RESUMO

This study aimed to evaluate the effects of calcium salts of fatty acids (CSFA) from soybean oil in diets with different levels of rumen degradable protein (RDP) on bio-hydrogenation extent, and fatty acid (FA) profile intake, omasal digesta, rumen bacteria, and milk fat. Eight Holstein lactating cows were used in a replicated 4 × 4 Latin square design. Treatments were arranged in a 2 × 2 factorial design with two CSFA levels (0 or 33.2 g/kg DM of CSFA) and two RDP levels (98.0 or 110 g/kg DM). There was RDP and CSFA interaction effect on the omasal flow of total FA and some specific FA. Only in -CSFA diets, the higher RDP level increased omasal flow of total FA. Dietary RDP levels did not affect the FA profile of bacteria and milk fat. Feeding CSFA reduced or tended to reduce the bacterial proportion of C15:0, C16:0, C16:1, C17:0, and C18:0 FA and decreased the concentrations of short- and medium-chain FA (<18C) and increased the concentrations of unsaturated and long-chain FA (≥18C) in milk fat. Feeding CSFA of soybean oil increases the intake and omasal flow of FA and augments unsaturated FA content in bacteria pellets and milk fat.

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RESUMO

The objective of this study was to determine the effects of growing stage (GS) on morphological and chemical composition of whole-plant soybean (WPS), and fermentative profile and chemical composition of whole-plant soybean silage (SS). This study was divided into two trials conducted in a complete randomised block design. The first trial evaluated the effect of GS from R1 to R8 (59-135 d after sowing) on morphological and chemical composition of WPS and its botanical components. The second trial determined the effects of GS from R3 (71 d after sowing) to R7 (124 d after sowing) on dry matter (DM) losses, fermentative profile, chemical composition and aerobic stability of SS. The proportion of leaves in WPS was reduced, while stem and pod proportions were increased as the GS progressed. Ensiling WPS at R6 and R7 decreased the contents of acetic acid, lactic acid and branched-chain fatty acids, and ethanol, and increased the contents of propionic acid and NH3-N. However, silage butyric acid concentrations in R6 and R7 were relatively high (18.1 and 19.9 g/kg DM, respectively). Butyric acid and buffering capacity varied according to GS with the lowest values observed in silages derived from GS R3, R5 and R7, and the highest values observed in silages made from GS R5. Later GS resulted in greater contents of DM, crude protein and ether extract, and lower contents of acid detergent fibre and non-fibre carbohydrate in SS. The high fat of SS produced from later GS limits high inclusion levels in ruminant diets. Morphological components impacted chemical composition of SS, whereas the R7 stage improved fermentative profile and resulted in an SS with greater in situ degradability of DM and neutral detergent fibre.

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RESUMO

Citrus pulp can replace corn in feedlot diets in order to decrease metabolic problems by reducing formation of lactate ruminal. However, while eating, animals can easily select against pelleted citrus pulp due to the greater particle size of the pellet. Therefore, grinding citrus pulp pellet can be an alternative to decrease particle selectivity. This study was realized to evaluate the replacement of ground corn by pelleted citrus pulp and ground citrus pulp on animal performance, sorting index, and feeding behavior of Nellore heifers. Thirty-six Nellore heifers were randomly assigned to three treatments: control diet based on ground corn (GC), partial replacement of GC by ground citrus pulp (GCP), and partial replacement of GC by pelleted citrus pulp (PCP). . Heifers fed with the GC diet had higher final body weight (BW), average daily gain (ADG), and dry matter intake (DMI) compared with heifers fed with citrus pulp (P < 0.05). Ground citrus pulp increased DMI and fiber intake compared with the PCP group (P < 0.05). Heifers fed with PCP and GCP sorted for diet particles from 8 to 19 mm and selected particles with less than 1.18 mm (P < 0.05). Thus, the ground citrus pulp is better than pelleted citrus pulp due to higher feed intake and ADG, in consequence of lower selection index.(AU)

