation led to the continuous decline of Clostridium perfringens numbers until they vanished by the end of the experimental period. A similar but faster decline was found as a result of palm oil and the combined (palm oil+coconut oil) treatment. However, the number of Coliforms and total microbial count changed only slightly by the end of the study. No Salmonella spp. was present in the samples throughout the experiment. Altogether, coconut and palm oil supplementation has a beneficial effect on the microbiological composition of poultry litter.

Characterization of glutamine synthetase from the ammonium-excreting strain HM053 of Azospirillum brasilense / Caracterização da glutamina sintetase da estipe excretora de amônio HM053 de Azospirillum brasilense

Glutamine synthetase (GS), encoded by glnA, catalyzes the conversion of L-glutamate and ammonium to L-glutamine. This ATP hydrolysis driven process is the main nitrogen assimilation pathway in the nitrogen-fixing bacterium Azospirillum brasilense. The A. brasilense strain HM053 has poor GS activity and leaks ammonium into the medium under nitrogen fixing conditions. In this work, the glnA genes of the wild type and HM053 strains were cloned into pET28a, sequenced and overexpressed in E. coli. The GS enzyme was purified by affinity chromatography and characterized. The GS of HM053 strain carries a P347L substitution, which results in low enzyme activity and rendered the enzyme insensitive to adenylylation by the adenilyltransferase GlnE.

A glutamina sintetase (GS), codificada por glnA, catalisa a conversão de L-glutamato e amônio em L-glutamina. Este processo dependente da hidrólise de ATP é a principal via de assimilação de nitrogênio na bactéria fixadora de nitrogênio Azospirillum brasilense. A estirpe HM053 de A. brasilense possui baixa atividade GS e excreta amônio no meio sob condições de fixação de nitrogênio. Neste trabalho, os genes glnA das estirpes do tipo selvagem e HM053 foram clonados em pET28a, sequenciados e superexpressos em E. coli. A enzima GS foi purificada por cromatografia de afinidade e caracterizada. A GS da estirpe HM053 possui uma substituição P347L que resulta em baixa atividade enzimática e torna a enzima insensível à adenililação pela adenililtransferase GlnE.

Cassava residues in the diet of slow-growing broilers / Resíduos de mandioca na dieta de frangos de crescimento lento

Cassava by-products are abundant and largely unused in familiy agro-industries in the Amazon region, where slow-growing broilers are commonly raised. Thus the incorporation of cassava by-products in broiler feed may provide starch enrichment for better zootechnical performance. We evaluated the use of cassava residues instead of corn in the diet of slow-growing broilers. We determined the chemical composition of cassava scrapings (CS) and cassava starch residue (CSR), and tested the digestibility of the residues in 192 broilers and three treatments: inclusion of 30 g kg-1 CS or CSR and a control without residue, with eight replicates of eight broilers each. Digestibility was assessed through collection of total excreta from 19 to 22 days of age. Apparent and corrected metabolizable energy, and apparent digestibility coefficients of dry matter, crude protein and crude energy were significantly higher for CSR than CS. Therefore, only CSR was used in a performance experiment using 324 broilers 30 to 90 days old, distributed in four treatments (0; 6.8; 13.4 and 20 g kg-1 CSR in feed) with nine replicates of nine broilers each. There was no significant difference among treatments in weight gain, feed intake, yield of carcass, breast and viscera, meat color, luminosity, pH, shear force, cooking-weight loss and drip loss. As there was a significant reduction in feed conversion and thigh and drumstick yield for 20 g kg-1, we suggest the incorporation of CSR up to 13.4 g kg-1.(AU)

