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This study aimed to assess the feasibility of visible/near-infrared reflectance (Vis-NIR) and near-infrared transmittance (NIT) spectroscopy to predict total and gelatinized starch and fiber fractions in extruded dry dog food. Reference laboratory analyses were performed on 81 samples, and the spectrum of each ground sample was obtained through Vis-NIR and NIT spectrometers. Prediction equations for each instrument were developed by modified partial least squares regressions and validated by cross- (CrV) and external validation (ExV) procedures. All studied traits were better predicted by Vis-NIR than NIT spectroscopy. With Vis-NIR, excellent prediction models were obtained for total starch (residual predictive deviation, RPDCrV = 6.33, RPDExV = 4.43), gelatinized starch (RPDCrV = 4.62, RPDExV = 4.36), neutral detergent fiber (NDF, RPDCrV = 3.93, RPDExV = 4.31), and acid detergent fiber (ADF, RPDCrV = 5.80, RPDExV = 5.67). With NIT, RPDCrV ranged from 1.75 (ADF) to 2.61 (acid detergent lignin, ADL) and RPDExV from 1.71 (ADL) to 2.16 (total starch). In conclusion, results of the present study demonstrated the feasibility of at-line Vis-NIR spectroscopy in predicting total and gelatinized starch, NDF, and ADF, with lower accuracy for ADL, whereas results do not support the applicability of NIT spectroscopy to predict those traits.

Quinoa (Chenopodium quinoa Willd.) is native to the Andean region and belongs to the group of crops known as pseudocereals. It has great potential for improving food for humans and animals due to its interesting nutritional value. Quinoa was studied to determine the fatty acid (FA) composition, chemical composition, gross energy, in vitro dry matter (DM) digestibility (IVDMD) and neutral detergent fibre digestibility (IVNDFD) of the seeds and plant during growth. Herbage samples were collected six times at progressive morphological stages from the early vegetative to the grain fill stage. Effects of plant ageing was analysed by polynomial contrasts. The chemical composition of quinoa is closely connected to development of the plant with the quality of crop decreased with increasing morphological stages. Dry matter, organic matter (OM), and neutral detergent fibre (NDFom) content increased linearly from the mid vegetative to the grain fill stage, while acid detergent fibre (ADFom) content increased linearly from the first to the last stage. The pattern of FA in the seed was characterised by: palmitic acid (PA, C16:0), oleic acid (OA, C18:1 n-9) and linoleic acid (LA, C18:2 n-6). Among main FA of the plant during growth, α-linolenic acid (ALA, C18:3 n-3) was the most abundant FA (from 385 to 473 g/kg of total FA), while LA content, which ranged from 146 to 176 g/kg of total FA, decreased with increasing growth until the shoot stage and then increased, while PA, OA and stearidonic acid (C18:4 n-3) did not show differences in their content during growth. IVDMD and IVNDFD decreased linearly with increasing growth stage. The first summer cut of quinoa, whose lipid fraction is rich in ALA and other polyunsaturated FA, should be before shooting, since its nutritional quality deteriorates when cutting is delayed.

The nutritional value and fatty acid profile of the Guizotia abyssinica plant harvested for forage at seven growth stages were determined. Generally, growth stage resulted in an increase in neutral detergent fibre (NDF), acid detergent fibre, lignin, and indigestible NDF and a decrease in protein content, in vitro true digestibility and NDF digestibility. Among the main fatty acids (FA) in the plant during growth, ?-linolenic acid (C18:3 n-3) and linoleic acid (C18:2 n-6) were the most abundant (from 440 to 548 and from 154 to 195 g/kg of total FA, respectively). Some minor FAs showed no differences in their content during growth. The whole plant was characterised by a high proportion of polyunsaturated fatty acids, which made up between 696 and 764 g/kg of total FA, and a low proportion of saturated fatty acids. Niger is a forage plant with a good nutritional value and an interesting FA profile and should be harvested no later than the shooting stage of growth to ensure that the forage has high nutritive value and maintains a moderately high nutrient digestibility.