A polpa cítrica pode substituir o milho nas dietas em confinamento, a fim de diminuir os problemas metabólicos, reduzindo a formação de lactato. No entanto, enquanto comem, os animais podem selecionar facilmente a polpa cítrica peletizada, devido ao maior tamanho de partícula do pélete. Portanto, a moagem do pélete da polpa cítrica pode ser uma alternativa para diminuir a seletividade de partículas. Este estudo teve como objetivo avaliar a substituição do milho moído por polpa cítrica peletizada e polpa cítrica moída sobre o desempenho animal, índice de seleção de partículas e comportamento alimentar de novilhas Nelore. Trinta e seis novilhas Nelore foram distribuídas aleatoriamente em três tratamentos: dieta controle à base de milho moído (MM), substituição parcial de MM por polpa cítrica moída (PCM) e substituição parcial de MM por polpa cítrica granulada (PCP). Novilhas alimentadas com dieta contendo MM apresentaram maior peso corporal final (PC), ganho médio diário (GMD) e consumo de matéria seca (CMS) em comparação com novilhas alimentadas com polpa cítrica (P <0,05). A polpa cítrica moída aumentou o CMS e o consumo de fibra em comparação ao grupo PCP (P <0,05). Novilhas alimentadas com PCP e PCM selecionaram a favor de partículas da dieta entre 8 e 19 mm e selecionaram partículas com menos de 1,18 mm (P <0,05). Assim, a polpa cítrica moída é melhor que a polpa cítrica peletizada, devido ao maior consumo de ração e ganho médio diário, em consequência do menor índice de seleção de partículas.(AU)

Assuntos

RESUMO

Citrus pulp can replace corn in feedlot diets in order to decrease metabolic problems by reducing formation of lactate ruminal. However, while eating, animals can easily select against pelleted citrus pulp due to the greater particle size of the pellet. Therefore, grinding citrus pulp pellet can be an alternative to decrease particle selectivity. This study was realized to evaluate the replacement of ground corn by pelleted citrus pulp and ground citrus pulp on animal performance, sorting index, and feeding behavior of Nellore heifers. Thirty-six Nellore heifers were randomly assigned to three treatments: control diet based on ground corn (GC), partial replacement of GC by ground citrus pulp (GCP), and partial replacement of GC by pelleted citrus pulp (PCP). . Heifers fed with the GC diet had higher final body weight (BW), average daily gain (ADG), and dry matter intake (DMI) compared with heifers fed with citrus pulp (P < 0.05). Ground citrus pulp increased DMI and fiber intake compared with the PCP group (P < 0.05). Heifers fed with PCP and GCP sorted for diet particles from 8 to 19 mm and selected particles with less than 1.18 mm (P < 0.05). Thus, the ground citrus pulp is better than pelleted citrus pulp due to higher feed intake and ADG, in consequence of lower selection index.

A polpa cítrica pode substituir o milho nas dietas em confinamento, a fim de diminuir os problemas metabólicos, reduzindo a formação de lactato. No entanto, enquanto comem, os animais podem selecionar facilmente a polpa cítrica peletizada, devido ao maior tamanho de partícula do pélete. Portanto, a moagem do pélete da polpa cítrica pode ser uma alternativa para diminuir a seletividade de partículas. Este estudo teve como objetivo avaliar a substituição do milho moído por polpa cítrica peletizada e polpa cítrica moída sobre o desempenho animal, índice de seleção de partículas e comportamento alimentar de novilhas Nelore. Trinta e seis novilhas Nelore foram distribuídas aleatoriamente em três tratamentos: dieta controle à base de milho moído (MM), substituição parcial de MM por polpa cítrica moída (PCM) e substituição parcial de MM por polpa cítrica granulada (PCP). Novilhas alimentadas com dieta contendo MM apresentaram maior peso corporal final (PC), ganho médio diário (GMD) e consumo de matéria seca (CMS) em comparação com novilhas alimentadas com polpa cítrica (P <0,05). A polpa cítrica moída aumentou o CMS e o consumo de fibra em comparação ao grupo PCP (P <0,05). Novilhas alimentadas com PCP e PCM selecionaram a favor de partículas da dieta entre 8 e 19 mm e selecionaram partículas com menos de 1,18 mm (P <0,05). Assim, a polpa cítrica moída é melhor que a polpa cítrica peletizada, devido ao maior consumo de ração e ganho médio diário, em consequência do menor índice de seleção de partículas.

Assuntos