Research Note: Influence of monocalcium phosphate and phytase in the diet on phytate degradation in cecectomized laying hens.

This study investigated the effects of phytase and monocalcium phosphate supplementation on the dephosphorylation of phytic acid [myo-inositol 1,2,3,4,5,6-hexakis (dihydrogen phosphate); InsP6] in cecectomized laying hens using total excreta collection. Four corn-soybean meal-rapeseed meal-based diets were mixed with or without 6 g of monocalcium phosphate/kg, with or without supplementation of 1,500 FTU phytase/kg, and had the same calcium concentration at 39 g/kg of feed. Each diet was tested in 5 replicates using a row-column design with 10 cecectomized laying hens in 2 periods. The hens received 120 g/d of feed while being housed individually in metabolism units, and total excreta were collected for a period of 4 d. The monocalcium phosphate × phytase interaction was not significant for InsP6 degradation (P = 0.054). Phytase increased InsP6 disappearance from 13% to 83% (P < 0.001), whereas monocalcium phosphate had no effect. Concentrations of most of the lower inositol phosphate isomers in excreta were higher when monocalcium phosphate was added to the diets. The concentration of Ins(1,2,5,6)P4 in excreta was the highest among the studied partially dephosphorylated inositol phosphates with phytase supplementation and was higher than in diets without phytase supplementation (P < 0.001). Supplementation with phytase increased myo-inositol concentration in excreta (P = 0.002), whereas monocalcium phosphate had no effect. Phosphorus utilization ranged from 4% to 18% and was not significantly affected by the treatments. These results suggest that phytase supplementation markedly increased InsP6 degradation in laying hens. The cecectomized laying hen assay may be suitable for studying the effects of phytase supplementation on phytate dephosphorylation under dietary conditions when performance and phosphorus excretion are unlikely to be affected.

Use of the precision-fed cecectomized rooster assay to determine standardized amino acid digestibility, true metabolizable energy content, and digestible indispensable amino acid scores of plant-based protein by-products used in canine and feline diets.

Traditionally, protein by-products from oil seeds and cereal grains have been used in pet foods as sustainable, inexpensive, and protein-rich ingredients. However, the on-going demonization of soy- and corn-based ingredients continue to hinder their use in pet food and treat formulations. Ideally, the further demonstration of their protein quality and nutrient composition may encourage their favorable return as acceptable ingredients in pet foods and treats. Therefore, the objectives of this study were to determine the macronutrient composition, indispensable amino acid profile, standardized amino acid digestibility, true metabolizable energy content corrected for nitrogen (TMEn), and digestible indispensable amino acid scores (DIAAS-like) of soy flakes (SF), peanut flour (PF), soybean meal (SBM), and corn gluten meal (CGM). Standardized amino acid digestibility was assessed using the precision-fed cecectomized rooster assay. All test ingredients demonstrated a profile of highly digestible indispensable amino acids except for lysine in PF, which was lowest (P < 0.05) at 45.5%. The SBM and CGM had the highest (P > 0.05) digestibilities of indispensable amino acids. A DIAAS-like value was calculated for each ingredient using either AAFCO (2020) recommended values or NRC (2006) recommended allowances as the reference protein pattern. For adult dogs compared to AAFCO recommended values, the first-limiting amino acid was lysine for PF and CGM but it was methionine for SF and SBM. For adult cats compared to AAFCO recommended values, the first-limiting amino acid was lysine for PF and CGM but it was threonine for SF. There was no first-limiting amino acid in SBM for cats as DIAAS-like values were over 100% for all indispensable amino acids. The TMEn values were highest (P < 0.05) for PF and CGM (4.58 and 4.31 kcal/g [dry matter basis], respectively). The protein quality of these plant-based protein by-products reflects their value as nutritional ingredients for canine and feline diets. However, the prior processing of these by-products must be considered before exposing them to additional processing methods, such as extrusion. Additionally, the inclusion of complementary proteins or supplemental amino acids will be needed to meet all indispensable amino acid requirements for a portion of nutritionally complete and balanced pet food.

