Determination of the Gastrointestinal Passage Rate Using Dexa Technology and Barium Sulfate As a Marker in Japanese Quails

The objective of this study was to characterize the dynamics of food passage in the gastrointestinal tract (GIT) of Japanese quail. A randomized design was used with four treatments and four experimental units with one bird each, nine of which were measured in time. The ingredients used were albumin, starch, cellulose, and soybean oil. Suspensions containing barium sulfate and saline were prepared, except for soybean oil. For each bird, 2.5 mL of the suspension was administered directly to the crop. Dual-energy absorptiometry (DEXA) was used to quantify the passage of food. The birds were sedated and maintained under inhalation anesthesia during the scan. Measurements were taken at intervals of 0.5, 1, 2, 4, 6, 8, 10, 12, and 24 h. The variables identified were passage time, first quality, and the average time of each variable. Based on these results, the ingredients may show differences in dynamic passing on the Japanese quail GIT. The duration of the first attempt was 32 min, ranging from 21 to 44 min. The average time value of food choice was close to 10.8 h and varied according to the ingredient from 8.45-12.16 h. Among the variables, soybean oil presented values ​​that denote a fast passage in the GIT, while albumin presented values ​​that denote a slower passage. The dynamics of food passage in the GIT of Japanese quails varies according to the chemical composition of the ingredients.(AU)

Effect of Dietary Tetramethylpyrazine on Egg Production, Nutrient Retention and Cecal Bacterial Diversity in Aged Laying Hens

This study aimed to investigate the effect of tetramethylpyrazine (TMP) supplementation on egg production, nutrient retention and cecal microbiota diversity using 288 commercial Hy-Line brown hens as of wk 75 to 86. Four treatments consisted of TMP addition at 0 (control, basal diet), 100, 150 and 200 mg/kg of diet. The results showed that diets supplemented with TMP addition improved egg-laying rate as of wk 77 compared to the control, which led to an increase (p<0.001) of egg mass by 97-225 g/hen throughout the whole trial, and a linear increase (p=0.003) of egg mass to the incremental TMP doses was found. At wk 86, the apparent digestibilities of dry matter and crude protein were enhanced (p<0.05), exhibiting consistent linear increases (p≤0.033) with the TMP doses. However, TMP did not cause alpha and beta diversity of cecal microbiota. The results suggest that TMP can be an additive to improve egg production and nutrient digestibility of aged laying hens.(AU)

Method for the physical characterization of substrates using centrifugation

The characterization of substrate properties supports the correct choice of components and directs management decisions in container cultivation. There are several systems of analysis, however, the routine procedures to determine the water retention curve (WRC) are time consuming and inaccurate. This study proposed a reproducible, less time-consuming, and easy to perform method for physical characterization of substrates. We used Sphagnum peat, coconut powder, carbonized rice husk, expanded vermiculite, and expanded clay in isolation. The WRC was obtained at tensions 0, 10, 50, and 100 hPa using the method of Büchner funnel, the European standard (CEN-EN13041), and by the centrifugation method of samples. In centrifugation, tensions were simulated by combining the angular velocity, sample height, and radius measured from the sample outermost point to the central point of the centrifuge. Three rotations were applied (230; 520 and 730 rpm), testing the centrifugation time for each tension and then the volumetric water content was compared between the methods. The results showed a positive correlation (p < 0.001) between the centrifugation and standard methods, considering that the centrifugation time required for moisture stabilization varied according to the material analyzed and the tension applied. However, the time required to obtain a report was reduced by half. Sample centrifugation is a promising method, ensuring that the tensile force actually acts on the entire sample to determine the water retention curve of the substrate also reducing the duration of the analyses.

