Variability in wheat: factors affecting its nutritional value

Wheat is a common raw material used to provide energy in broiler diets. Its apparent metabolisable energy and its influence on broiler performance varies between wheat samples. Reasons for that variability can be classified as intrinsic (variety, chemical composition) and extrinsic factors (growing conditions, storage, etc.), both of which affect nutrient digestibility and availability. However, these factors are not always considered when formulating the diets for broiler chickens. Moreover, research through the years has questioned the relation between wheat AME and animal performance. This review aims to describe factors that influence the observed variability in wheat nutritive value for broiler chickens by considering origin (variety, growing conditions and post-harvest storage), chemical composition of the grain (carbohydrates and protein) and the broiler chicken

Determination of faecal dry matter digestibility two weeks after weaning in twenty five day old weaned rabbits

[EN] The aim of this work was to analyse the evolution from 26 to 40 d of age of apparent faecal dry matter digestibility (DMd) in rabbits weaned at 25 d of age to define how to determine nutrient digestibility in the post-weaning period. Fifteen New Zealand ' Californian rabbits from five litters (3 rabbits/litter) weaned at 25 d of age and weighing 602±75g were fed ad libitum a commercial diet containing 20.0% crude protein and 33.5% NDF (on DM basis). Feed intake and faeces excretion were recorded daily from 25 to 40 d of age and DM digestibility determined. Litter affected DM intake and excretion (P = 0.013 and 0.014, respectively), and tended to affect DMd (P = 0.061), whereas age influenced all these traits (P < 0.001). Dry matter intake and DM excretion increased from 26 to 40 d of age by 158 and 480%, respectively. During the first week after weaning, DM intake increased more slowly than DM excretion (55 vs. 245%), but in the second week after weaning both increased by 67%. The correlation between daily feed intake was higher with the faeces excretion of the same day than with faeces excretion of the next day, and the first values were used to determine daily DMd. A broken line regression model was fitted to daily DMd, which decreased linearly from weaning to 32 d of age (2.17 ± 0.25 percentage units per day), whereas from 32 to 40 d it remained constant (69.4 ± 0.47%). Accordingly, for 25-d old weaned rabbits it would be advisable to begin a digestibility trial not before 32 d of age, using the first week after weaning as adaptation period. Average standard deviation of DMd decreased by 54% when the length of the collection period increased from 2 to 6 d. Consequently, the number of animals required to detect a significant difference among means depends on the length of the collection period. For a conventional collection period of four days, a difference of 2 percentage units could be detected by using 14 animals/treatment.Gómez-Conde, M.; García, J.; Villamide, M.; Carabaño, R. (2011). Determination of faecal dry matter digestibility two weeks after weaning in twenty five day old weaned rabbits. World Rabbit Science. 19(1):43-48. doi:10.4995/wrs.2011.816SWORD434819

ENERGY, PROTEIN AND FIBRE DIGESTIBILITY OF SOYA BEAN HULLS FOR RABBITS

[EN] Twenty New Zealand White x Califomian growing rabbits between 46 and 51 d of age were used to determine energy, protein and fibre digestibilities of soya bean hulls. The nutritive value was determined by the substitution method using a basal ~iet formulated for a high energy and protein content (11.4 MJ DE kg· and 19. 7% CP, respectively) to balance the low nutritive value of the soya bean hulls. This feedstuff was substituted at a 24% in the basal diet. Energy, protein and NDF digestibilities (%) of soya bean hulls calculated by difference were 34.5(±3.28), 30.0(±4.28) and 30.6(±4}0), respectively, and digestible energy value was 6.17(±0.60) MJ kg· DM. Standard errors of these estimations were similar respect to that obtained with other fibre by-products studied previously. The nutritive value of soya bean hulls was relatively low compared with other results from literature.[FR] Vingt lapins en croissance Néo-zélandais Blanc x Califomien agés de 46 8 51 jours ont été utilisés pour déterminer la digestibilité de /'énergie, des protéines et des fibras des cosses de soja. La valeur nutritionnelle a été déterminé par la méthode de substitution en utilisant un aliment témoin formulé pour contenir un taux élevé de protéines et d'énergie (11,4 Mj DE kg ·1 et19,7 % de protéines brutes, respectivement) pour compenser la faible valeur nutritionnelle des cosses de soja. Dans l'aliment expérimental, les cosses de soja ont remplacé 24 % de l'aliment témoin. La digestibilité de l'énergie, des protéines et des NDF (%) des cosses de soja, calculée par différence, est de : 34,5 (±3,28), 30,0 (±4,28) et 30,6 (±4,70) respectivement et la valeur de l'énergie digestible est de 6, 17 (±0,60) MJ kg·1 MS. L'erreur standard de ces estimations sont semblables 8 ce/les obtenues pour d'autres sous produits préalablement étudiés. Cette valeur nutritive des cosses de soja est relativement faible par rapport 8 ce/le que /'on peut trouver dans la littérature.This work has been supported by CICYT (AGF93-0870) and CDTI-Eureka Program (EU-619)Garcia, J.; Villamide, M.; De Blas, J. (1997). ENERGY, PROTEIN AND FIBRE DIGESTIBILITY OF SOYA BEAN HULLS FOR RABBITS. World Rabbit Science. 05(3):111-113. doi:10.4995/wrs.1997.328SWORD11111305