Subprodutos da mandioca são abundantes e pouco utilizados nas agroindústrias familiares na Amazônia, onde é comum a criação de frangos de corte de crescimento lento. Portanto, a incorporação de subprodutos de mandioca na alimentação destes frangos pode proporcionar enriquecimento de amido para melhor desempenho zootécnico. Avaliamos a utilização de resíduos da mandioca na alimentação de frangos de crescimento lento em substituição ao milho. Determinamos a composição química da raspa de mandioca (RM) e do resíduo de amido de mandioca (RAM), e testamos a digestibilidade dos resíduos utilizando 192 frangos e três tratamentos: inclusão de 30 g kg-1 RM ou RAM e um controle sem mandioca, com oito repetições de oito frangos cada. Digestibilidade foi determinada por coleta de excretas totais dos 19 aos 22 dias de idade. Energia metabolizável aparente e corrigida e os coeficientes de digestibilidade aparente da matéria seca, proteína bruta e energia bruta foram significativamente maiores para RAM que RM. Assim, apenas RAM foi usado em um experimento de desempenho com 324 frangos de 30 a 90 dias de idade e quatro tratamentos (0; 6,8; 13,4 e 20 g kg-1 RAM na ração), com nove repetições de nove frangos cada. Os tratamentos não diferiram significativamente em ganho de peso, consumo de ração, rendimento de carcaça, peito e vísceras, cor da carne, luminosidade, pH, força de cisalhamento, e perda de peso por cozimento e gotejamento. Como houve redução significativa na conversão alimentar e no rendimento de coxa e sobrecoxa com 20 g kg-1, sugerimos o uso de RAM até 13,4 g kg -1.(AU)

Bacillus coagulans as an alternative to antibiotics in the performance and control of Salmonella Enteritidis in broilers / Bacillus coagulans como alternativa aos antibióticos sobre o desempenho e controle da Salmonella Enteritidis em frangos de corte

The use of antimicrobial growth promoters in broiler feed has been beneficial for improving performance and preventing diseases. However, the indiscriminate use of these products in the feed can result in the development of resistant bacteria, the accumulation of residues in the products, and an imbalance in the microflora of birds. Therefore, it is necessary to evaluate alternatives, such as beneficial microorganisms that improve microbial growth without affecting animal health and product quality. This research aimed to evaluate the supplementation with the probiotic Bacillus coagulans on the performance, carcass characteristics, and health of broilers from seven to 42 days. In total, 720 broilers were used, distributed in a randomized block design with six treatments and eight replicates. The evaluated treatments were as follows: Control ration (RC); PROB1 (Probiotic 400 g/t); PROB2 (Probiotic 400 g/t until 21 days and 200 g/t from 22 to 42 days); RC + antibiotic; RC + Salmonella inoculation; PROB1 + Salmonella inoculation. The treatments did neither influence feed intake, carcass yield, and cuts nor the incidence of injuries to the chest, hock, and footpad. Weight gain and feed conversion were better in birds that received antibiotic or probiotic diets. There was an incidence of Salmonella in the challenges excreta at42 days only in the treatment with challenge without adding probiotics. We conclude that the probiotic Bacillus coagulans can be used as an alternative to antibiotics in the diet of broilers as it facilitates similar performance and is efficient in the control of Salmonella Enteritidis.

A utilização de promotores de crescimento antimicrobianos na alimentação de frangos de corte tem sido benéfica para melhoria do desempenho e para prevenção de doenças. Porém, o uso indiscriminado destes produtos nas rações pode resultar em desenvolvimento de bactérias resistentes, acúmulo de resíduos nos produtos e desequilíbrio da microflora das aves. Portanto, torna-se necessário avaliar alternativas como microrganismos benéficos que melhorem o crescimento microbiano, sem afetar a saúde do animal e a qualidade dos seus produtos. Objetivou-se com esta pesquisa avaliar a suplementação do probiótico Bacillus coagulans sobre o desempenho, características de carcaça e saúde de frangos de corte de 7 a 42 dias. Utilizou-se 720 frangos de corte distribuídos em delineamento em blocos casualizados, com seis tratamentos e oito repetições. Os tratamentos avaliados foram: Controle; PROB1 (Probiótico 400 g/t); PROB2 (Probiótico 400 g/ton até os 21 dias e 200 g/t dos 22 aos 42 dias); Controle + antibiótico; Controle + inoculação de Salmonella; PROB1 + inoculação de Salmonella. Os tratamentos não influenciaram o consumo de ração, rendimento de carcaça e cortes e a incidência de lesões no peito, jarrete e coxim plantar. O ganho de peso e a conversão alimentar foram melhores nas aves que receberam rações com antibiótico ou probiótico. Houve incidência de Salmonella nas excretas aos 42 dias somente no tratamento com desafio sem adição de probiótico. Conclui-se que o probiótico Bacillus coagulans pode ser usado como alternativa ao antibiótico na ração de frangos de corte, pois proporciona desempenho semelhante e é eficiente no controle da Salmonella Enteritidis