Dieta prática com substituição total da farinha de peixe por farelo de soja para tilápia-do-nilo: desempenho de crescimento e efeitos na saúde / Practical diet with total replacement of fishmeal by soybean meal for Nile tilapia: growth performance and health effects

This study aimed to evaluate the growth performance and animal health in juveniles of Nile tilapia (Oreochromis niloticus) fed a practical diet with total replacement of fishmeal (FM) by soybean meal, as well the effect on survival, following pathogenic challenge with Aeromonas hydrophila. Two hundred juveniles of Nile tilapia were stored in 8 tanks (800 L). The experiment consisted of two treatments: a commercial diet formulated with FM (control) and a practical diet with total replacement of FM by soybean meal (SM). The variables of water quality, zootechnical and hematological parameters were measured. In addition, at the end of the experiment, the fish were submitted to a challenge with A. hydrophila. Higher cost per kg of fish was obtained in the control treatment (with FM). N retention was higher in fish fed a diet without FM, while hematological, immunological parameters and survival after the experimental challenge did not differ between treatments. It is possible to reduce dietary costs by replacing FM with SM without affecting growth performance or animal health, in addition to benefiting the environment by reducing the excretion of N in water.

O objetivo deste estudo foi avaliar o desempenho de crescimento e saúde em juvenis de tilápia-do-nilo (Oreochromis niloticus) alimentados com dieta prática com substituição total da farinha de peixe (FP) por farelo de soja (FS), bem como o efeito na sobrevivência, após desafio patogênico com Aeromonas hydrophila. Duzentos juvenis de tilápia-do-nilo foram alojados em 8 tanques (800 L). O experimento consistiu de dois tratamentos: dieta comercial formulada com FP (controle) e dieta prática com substituição total do FP pelo FS. Foram mensuradas as variáveis de qualidade da água, parâmetros zootécnicos e hematológicos. Além disso, ao final do experimento, os peixes foram submetidos a um desafio com A. hydrophila. Maior custo por kg de peixe foi obtido no tratamento controle (com FP). A retenção de N foi maior nos peixes alimentados com dieta sem FP, enquanto os parâmetros hematológicos, imunológicos e a sobrevivência após o desafio experimental não diferiram entre os tratamentos. É possível reduzir os custos dietéticos substituindo a FP pelo FS sem afetar o desempenho do crescimento e a saúde do animal, além de beneficiar o meio ambiente ao reduzir a excreção de N na água.

Financial losses related to placental retention in dairy herds in Turkey / Perdas financeiras relacionadas à retenção placentária em rebanhos leiteiros na Turquia

This study aimed to calculate the financial losses related to placental retention (PR) in dairy cattle in Turkey taking into consideration the previous study results in three different geographical regions and 87 herds of Turkey. The mean prevalence of PR in dairy herds was assumed to be 5.6% (4.1-6.7%). Direct (milk losses, treatment, and involuntary culling) and indirect losses (extended calving interval and extra insemination) were calculated. In the financial analysis, direct and indirect losses were calculated according to the current prices of 2022. As a result, the financial losses per infected dairy cattle were estimated at $ 249.7 (624 Lt milk eq.). A total of 67.7% ($173) of these resulted from direct losses, and the remainder 32.3% ($82.5), were indirect losses. PR was responsible for a total of $92 million (ranged from $67-110 million) losses, which equates to 1.2% (0.8-1.14%) of the annual milk production in Turkey. In conclusion, magnitude of PR-related losses will provide evidence-based decision support to the farmers and policymakers when determining the priorities for disease mitigation and control strategies.

Este estudo teve como objetivo calcular as perdas financeiras relacionadas à placental retention (PR) em gado leiteiro na Turquia. Considerando os resultados do estudo anterior em três diferentes regiões geográficas e 87 rebanhos da Turquia. A prevalência média de SR em rebanhos leiteiros foi assumida em 5,6% (4,1-6,7%). Na análise financeira foram calculadas as perdas diretas (perdas de leite, tratamento e descarte involuntário) e indiretas (intervalo de partos prolongado e inseminação extra). Na análise financeira, as perdas diretas e indiretas foram calculadas de acordo com os preços atuais de 2022. Como resultado, as perdas financeiras por gado leiteiro infectado foram estimadas em $249,7 (624 Lt leite eq.). Um total de 67,7% ($173) destes resultou de perdas diretas, e os 32,3% restantes ($82,5), foram perdas indiretas. PR foi responsável por um total de $ 92 milhões (variou de $ 67-110 milhões) de perdas, o que equivale a 1,2% (0,8-1,14%) da produção anual de leite na Turquia. Em conclusão, a magnitude das perdas relacionadas ao PR fornecerá suporte à decisão baseado em evidências para os agricultores e formuladores de políticas ao determinar as prioridades para estratégias de mitigação e controle de doenças.