Effect of low-temperature drying on the nitrogenous compounds and inositol phosphates in broiler chickens and cecectomized laying hen excreta.

We investigated how the chemical composition of broiler chicken and cecectomized laying hen excreta is affected by drying in a forced-air drying chamber at low temperatures. Excreta that was immediately frozen after voiding provided the reference values. The excreta were dried in drying chambers for 4 hr, 6 hr, and 12 hr at 23°C or 33°C in the broiler experiment and 19°C or 29°C in the cecectomized laying hen experiment. The total N and inositol phosphate concentrations in the excreta of broiler chickens and cecectomized laying hens were not influenced (p > .050), except for one inositol tetrakisphosphate isomer (p = .026) in broilers. Compared to fresh excreta, drying did not affect the ammonia concentrations in the cecectomized laying hen experiment (p > .050), but the ammonia concentration was lower when dried for 12 hr at 33°C in the broiler experiment (p = .002). Amino acid concentrations in cecectomized laying hen excreta decreased until 4 hr of drying and then increased at both drying temperatures (p < .001). The results indicate that the applicability of drying poultry excreta at low temperatures in forced-air drying chambers to determine the chemical compound concentrations is trait-dependent. Future studies are necessary to investigate whether these results are also dependent upon the amount of excreta stored in the drying chambers.

Use of precision-fed cecectomized rooster assay and digestible indispensable amino acid scores to characterize plant- and yeast-concentrated proteins for inclusion in canine and feline diets.

Increased consumer interest in high-quality and novel protein sources has driven the demand for the inclusion of protein-rich ingredients in companion animal diets. Novel protein concentrates, with protein contents of at least 50%, have been used to satisfy these consumer demands. However, minimal information is available regarding the macronutrient composition and protein quality of these ingredients that is needed for proper formulation of pet foods. Therefore, the objectives of this study were to determine the macronutrient and amino acid compositions, standardized amino acid digestibility according to the precision-fed rooster assay, and protein quality using digestible indispensable amino acid score (DIAAS like) of pea protein (PP), potato protein (POP), faba bean protein (FBP), soy protein concentrate (SPC), and dried yeast (DY). Precision-fed rooster assays were conducted using cecectomized roosters to calculate standardized amino acid digestibility and true metabolizable energy corrected for nitrogen (TMEn). For all five protein concentrates, all essential amino acids were highly digestible (88.0% to 96.3%, dry matter basis) with differences (P < 0.05) in only lysine, methionine, and tryptophan digestibilities. The TMEn values were highest for POP (4.22 kcal/g) and DY (3.61 kcal/g). The DIAAS-like values for adult dogs indicated that methionine was the first-limiting amino acid in all protein concentrates except POP, where the first-limiting amino acid was tryptophan. Using Association of American Feed Control Officials (AAFCO)-recommended values for adult cats, DIAAS-like values for methionine were lowest (P < 0.05) for FBP at 81.5%, with all other amino acids for all protein concentrates over 100%. The National Research Council (NRC)-recommended allowances for adult cats indicated that DIAAS-like methionine values for PP (92.7%) and FBP (73.8%) were significantly lower (P < 0.05) with these being the first-limiting amino acids, with the remaining amino acids above 100% for the other protein concentrates. The protein quality and high essential amino acid digestibility of these protein concentrates indicate that they would be viable protein sources in canine and feline diets. However, additional complementary protein sources should be included to meet the requirements of all essential amino acids.

Macronutrient composition, true metabolizable energy and amino acid digestibility, and indispensable amino acid scoring of pulse ingredients for use in canine and feline diets.