Characterization of glutamine synthetase from the ammonium-excreting strain HM053 of Azospirillum brasilense / Caracterização da glutamina sintetase da estipe excretora de amônio HM053 de Azospirillum brasilense

Glutamine synthetase (GS), encoded by glnA, catalyzes the conversion of L-glutamate and ammonium to L-glutamine. This ATP hydrolysis driven process is the main nitrogen assimilation pathway in the nitrogen-fixing bacterium Azospirillum brasilense. The A. brasilense strain HM053 has poor GS activity and leaks ammonium into the medium under nitrogen fixing conditions. In this work, the glnA genes of the wild type and HM053 strains were cloned into pET28a, sequenced and overexpressed in E. coli. The GS enzyme was purified by affinity chromatography and characterized. The GS of HM053 strain carries a P347L substitution, which results in low enzyme activity and rendered the enzyme insensitive to adenylylation by the adenilyltransferase GlnE.(AU)

A glutamina sintetase (GS), codificada por glnA, catalisa a conversão de L-glutamato e amônio em L-glutamina. Este processo dependente da hidrólise de ATP é a principal via de assimilação de nitrogênio na bactéria fixadora de nitrogênio Azospirillum brasilense. A estirpe HM053 de A. brasilense possui baixa atividade GS e excreta amônio no meio sob condições de fixação de nitrogênio. Neste trabalho, os genes glnA das estirpes do tipo selvagem e HM053 foram clonados em pET28a, sequenciados e superexpressos em E. coli. A enzima GS foi purificada por cromatografia de afinidade e caracterizada. A GS da estirpe HM053 possui uma substituição P347L que resulta em baixa atividade enzimática e torna a enzima insensível à adenililação pela adenililtransferase GlnE.(AU)

Characterization of glutamine synthetase from the ammonium-excreting strain HM053 of Azospirillum brasilense / Caracterização da glutamina sintetase da estipe excretora de amônio HM053 de Azospirillum brasilense

Glutamine synthetase (GS), encoded by glnA, catalyzes the conversion of L-glutamate and ammonium to L-glutamine. This ATP hydrolysis driven process is the main nitrogen assimilation pathway in the nitrogen-fixing bacterium Azospirillum brasilense. The A. brasilense strain HM053 has poor GS activity and leaks ammonium into the medium under nitrogen fixing conditions. In this work, the glnA genes of the wild type and HM053 strains were cloned into pET28a, sequenced and overexpressed in E. coli. The GS enzyme was purified by affinity chromatography and characterized. The GS of HM053 strain carries a P347L substitution, which results in low enzyme activity and rendered the enzyme insensitive to adenylylation by the adenilyltransferase GlnE.

A glutamina sintetase (GS), codificada por glnA, catalisa a conversão de L-glutamato e amônio em L-glutamina. Este processo dependente da hidrólise de ATP é a principal via de assimilação de nitrogênio na bactéria fixadora de nitrogênio Azospirillum brasilense. A estirpe HM053 de A. brasilense possui baixa atividade GS e excreta amônio no meio sob condições de fixação de nitrogênio. Neste trabalho, os genes glnA das estirpes do tipo selvagem e HM053 foram clonados em pET28a, sequenciados e superexpressos em E. coli. A enzima GS foi purificada por cromatografia de afinidade e caracterizada. A GS da estirpe HM053 possui uma substituição P347L que resulta em baixa atividade enzimática e torna a enzima insensível à adenililação pela adenililtransferase GlnE.