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)

Mitsuokella Jalaludinii Supplementation Improved Nutrient Utilization of Broilers Fed Low-Available Phosphorus Diet

Phytase enzyme is supplemented to poultry feed to improve phosphorus (P) availability. Mitsuokella jalaludinii, bacteria isolated from the rumen of cattle, has been reported as a cheaper alternative source of phytase. As much nutrients are trapped within the phytate complex, we hypothesized that the supplementation of M. jalaludinii phytase to poultry feed would enhance nutrient utilization by poultry. In the current study, the efficacy of freeze-dried M. jalaludinii cells (Mj) as feed supplement for broilers fed low-available phosphorus (low-aP) diet was evaluated. Day-old male Cobb raised in battery cages were assigned to three treatment groups [normal-available phosphorus diet with heat-deactivated Mj (DMj); low-aP diet with DMj; and low-aP diet with Mj], each consisting of four replicates (10 birds per replicate) for a 3-weeks feeding period. Feed intake was recorded daily from day 1-21, whereas broilers were weighted at day 1, 7, 14, and 21. Total excreta were collected at day 11-13 and 18-20. At day 21, twelve broilers from each treatment group were slaughtered to collect plasma and tibia. The results showed that Mj significantly enhanced broilers live weight and feed conversion ratio compared to the control groups (p 0.05). Supplementation with Mj have also enhanced the level of P, Ca, Mn, Cu, and Zn in the sera; and Ca and Mn in the tibia at day 18-20 sampling period (p 0.05). As Mj supplementation can enhance nutrient utilization particularly in broilers fed with low-aP diet, it could provide the market with another option in improving broilers growth rate at a lower cost.(AU)

Mitsuokella Jalaludinii Supplementation Improved Nutrient Utilization of Broilers Fed Low-Available Phosphorus Diet

Phytase enzyme is supplemented to poultry feed to improve phosphorus (P) availability. Mitsuokella jalaludinii, bacteria isolated from the rumen of cattle, has been reported as a cheaper alternative source of phytase. As much nutrients are trapped within the phytate complex, we hypothesized that the supplementation of M. jalaludinii phytase to poultry feed would enhance nutrient utilization by poultry. In the current study, the efficacy of freeze-dried M. jalaludinii cells (Mj) as feed supplement for broilers fed low-available phosphorus (low-aP) diet was evaluated. Day-old male Cobb raised in battery cages were assigned to three treatment groups [normal-available phosphorus diet with heat-deactivated Mj (DMj); low-aP diet with DMj; and low-aP diet with Mj], each consisting of four replicates (10 birds per replicate) for a 3-weeks feeding period. Feed intake was recorded daily from day 1-21, whereas broilers were weighted at day 1, 7, 14, and 21. Total excreta were collected at day 11-13 and 18-20. At day 21, twelve broilers from each treatment group were slaughtered to collect plasma and tibia. The results showed that Mj significantly enhanced broilers live weight and feed conversion ratio compared to the control groups (p 0.05). Supplementation with Mj have also enhanced the level of P, Ca, Mn, Cu, and Zn in the sera; and Ca and Mn in the tibia at day 18-20 sampling period (p 0.05). As Mj supplementation can enhance nutrient utilization particularly in broilers fed with low-aP diet, it could provide the market with another option in improving broilers growth rate at a lower cost.

Mapping a hydrophysical soil property through a comparative analysis of local and global scale approximations

Current available soil information allows building baselines to improve research, such as sustainable resource management; however, its use requires analysis of accuracy and precision that describes specific variables on local and global scales. Therefore, this study evaluated differences in the spatial distribution of water retention capacity (WRC) of the soil at a depth of 0.3 m, calculated from local general soil surveys and the global gridded soil information system (SoilGrids), using detailed or semi-detailed soil surveys as a reference, in two regions of Colombia (A and B). The qualitative and statistical analyses evaluated differences in WRC surfaces generated by the information sources. Neither information sources described WRC accurately, achieving correlations between −0.15 and 0.49 and average absolute errors between 9.65 and 19.52 mm for zones A and B, respectively. However, studies on the local scale remain within the ranges observed in the most detailed local studies. The use of products on the global scale is subject to regional analyses; nevertheless, they can be included as a covariate in digital soil mapping studies on more detailed scales.