The rising consumer demand for alternative and sustainable protein sources drives the popularity of the use of plant-based proteins in the pet food industry. Pulse crops, which include beans, peas, lentils, and chickpeas, have become an important addition to both human and animal diets due to their protein content and functional properties. However, knowledge of their nutrient composition and protein quality is necessary for the proper formulation of these ingredients in pet foods. The objective of this study was to determine the macronutrient composition and standardized amino acid digestibility and to describe the protein quality through the use of digestible indispensable amino acid scores (DIAAS-like) of five pulse ingredients. Black bean (BB) grits, garbanzo beans (GB), green lentils (GL), navy bean (NB) powder, and yellow peas (YP) were analyzed for dry matter (DM), ash and organic matter (OM), crude protein (CP), gross energy (GE), acid hydrolyzed fat (AHF), and total dietary fiber (TDF) to determine the macronutrient composition. Precision-fed rooster assays were conducted using cecectomized roosters to calculate standardized amino acid digestibility and true metabolizable energy corrected for nitrogen (TMEn). The essential amino acids, with the exception of methionine, were highly digestible with digestibility values of 80% to 90% (dry matter basis) for all selected pulse ingredients. BB grits had the lowest (P < 0.05) digestibility of arginine (86.5%) and histidine (80.6%) in contrast to GB (94.9% and 89.9%, respectively). The TMEn of GB was highest (P < 0.05) at 3.56 kcal/g compared with the other pulses. The DIAAS-like values for adult dogs were consistently the lowest for methionine for all pulses, making it the first-limiting amino acid in these ingredients. The DIAAS-like values for adult cats showed GL had lowest (P < 0.05) score in tryptophan compared with other pulses when using both AAFCO values and NRC recommended allowances as reference proteins. Methionine was the first-limiting amino acid for YP and tryptophan for GL. Based on macronutrient composition, protein quality, and amino acid digestibility, it can be concluded that pulse ingredients have the required nutritional characteristics to be viable protein sources in canine and feline foods. However, the use of complementary protein sources is recommended to counterbalance any potential limiting amino acids in pulse ingredients.

La diarrea inducida con lactosa es mas severa, prolongada y produce mayores pérdidas fecales de macronutrientes en ratas cecotomizadas que en ratas intactas / Lactose-induced diarrhea is more severe, last longer and produces more fecal macronutrient losses in cecectomized than in intact rats

La diarrea inducida con lactosa en ratas ha servido para estudiar la alimentación durante la diarrea. Sin embargo, las ratas se adaptan al consumo de lactosa por lo que la diarrea dura aproximadamente una semana. Para establecer si la remoción del ciego podría prolongarla, aquí se comparó esta diarrea en ratas intactas y cecotomizadas. El experimento incluyó 16 ratas intactas y 16 cecotomizadas. A la mitad de las ratas en cada grupo se les ofreció una dieta con 45% de lactosa (grupo diarrea) y a la otra mitad una dieta sin lactosa (grupo control). El experimento duró 21 días con 3 recolecciones de heces de 48 h (días 2-4, 9-11 y 17-19). Los resultados mostraron que durante la primera recolección hubo diarreas similares tanto en los grupos de ratas intactas como cecotomizadas, pero en las próximas, sólo las cecotomizadas tenían una diarrea cuya severidad aumentó (3,5 veces) con el tiempo. Adicionalmente, en los dos tipos de ratas, las pérdidas fecales de proteína y grasa fueron proporcionales a la masa fecal húmeda excretada, pero fueron 2 veces más altas en las cecotomizadas. Se concluye que la cecotomía previene la adaptación, aumenta la severidad y prolonga la diarrea inducida con lactosa e incrementa notablemente las pérdidas fecales de los macronutrientes y reduce la eficiencia del alimento(AU)