ENERGY, PROTEIN AND FIBRE DIGESTIBILITY OF PAPRIKA MEAL FOR RABBITS

[EN] Twenty New Zealand White x Californian growing rabbits between 46 and 51 d of age were used to determine energy, protein and fibra digestibilities of paprika meal. The nutritiva value was determinad by the substitution method ~sing a basal diet formulated for a high energy content (11.4 MJ DE kg- ) to balance the low nutritiva value of the paprika meal. This feedstuff was substituted at a 24.4% in the basal diet. Energy, protein and NDF digestibilities (%) of paprika meal calculated by difference were 38.2(±2.55), 63.1 (±4.42) and 30. 7(±6.Q?). respectively, and its digestible energy value was 7.34(±0.49) MJ kg- DM. Standard errors of these estimations were similar respect to those obtained with other fibrous by-products studied previously[FR] Afin de déterminer la digestibilité de l'énergie, des protéines et des fibras de la farine de paprika, on a utilisé 20 lapins croisés NZW x CAL en croissance, agés de 46 a 51 jours. La valeur nutritiva a été déterminée par la méthode de substituti~n en utilisant un aliment de base riche en énergie (11,4 MJ ED kg- ) pour compensar la faible valeur nutritiva de la farine de paprika. 24,4% du régime de base ont été remplacés par le paprika. La digestibilité de l'énergie, des protéines et des fibras de la farine de paprika, calculées par différence, ont été de 38,2 ± 2,55 ; 63, 1 ± 4,42 et 30,7 ± 6,06 resf1i9ctivement, pour un taux d'énergie digestible de 7,34 :t 0,49 MJ kg- MS. Les valeurs de l'erreur standard liées a ces estimations sont analogues a cellas trouvées antérieurement pour d'autre sousproduits fibreux.This work has been supported by CICYT (AGF93-0870) and CDTI-Eureka Program (EU-619)Garcia, J.; Villamide, M.; Blas, JD. (1997). ENERGY, PROTEIN AND FIBRE DIGESTIBILITY OF PAPRIKA MEAL FOR RABBITS. World Rabbit Science. 05(4):139-141. doi:10.4995/wrs.1997.333SWORD13914105

ENERGY, PROTEIN AND FIBRE DIGESTIBILITY OF SUNFLOWER HULLS, OLIVE LEAVES AND NaOH-TREATED BARLEY STRAW FOR RABBITS

[EN] One hundred and sixty nine New Zealand White x Californian rabbits were used to determine the nutritive value of sunflower hulls, olive leaves and NaOH-treated barley straw. These feedstuffs were substituted at 6, 12, 18 and 24% in a basal diet formulated for a high energy and protein content. Digestible energy (DE) values calculated by difference for the highest substitution le~els (18 and 24%) were 4.77(±0.32), 6.16(±0.37) and 4.10(±0.32) MJ kg· DM for sunflower hulls, olive leaves and NaOH-treated barley straw, respectively. Standard errors of these estimations decreased with level of substitution (by 83% on average from 6 to 24% of inclusion leve!). Crude protein digestibility values obtained were not consistent due to its high standard errors (±48 as average). The values estimated for neutral detergent fibre digestibility (%) were relatively low and had also high standard errors: 10.7(±5.70); 7.76(±7.89) and 5.76(±6.14) for sunflower hulls, olive leaves and NaOH-treated barley straw, respectively. An stepwise regression equation to predict DE value of fibrous feeds was developed from data of this work and from literature using as independent variables ash, CP, crude fibre (CF), ether e'1'1ract (%DM) and gross energy. The equ~ion obtained was: DE(MJ kg· DM)= 14.46 (±1.10) - 0.23(±0.032) CF (R =O. 781; RSD=1.43; P<0.001 ).[FR] Cent soixante neuf lapins NZW x Californien ont été utilisés pour déterminer la valeur nutritives des coques de tournesol, des feuilles d'olivier et de la paille d'orge traitée a la soude. Ces aliments ont été substitués aux taux de 6, 12, 18 et 24% aux éléments d'un régime de base au contenu élévé d'énergie et de protéines. Les valeurs d'Energie Digestible calculées par différence pour les niveaux de substitution les plus élevés~18 et 24%) sont de 4,77 ± 0,32 - 6,16 ± 0,37 et 4, 1 O ± 0,32 Mj/kg· MS pour les coques de tournesol, les feuilles d'olivier et la paille d'orge traitée a la soude respectivement. L'erreur standard lieé a ces estimations décroit avec le niveau de substitution (de 83% en moyenne pour les niveaux d'inclusion de 6 a 24%). Les valeurs de digestibilité des protéines brutes obtenues ne sont pas fiables a cause de cette forte erreur standard (±48 en moyenne). Les valeurs estimées de la digestibilité des NDF (%) sont relativement basses et sont aussi assorties de fortes erreurs standards (10,7 ± 5,70 - 7,76 ± 7,89 et 5,76 ± 6,14) pour les coques de tournesol, les feuilles d'olivier et la paille d'orge traitée, respectivement. Une équation de prédiction de la teneur en Energie Digestible des aliments fibreux a été déterminée par régression multiple et progressive a partir des résultats de ce travail et des données de la littérature. Elle utilise comme variables indépendantes les cendres, les protéine brutes, les fibres brutes, l'extrait éthéré (% MS) et l'énergie brute. L'équation obtenue est !ª suivante : DE(MJ kg· DM)= 14,46 (±1,10) - 0,23(±0,032) CF (R =0,781; RSD=1,43; P<0,001),This work has been supported by CICYT (AGF93-0870) and CDTI-Eureka Program (EU-619)Garcia, J.; Villamide, M.; De Blas, J. (1996). ENERGY, PROTEIN AND FIBRE DIGESTIBILITY OF SUNFLOWER HULLS, OLIVE LEAVES AND NaOH-TREATED BARLEY STRAW FOR RABBITS. World Rabbit Science. 04(4). doi:10.4995/wrs.1996.296SWORD04

Novas tabelas de valor nutritivo para coelhos

International audienc