Mapping a hydrophysical soil property through a comparative analysis of local and global scale approximations

Current available soil information allows building baselines to improve research, such as sustainable resource management; however, its use requires analysis of accuracy and precision that describes specific variables on local and global scales. Therefore, this study evaluated differences in the spatial distribution of water retention capacity (WRC) of the soil at a depth of 0.3 m, calculated from local general soil surveys and the global gridded soil information system (SoilGrids), using detailed or semi-detailed soil surveys as a reference, in two regions of Colombia (A and B). The qualitative and statistical analyses evaluated differences in WRC surfaces generated by the information sources. Neither information sources described WRC accurately, achieving correlations between −0.15 and 0.49 and average absolute errors between 9.65 and 19.52 mm for zones A and B, respectively. However, studies on the local scale remain within the ranges observed in the most detailed local studies. The use of products on the global scale is subject to regional analyses; nevertheless, they can be included as a covariate in digital soil mapping studies on more detailed scales.(AU)

Birds of prey pellet analysis: morphometry and consumption interval of captive Accipitridae species / Análise de pelotas de aves de rapina: morfometria e intervalo de consumoem espécies da família Accipitridae em cativeiro

Pellet production is a typical characteristic of the digestive physiology of birds of prey. Alimentary pellets consist of non-digested parts of prey, such as fur, feathers, bones, and parts of insects, that are regurgitated. Obtained dietary samples, such as regurgitated pellets, can noninvasively contribute to the knowledge of the anatomical alimentary channel and the digestive efficiency of birds of prey. The aim of this study was to evaluate the pellet morphometry and meal-to-pellet interval (MPI) of the Accipitridae family subjected to two experimental diets. Heterospizias meridionalis, Rupornis magnirostris, and Geranoaetus albicaudatus were subjected to (1) mice and (2) quail pre-treating diets. Both diets were individually weighed and provided by removing excess feathers, skin, and some viscera. After consumption, the MPI was noted and, immediately after collection, the pellets were carefully weighed on a precision balance and morphometric measurements were taken using a caliper. Pellet weight, length, width, height, and volume were higher when raptors consumed mice. Differences in morphometric characteristics were found between species. Heterospizias meridionalis presented the highest values for the morphometric parameters evaluated. Consumption of mice increased the frequency of regurgitation and the number and weight of pellets egested, indicating that by providing this type of food, we can underestimate the consumption by birds if we do not consider nutritional losses by the pellets when calculating diets. Pellet assessment and MPI are important tools for monitoring the health and nutritional aspects of birds of prey.

A produção de pelotas é uma característica típica da fisiologia digestiva de aves de rapina. As pelotas alimentares consistem em partes não digestíveis de presas como peles, penas, ossos e partes de insetos que são expelidos. A obtenção de amostras como as pelotas podem colaborar de forma não invasiva com o conhecimento da anatomia do canal alimentar e eficiência digestiva de rapinantes. O objetivo desse estudo foi avaliar a morfometria e o intervalo entre consumo e egestão de pelotas (ICP) em indivíduos da família Accipitridae. Heterospizias meridionalis, Rupornis magnirostris e Geranoaetus albicaudatus foram submetidos a dietas pré processadas com(1) camundongos e (2) codornas. Ambas as dietas foram individualmente pesadas e fornecidas após a remoção do excesso de penas, pele e algumas vísceras. Após o consumo, o ICP foi calculado e imediatamente após a coleta as pelotas foram pesadas e avaliadas quanto a medidas morfométricas com a ajuda de um paquímetro. O peso, comprimento, largura, altura e volume das pelotas foram maiores quando as aves consumiram ratos. Diferenças morfométricas foram encontradas entre as espécies. Heterospizias meridionalis apresentaram os valores mais altos para os parâmetros morfométricos avaliados. O consumo de camundongos aumentou a frequência de egestão, o número e o peso das pelotas, indicando que, ao fornecer este tipo de alimento, podemos subestimar o consumo pelas aves se não considerarmos as perdas nutricionais pelas pelotas ao calcular as dietas. A avaliação de pelotas e ICP são ferramentas importantes para monitorar os aspectos sanitários e nutricionais em rapinantes.

