ABSTRACT
This experiment aimed at evaluating the effects of including the enzyme, ß-mannanase, in dog (Canis lupus familiaris) diets based on either poultry (Gallus gallus domesticus) by-product meal (PBM) or soybean [Glycine max (L.) Merr.] Meal (SBM). The second objective was to evaluate 3 methods for determining energy and nutrient digestibility values in diets fed to dogs: total fecal collection (TFC) and use of aia or crude fiber (CF) as a marker. Eight dogs were allotted to a replicated latin square (4 by 4) design. There were 2 diets based on PBM as the major protein source and 2 diets based on SBM as the major protein source. Within each protein source, 1 diet contained no ß-mannanase and 1 diet contained 0.01% ß-mannanase. Diets were fed for an adaptation period of 5 d followed by 5 d of TFC. Fecal score (1 = watery feces to 5 = dry, hard pellets), pH, DM, and fecal volume were determined. The apparent total tract digestibility (ATTD) of DM, OM, CP, ether extract (EE), N-free extract (NFE), and GE, and ME content were calculated using the methods of TFC, AIA, and CF. Data were analyzed as a 2 by 2 by 3 split-split-plot design (ß-mannanase, protein source, and digestibility calculation procedure). There were interactions between protein source and ß-mannanase (P < 0.05). Supplementation of ß-mannanase increased ATTD of nutrients and energy and ME (+ 195.3 kcal/kg) and also reduced fecal production in the diet with SBM, but not in the diet that contained PBM. There was an interaction between digestibility calculation procedure and protein source (P < 0.05). The use of AIA overestimated ATTD of the diets containing PBM, but digestibility values estimated based on TFC and CF were not different. Dogs fed diets containing SBM produced more feces with greater moisture content and lower pH compared with dogs fed the PBM diet (P < 0.05). Addition of 0.01% ß-mannanase increased (P < 0.05) the digestibility and ME content of the diets containing SBM, but did not improve (P > 0.05) fecal texture. Results indicated that values for ATTD of energy and nutrients in diets containing sbm are not different if they are calculated based on TFC, AIA, or CF, but use of AIA may result in an overestimation of values for ATTD of energy and nutrients in diets containing PBM.
Subject(s)
Animal Feed/analysis , Diet/veterinary , Dietary Proteins/analysis , Digestion/drug effects , beta-Mannosidase/pharmacology , Animal Nutritional Physiological Phenomena , Animals , Dietary Proteins/metabolism , Digestion/physiology , Dogs , Feces/chemistry , Female , Male , Meat/analysis , Poultry , Glycine max/chemistryABSTRACT
Investigou-se o efeito da suplementaçäo de glutamina na dieta sobre o consumo de raçäo, ganho de peso e conversäo alimentar e sobre a estrutura da mucosa intestinal de frangos. Foram utilizados 320 pintos de corte machos distribuídos em um delineamento inteiramente ao acaso com dois tratamentos e quatro repetiçöes, sendo T1 suplementado com 1 por cento de L-glutamina na dieta e T2 controle. Os índices de desempenho foram analisados aos 7, 21 e 49 dias de idade das aves. Aos 7 e 14 dias de idade oito aves foram sacrificadas para colheita de fragmentos de cada porçäo do intestino delgado para avaliaçäo da morfometria intestinal em microscopia de luz em sistema analisador de imagens "Video Plan". As variáveis estudadas foram altura dos vilos, profundidade de cripta e relaçäo vilo: cripta. A adiçäo de 1 por cento de glutamina à dieta de frangos näo influenciou (P>0,05) o seu desempenho zootécnico. Entretanto, 1 por cento de glutamina na raçäo foi capaz de alterar (P<0,01) a altura do vilo, a profundidade de cripta e a relaçäo vilo:cripta no duodeno, bem como a altura de vilo do íleo de frangos no sétimo dia de idade