Lactose induced diarrhea in rats has been used for studying the appropriated feeding during diarrhea. However, rats adapt to lactose and this diarrhea last approximately one week. In order to establish if cecum removal could prolong it, here lactose induced diarrhea was produced in intact and cecectomized rats. In the experiment there were 16 intact and 16 cecectomized rats. Halve of the rats in each group were fed a diet with 45% lactose (Diarrhea group) and the other halve a lactose free diet (Control group). The experiment lasted 21 days and included three 48h fecal collections (days 2-4, 9-11 and 17-19). The results showed that during the first collection both groups had diarrheas of similar severity but thereafter, only the cecectomized had a diarrhea whose severity increased (3.5 times) with time. Additionally, in both groups of rats, protein and fat fecal losses were proportional to fecal output but they were higher (2 times) in the cecectomized group. In conclusion, cecectomy prevents lactose adaptation and results in a diarrhea that last longer and it is more severe (3.5 times). Also in these rats fecal losses of macronutrients are higher whereas feed efficiency is lower(AU)

Composição química, valores de energia metabolizável e aminoácidos digestíveis de subprodutos do arroz para frangos de corte / Chemical composition, metabolizable energy and digestible amino acids values of rice by-products for broilers

Dois experimentos foram conduzidos para determinar a composição química, os valores de energia e os coeficientes de digestibilidade dos aminoácidos, do farelo de arroz integral (FAI) e da quirera de arroz (QA). No primeiro estudo, foram utilizadas 144 aves, com 21 dias de idade, machos, linhagem Cobb, que tiveram suas excretas totalmente coletadas para determinação da energia metabolizável aparente (EMA) e energia metabolizável aparente corrigida (EMAn). O delineamento experimental foi inteiramente casualizado, com três tratamentos e seis repetições, com oito aves cada. No segundo experimento, foi utilizado o método de alimentação forçada para a determinação dos coeficientes de digestibilidade dos aminoácidos. O delineamento foi inteiramente casualizado, com dois alimentos e um jejum e seis repetições com um galo cada. Os valores de MS, PB, EE, FB, EMA e EMAn foram, respectivamente, para FAI: 88,6 por cento; 11,8 por cento; 15,3 por cento; 10,2 por cento; 2968kcal kg-1 e 2804kcal kg-1 e para QA: 93,5 por cento; 9,1 por cento; 0,73 por cento; 0,45 por cento; 3338kcal kg-1 e 3239kcal kg-1. Os valores médios encontrados dos coeficientes de digestibilidade de aminoácidos essenciais e não essenciais foram, respectivamente, de 75,9 por cento e 73,9 por cento, para FAI, e 77,9 por cento e 76,5 por cento, para QA. Embora tenham apresentado níveis inferiores de energia, FAI e a QA podem ser utilizados nas rações de aves em substituição ao milho, uma vez que tiveram níveis maiores de proteína bruta e aminoácidos digestíveis.

Two experiments were conducted to determine the chemical composition, energy and the digestibility coefficients of the amino acids of the whole rice meal (WRM) and broken rice (BR). In the first trial, one hundred forty four broilers, 21 days of age, male, of Cobb strain had their excreta totally collected in order to determine the apparent metabolizable energy (AME) and corrected apparent metabolizable energy (AMEn). The experimental design was completely randomized, with three treatments and six replicates with eight birds each one. In the second trial, it was used the forced feeding method with cecectomized cockerels to determine the digestibility coefficients of the amino acids. The design was entirely randomized, with two feeds and one fasting and six replicates with one bird each one. The values of DM, CP, EE, CF, AME and AMEn were, respectively, to WRM: 88.6 percent; 11.8 percent; 15.3 percent; 10.2 percent; 2968kcal kg-1 and 2804kcal kg-1 and to BR: 93.5 percent; 9.1 percent; 0.73 percent; 0.45 percent; 3338kcal kg-1 and 3239kcal kg-1. The average values of digestibility coefficients of essential and non-essential amino acids were, respectively, 75.9 percent and 73.9 percent to WRM and 77.9 percent and 76.5 percent to BR. The WRM and the BR can be used in the diets of broilers in substitution to the corn, however showed lower metabolizable energy levels, had higher levels of crude protein and digestible amino acid.