Birds of prey pellet analysis: morphometry and consumption interval of captive Accipitridae species / Análise de pelotas de aves de rapina: morfometria e intervalo de consumoem espécies da família Accipitridae em cativeiro

Pellet production is a typical characteristic of the digestive physiology of birds of prey. Alimentary pellets consist of non-digested parts of prey, such as fur, feathers, bones, and parts of insects, that are regurgitated. Obtained dietary samples, such as regurgitated pellets, can noninvasively contribute to the knowledge of the anatomical alimentary channel and the digestive efficiency of birds of prey. The aim of this study was to evaluate the pellet morphometry and meal-to-pellet interval (MPI) of the Accipitridae family subjected to two experimental diets. Heterospizias meridionalis, Rupornis magnirostris, and Geranoaetus albicaudatus were subjected to (1) mice and (2) quail pre-treating diets. Both diets were individually weighed and provided by removing excess feathers, skin, and some viscera. After consumption, the MPI was noted and, immediately after collection, the pellets were carefully weighed on a precision balance and morphometric measurements were taken using a caliper. Pellet weight, length, width, height, and volume were higher when raptors consumed mice. Differences in morphometric characteristics were found between species. Heterospizias meridionalis presented the highest values for the morphometric parameters evaluated. Consumption of mice increased the frequency of regurgitation and the number and weight of pellets egested, indicating that by providing this type of food, we can underestimate the consumption by birds if we do not consider nutritional losses by the pellets when calculating diets. Pellet assessment and MPI are important tools for monitoring the health and nutritional aspects of birds of prey.(AU)

A produção de pelotas é uma característica típica da fisiologia digestiva de aves de rapina. As pelotas alimentares consistem em partes não digestíveis de presas como peles, penas, ossos e partes de insetos que são expelidos. A obtenção de amostras como as pelotas podem colaborar de forma não invasiva com o conhecimento da anatomia do canal alimentar e eficiência digestiva de rapinantes. O objetivo desse estudo foi avaliar a morfometria e o intervalo entre consumo e egestão de pelotas (ICP) em indivíduos da família Accipitridae. Heterospizias meridionalis, Rupornis magnirostris e Geranoaetus albicaudatus foram submetidos a dietas pré processadas com(1) camundongos e (2) codornas. Ambas as dietas foram individualmente pesadas e fornecidas após a remoção do excesso de penas, pele e algumas vísceras. Após o consumo, o ICP foi calculado e imediatamente após a coleta as pelotas foram pesadas e avaliadas quanto a medidas morfométricas com a ajuda de um paquímetro. O peso, comprimento, largura, altura e volume das pelotas foram maiores quando as aves consumiram ratos. Diferenças morfométricas foram encontradas entre as espécies. Heterospizias meridionalis apresentaram os valores mais altos para os parâmetros morfométricos avaliados. O consumo de camundongos aumentou a frequência de egestão, o número e o peso das pelotas, indicando que, ao fornecer este tipo de alimento, podemos subestimar o consumo pelas aves se não considerarmos as perdas nutricionais pelas pelotas ao calcular as dietas. A avaliação de pelotas e ICP são ferramentas importantes para monitorar os aspectos sanitários e nutricionais em rapinantes.(AU)

Phosphorus utilization in broilers fed with diets supplemented with different feed ingredients

A reliable determination of endogenous phosphorus (P) excretion is required to measure P utilization in chickens accurately. The objective of this study was to investigate phosphorus (P) retention in broilers fed diets formulated with different feed ingredients. Sixty-four 15-d old broiler chicks were fed diets in which part of the dietary P was provided from dicalcium phosphate, maize, barley or soybean. Level of supplementation of each ingredient was calculated to provide two levels of total P (4.5 or 5.0 g kg1 feed). Birds received a single injection of 3 MBq of 32P to determine endogenous P excretion using the isotope dilution technique. Four days after injection, blood and excreta were collected for analysis of inorganic and radioactive P. There were no differences among diets in total (p = 0.37) or endogenous (p = 0.65) P excretion or in P retention (p = 0.37) regardless of the supplemental feed material used in each diet. Daily P retention was increased (p = 0.004) as P intake increased, but the proportion of P ingested that was retained was not affected (p = 0.23) by the level of dietary P. The use of an isotopic tracer allows for accurate estimation of endogenous P in excreta, ranging from 0.24 to 0.42 mg P g1 dry matter intake. The retention of P in growing chickens was not changed when 10-20 % of total P was provided by maize, barley or soybean.