Cinomose em canídeos silvestres no Brasil / Distemper in wild canids in Brazil

A cinomose é uma doença viral multissistêmica causada por um Morbillivirus. No Brasil, existem seis espécies de canídeos silvestres vulneráveis a essa enfermidade. Dessa forma, este trabalho tem como objetivo apresentar uma revisão sobre a situação da cinomose em canídeos silvestres no Brasil e os impactos causados na fauna brasileira. A transmissão do vírus ocorre através do contato com amostras contaminadas, a exemplo dos aerossóis, excretas e secreções de indivíduos infectados. Os sinais clínicos mais prevalentes são de ordem neurológica, entretanto, também podem ser identificadas manifestações respiratórias, cutâneas e gastrointestinais. Portanto, o diagnóstico consiste na avaliação da sintomatologia apresentada em conjunto com testes específicos, como isolamento viral, ELISA, imunofluorescência e RT-PCR. Atualmente, não existe tratamento específico. Desta forma, são realizados apenas cuidados paliativos. Os grandes carnívoros são os mamíferos mais ameaçados do mundo, sobretudo, em consequência dos impactos causados pela redução do habitat natural, associada à expansão territorial humana. As epidemias também justificam as altas taxas de mortalidades desses animais, o que pode estar relacionado com comportamentos sociais e de farejamento, assim como o crescente contato entre animais silvestres e domésticos devido à urbanização e à proximidade genética que os canídeos silvestres têm com os cães domésticos, tornando-os suscetíveis às infecções. Visto que a cinomose é uma patologia emergente em populações de carnívoros silvestres e que a presença de cães domésticos não vacinados em áreas de conservação representa um grande risco de contaminação, conclui-se que a não vacinação está diretamente associada à perpetuação do vírus no meio selvagem.

Distemper is a multisystem viral disease caused by a Morbillivirus. In Brazil, there are six species of wild canids, vulnerable to this disease. Therefore, the present work aims to develop a review on the situation of distemper in wild canids in Brazil and the impacts caused on the Brazilian fauna. The virus transmission occurs through contact with contaminated samples, such as aerosols, excreta, and secretions from infected individuals. The most prevalent clinical signs are neurological; however, respiratory, cutaneous and gastrointestinal manifestations can also be identified. Thus, the diagnosis consists of evaluating the symptoms presented together with specific tests, such as viral isolation, ELISA, immunofluorescence, and RT-PCR. Currently, there is no specific treatment. Therefore, only palliative care is performed. Large carnivores are the most threatened mammals in the world, mainly as a result of the impacts caused by the reduction of natural habitat, associated with human territorial expansion. Epidemics also justify the high mortality rates of these animals, which may be related to social and sniffing behaviors, as well as the increasing contact between wild and domestic animals due to urbanization and the genetic proximity that wild canids have with domestic dogs, making them susceptible to infections. Since distemper is an emerging pathology in populations of wild carnivores and the presence of unvaccinated domestic dogs in conservation areas represents a great risk of contamination, it is concluded that non-vaccination is directly associated with the perpetuation of the virus in the wild.