Phosphorus utilization in broilers fed with diets supplemented with different feed ingredients

A reliable determination of endogenous phosphorus (P) excretion is required to measure P utilization in chickens accurately. The objective of this study was to investigate phosphorus (P) retention in broilers fed diets formulated with different feed ingredients. Sixty-four 15-d old broiler chicks were fed diets in which part of the dietary P was provided from dicalcium phosphate, maize, barley or soybean. Level of supplementation of each ingredient was calculated to provide two levels of total P (4.5 or 5.0 g kg1 feed). Birds received a single injection of 3 MBq of 32P to determine endogenous P excretion using the isotope dilution technique. Four days after injection, blood and excreta were collected for analysis of inorganic and radioactive P. There were no differences among diets in total (p = 0.37) or endogenous (p = 0.65) P excretion or in P retention (p = 0.37) regardless of the supplemental feed material used in each diet. Daily P retention was increased (p = 0.004) as P intake increased, but the proportion of P ingested that was retained was not affected (p = 0.23) by the level of dietary P. The use of an isotopic tracer allows for accurate estimation of endogenous P in excreta, ranging from 0.24 to 0.42 mg P g1 dry matter intake. The retention of P in growing chickens was not changed when 10-20 % of total P was provided by maize, barley or soybean.(AU)

Calcium particle size and feeding time influence egg shell quality in laying hens

An experiment with Leghorn laying hens was undertaken to determine the effect of oyster shell particle size and feeding time on different production variables, calcium retention, plasma calcium content and egg internal and external quality. Two hundred Leghorn layers (40 weeks old old) were allocated in five dietary treatments with four replicates during ten weeks. Two particle size combinations (wherein 50% of calcium substituted by medium or coarse particles (1-2 mm and 2-4 mm respectively) and two feeding time (8-pm or 9-am) were compared against a control diet (100% ground, 0.05). Hens fed diets containing coarse Ca had significantly greater feed intake and calcium content of excreta (p > 0.05), whereas medium particle size reduced feed intake compared to control. Coarse particle size and feeding time at 9-pm significantly increased the calcium content of egg shell, egg shell thickness, egg surface area (ESA) and shell weight per unit surface area (SWUSA) (p < 0.05). Plasma calcium concentration, gizzard digesta calcium content and egg specific gravity were not affected by treatments (p > 0.05). Providing of calcium at 9-pm resulted an increase of egg shell (%), shell weight and thickness (p < 0.05). The results have shown that substitution of fine oyster shell with 50% coarse particles (2-4 mm) and feeding time at 9-pm have better effects on egg shell quality.(AU)

Calcium particle size and feeding time influence egg shell quality in laying hens

An experiment with Leghorn laying hens was undertaken to determine the effect of oyster shell particle size and feeding time on different production variables, calcium retention, plasma calcium content and egg internal and external quality. Two hundred Leghorn layers (40 weeks old old) were allocated in five dietary treatments with four replicates during ten weeks. Two particle size combinations (wherein 50% of calcium substituted by medium or coarse particles (1-2 mm and 2-4 mm respectively) and two feeding time (8-pm or 9-am) were compared against a control diet (100% ground, 0.05). Hens fed diets containing coarse Ca had significantly greater feed intake and calcium content of excreta (p > 0.05), whereas medium particle size reduced feed intake compared to control. Coarse particle size and feeding time at 9-pm significantly increased the calcium content of egg shell, egg shell thickness, egg surface area (ESA) and shell weight per unit surface area (SWUSA) (p 0.05). Providing of calcium at 9-pm resulted an increase of egg shell (%), shell weight and thickness (p < 0.05). The results have shown that substitution of fine oyster shell with 50% coarse particles (2-4 mm) and feeding time at 9-pm have better effects on egg shell quality.

An external tag for fish: tagging effects in different fish size classes and its influence on growth performance and hematology of Lophiosilurus alexandri (Siluriformes: Pseudopimelodidae)

This study tested an external tag for juveniles of Lophiosilurus alexandri and measured the effects of tagging in different size classes of fishes. Experiment 1 evaluated the retention rate and influence of the tag on survival and growth of three hundred fishes divided Small, Medium and Large size classes. After 90 days of experiment the fishes had 100% survival and the tag had a higher retention rate for animals of the Large size class. Experiment 2 evaluated the tag's influence on hematology parameters of forty-two fishes at 5, 10 and 30 days post-tagging. In this experiment both tagged and untagged animals experienced 9.4% mortality. The hematocrit was higher on the 30th day for tagged animals than for untagged animals. No difference was observed for leukocytes, plasma protein, erythrocytes and mean corpuscular volume. It was concluded from Experiment 1 that the tag reduced growth performance when applied to small sized juvenile L. alexandri, and that the tag retention rate increased with increasing animal size. Among the hematological parameters studied for juveniles on the Experiment 2 the tag only influenced the hematocrit parameters, which shows that the tag can be used without considerable influence on the hematological parameters of juvenile L. alexandri.(AU)

Esse estudo testou a utilização de marcadores externos em juvenis de Lophiosilurus alexandri, assim como o tamanho mínimo ideal do peixe para marcação. No experimento 1 foi avaliado a taxa de retenção e a influência do marcador sobre a sobrevivência e crescimento dos peixes divididos por tamanho nas classes: Pequeno, Médio e Grande. Após 90 dias, os peixes apresentaram 100% de sobrevivência e uma taxa de retenção mais elevada para os animais classificados como grandes. O segundo experimento avaliou a influência do marcador sobre os parâmetros hematológicos dos animais após 5, 10 e 30 dias da marcação. Neste experimento, foram observados valores mais elevados para o hematócrito no 30º dia para os animais marcados, enquanto nenhuma diferença foi observada para leucócitos, proteína plasmática, eritrócitos e volume corpuscular médio. Concluiu-se o que o marcador reduziu a taxa de crescimento dos animais menores, e que a taxa de retenção aumentou com o aumento do tamanho do animal. Dos parâmetros hematológicos avaliados, o marcador influenciou apenas no valor do hematócrito, o que mostra que o marcador pode ser usado sem considerável influência nos parâmetros hematológicos do L. alexandri.(AU)

An external tag for fish: tagging effects in different fish size classes and its influence on growth performance and hematology of Lophiosilurus alexandri (Siluriformes: Pseudopimelodidae)

This study tested an external tag for juveniles of Lophiosilurus alexandri and measured the effects of tagging in different size classes of fishes. Experiment 1 evaluated the retention rate and influence of the tag on survival and growth of three hundred fishes divided Small, Medium and Large size classes. After 90 days of experiment the fishes had 100% survival and the tag had a higher retention rate for animals of the Large size class. Experiment 2 evaluated the tag's influence on hematology parameters of forty-two fishes at 5, 10 and 30 days post-tagging. In this experiment both tagged and untagged animals experienced 9.4% mortality. The hematocrit was higher on the 30th day for tagged animals than for untagged animals. No difference was observed for leukocytes, plasma protein, erythrocytes and mean corpuscular volume. It was concluded from Experiment 1 that the tag reduced growth performance when applied to small sized juvenile L. alexandri, and that the tag retention rate increased with increasing animal size. Among the hematological parameters studied for juveniles on the Experiment 2 the tag only influenced the hematocrit parameters, which shows that the tag can be used without considerable influence on the hematological parameters of juvenile L. alexandri.(AU)