Inclusion of kaolin in the diet of brown egg layers at the end of the production cycle / Caulim na alimentação de poedeiras semipesadas ao final do ciclo produtivo

ABSTRACT: This study investigated the inclusion of kaolin levels in the diet of brown egg layers at the end of the production cycle. A completely randomized design involved the distribution of 288 brown egg layers into six treatments of eight replications, with six birds per replication. When the birds reached the age of 63 weeks, the feeding of the experimental diets began. Diets differed by the inclusion of increasing levels of kaolin: Control (no additive), and the inclusion of 1%, 2%, 3%, 4%, and 5% kaolin. The performance, egg quality, intestinal morphometry, and excreta moisture were evaluated. The inclusion of kaolin promoted improvement in the jejunum villus height, enabling less feed intake; however, there were no significant differences in egg quality. The excreta moisture decreased linearly as the kaolin level in the diet increased. The inclusion of 5% kaolin in the diet of brown egg layers at the end of the production cycle improved intestinal morphometry and the quality of excreta through a reduction of moisture.

RESUMO: O objetivo deste trabalho foi investigar a inclusão de níveis de caulim na dieta de poedeiras semipesadas ao final do ciclo de produção. Foram utilizadas 288 galinhas semipesadas distribuídas em delineamento inteiramente casualizado com seis tratamentos de oito repetições, contendo seis aves por repetição. Quando as aves atingiram a idade de 63 semanas, foi iniciada a alimentação com as dietas experimentais. As dietas diferiam entre si pela inclusão de níveis crescentes de caulim: controle (sem aditivo); e a inclusão de 1, 2, 3, 4 e 5% de caulim na dieta. Foram avaliados o desempenho, a qualidade dos ovos, a morfologia intestinal e a umidade das excretas. A inclusão de caulim promoveu melhora na altura das vilosidades do jejuno, possibilitando menor consumo de ração. Não houve diferenças significativas para a qualidade dos ovos. A umidade das excretas diminuiu com o aumento do nível de caulim na dieta, respondendo de forma linear. A inclusão de caulim ao nível de 5% nas rações de poedeiras semipesadas ao final do ciclo de produção melhorou a morfometria intestinal e a qualidade dos excrementos por meio da redução de sua umidade.

Monitoramento hormonal não invasivo em aves uma revisão / Non-invasive hormonal monitoring in birds a review

Para espécies silvestres, a coleta de amostras para monitorar o estresse e a função reprodutiva sempre foi um desafio. Coletas de sangue em animais silvestres são difíceis de serem realizadas, pois sempre exige a contenção física do animal, seguida ou não de sedação ou anestesia, que acaba dificultando ou impossibilitando coletas muito frequentes, tanto pelo estresse que causa ao animal como pelos cuidados clínicos que se dever ter no uso dessas drogas. As técnicas de dosagens hormonais não invasivas vieram como uma boa opção, realizando a análise destes hormônios ou seus metabólitos. Estes são excretados nas fezes, urina, excretas, pele, pelos ou saliva, permitindo o acompanhamento por longos períodos, pois em muitos casos, não exigem manipular o animal. As amostras mais utilizadas são fezes e urina e, no caso das aves, excretas. As técnicas mais utilizadas são os ensaios imunológicos, utilizado isótopos radioativos (radioimunoensaio) ou enzimas (enzimoimunoensaio). Nesta revisão, são apresentadas as principais vantagens da dosagem não invasiva, focando principalmente seu uso em aves, utilizando excretas e abordando também as principais técnicas de dosagem.(AU)

For wild species, sampling for monitoring stress and reproductive function has always been a challenge. Blood collections in wild animals are difficult to perform because they often require physical restraint of the animal, which causes stress, or at least sedation or anesthesia, which makes it difficult or impossible for frequent collections. Noninvasive hormone monitoring techniques came as a good option, performing analysis of these hormones or their metabolites. These are excreted in feces, urine, excreta, hair or saliva, allowing the collection for long periods, since in many cases they do not require to manipulate the animal. The most commonly used samples are feces and urine, and in the case of birds, excreta. The most commonly used techniques are immunological assays, radioactive isotopes (radioimmunoassay) or enzymes (enzymeimmunoassay). In this review, the main advantages of noninvasive hormonal monitoring are presented, focusing more on their use in birds, using excreta and also addressing the main dosage techniques.(AU)