Esse estudo testou a utilização de marcadores externos em juvenis de Lophiosilurus alexandri, assim como o tamanho mínimo ideal do peixe para marcação. No experimento 1 foi avaliado a taxa de retenção e a influência do marcador sobre a sobrevivência e crescimento dos peixes divididos por tamanho nas classes: Pequeno, Médio e Grande. Após 90 dias, os peixes apresentaram 100% de sobrevivência e uma taxa de retenção mais elevada para os animais classificados como grandes. O segundo experimento avaliou a influência do marcador sobre os parâmetros hematológicos dos animais após 5, 10 e 30 dias da marcação. Neste experimento, foram observados valores mais elevados para o hematócrito no 30º dia para os animais marcados, enquanto nenhuma diferença foi observada para leucócitos, proteína plasmática, eritrócitos e volume corpuscular médio. Concluiu-se o que o marcador reduziu a taxa de crescimento dos animais menores, e que a taxa de retenção aumentou com o aumento do tamanho do animal. Dos parâmetros hematológicos avaliados, o marcador influenciou apenas no valor do hematócrito, o que mostra que o marcador pode ser usado sem considerável influência nos parâmetros hematológicos do L. alexandri.(AU)

Effects of dietary zinc levels on the growth performance, organ zinc content, and zinc retention in broiler chickens

The objective of this study was to investigate the optimal zinc (Zn) requirement of broiler chickens based on Zn retention. On the day of hatch, 350 male Ross 308 broilers were randomly assigned to seven treatments with five replicates of ten birds each. Zinc was supplemented as ZnSO4·7H2O at 0, 20, 40, 60, 80, 100, or 120 mg/kg in the starter diet (fed from 1 to 21 d of age) and at 0, 16, 32, 48, 64, 80, or 96 mg/kg in the grower diet (fed from 22 to 42 d of age). The analyzed Zn levels were 34.98 and 27.57 mg/kg in the basal starter and grower diets, respectively. Supplemental Zn levels did not influence body weight gain, feed intake, feed conversion ratio, or liver Zn content of broilers at 21 and 42 d of age (p>0.05). Tibia ash Zn content of 21-d-old broilers increased when Zn supplementation level increased from 0 to 40 mg/kg Zn in (p<0.05). The highest breast muscle Zn content in 42-d-old broilers was observed when 100 and 80 mg Zn/kg was supplemented in the starter and grower diets, respectively. Fecal Zn content, Zn intake, Zn excretion, and Zn retention of 31- to 33-d-old broilers linearly increased with supplemental Zn levels (p<0.05). Zinc retention values, calculated as the difference between Zn intake and Zn excretion, were negative, about zero, and positive when starter/grower diets were supplemented with 0/0 and 20/16, 40/32, and 60/48 and 120/96 mg/kg, respectively. These results indicate that supplementing 40 and 32 mg Zn/kg in starter and grower diets, respectively, promote the growth performance of broiler chickens, while reduce Zn excretion in the environment.(AU)

Effects of dietary zinc levels on the growth performance, organ zinc content, and zinc retention in broiler chickens

The objective of this study was to investigate the optimal zinc (Zn) requirement of broiler chickens based on Zn retention. On the day of hatch, 350 male Ross 308 broilers were randomly assigned to seven treatments with five replicates of ten birds each. Zinc was supplemented as ZnSO4·7H2O at 0, 20, 40, 60, 80, 100, or 120 mg/kg in the starter diet (fed from 1 to 21 d of age) and at 0, 16, 32, 48, 64, 80, or 96 mg/kg in the grower diet (fed from 22 to 42 d of age). The analyzed Zn levels were 34.98 and 27.57 mg/kg in the basal starter and grower diets, respectively. Supplemental Zn levels did not influence body weight gain, feed intake, feed conversion ratio, or liver Zn content of broilers at 21 and 42 d of age (p>0.05). Tibia ash Zn content of 21-d-old broilers increased when Zn supplementation level increased from 0 to 40 mg/kg Zn in (p<0.05). The highest breast muscle Zn content in 42-d-old broilers was observed when 100 and 80 mg Zn/kg was supplemented in the starter and grower diets, respectively. Fecal Zn content, Zn intake, Zn excretion, and Zn retention of 31- to 33-d-old broilers linearly increased with supplemental Zn levels (p<0.05). Zinc retention values, calculated as the difference between Zn intake and Zn excretion, were negative, about zero, and positive when starter/grower diets were supplemented with 0/0 and 20/16, 40/32, and 60/48 and 120/96 mg/kg, respectively. These results indicate that supplementing 40 and 32 mg Zn/kg in starter and grower diets, respectively, promote the growth performance of broiler chickens, while reduce Zn excretion in the environment.