Com o objetivo de avaliar a digestibilidade in situ das frações fibrosas de silagens de seis híbridos de sorgo em diferentes estádios de maturação, foram utilizados quatro bovinos machos, fistulados no rúmen, castrados, mestiços Holandês-Zebu, alimentados com feno de gramínea à vontade. Amostras de silagens secas e moídas foram colocadas em sacos de náilon que foram introduzidos nas fístulas dos bovinos. Após períodos de incubação de 6, 12, 24, 48, 72 e 96 horas, os sacos foram removidos e as amostras de um mesmo híbrido, animal e período de incubação foram transformadas em um "pool" homogêneo, moído e armazenado para análises posteriores das frações fibrosas. O delineamento experimental utilizado foi o de parcelas sub-subdivididas no qual as parcelas eram as silagens de híbridos, as sub-parcelas os estádios de maturação e as sub-sub-parcelas os períodos de incubação. No corte 1, exceto nos tempos de incubação de 6, 24 e 96 horas, os híbridos não diferiram quanto ao desaparecimento médio de FDN. No corte 2 houve diferenças entre híbridos apenas no tempo de 12 e 96 horas e no corte 3, apenas no tempo de 12 horas. Em todos os híbridos registrou-se estabilização do processo fermentativo a partir de 72 horas, exceto nos híbridos BR 304 nos cortes 1 e 3 e BRS 701 no corte 3. Não houve diferenças entre híbridos quanto ao desaparecimento médio de FDA em nenhum dos tempos estudados, exceto para o tempo de 96 horas no corte 1 e no tempo de 72 horas no corte 3. As curvas de degradação demonstraram tendência de estabilização do processo fermentativo a partir de 72 horas, à exceção dos híbridos BR 304 no corte 1 e BRS 701 no corte 3. A participação de grãos nas silagens não influenciou o desaparecimento das frações fibrosas. Entretanto, houve influência do estádio de maturação das plantas sobre sua degradabilidade efetiva, favorecendo os cortes mais precoces.In order to evaluate the in situ digestibility of fibrous fractions of silages of six sorghum genotypes in different stages of maturation, four fistulated male crossbred Holstein-Zebu bovines fed with grass hay ad libitum were used. Silages samples were dried and milled and then placed in nylon bags and introduced into the rumen through the fistulas. After different times of incubation (6, 12, 24, 48, 72 and 96 hours later), the nylon bags were removed, the samples from the same genotype, animal and time of incubation were transformed into a homogenous pool and milled, and then stored for further analysis of fibrous fractions. It was used the split-plot design, in which the parcels were the silages of different genotypes, the sub-parcels were the periods of harvesting and the sub-sub-parcels were the periods of incubation. In the period 1, except at 6, 24 and 96 hours of incubation, no differences among hybrids related to the NDF mean disappearance were found. In the period 2, differences among hybrids just after 12 and 96 hours of incubation, and in the period 3, just after 12 hours of incubation were found. There was stabilization of the fermentative processes from the 72 hours period ahead, except in the BR 304 hybrid at the periods 1 and 3 and BRS 701 at the period 3. No differences among hybrids related to the ADF mean disappearance at any time, except for the 96 hours period in period 1 and the 72 hours period in period 3 were observed. The degradation graphics demonstrate a stabilization tendency of the fermentative process at the 72 hours period, except for the BR 304 hybrid in the period 1 and the BRS 701 hybrid in the period 3. The percentage of grains in silages did not influence the disappearance of the fibrous fractions. However, the stage of maturation of the plant influenced the effective degradability of fibrous fractions, benefiting early stages.

The fatty acid (FA) profile, chemical composition, gross energy and organic matter digestibility of chia ( Salvia hispanica L.) have been determined in the seed and in the plant collected at five progressive morphological stages from early vegetative to budding stage. The FA analyses disclosed quantitative differences between the plant stages that were characterised by a high percentage of polyunsaturated fatty acids (PUFA), which made up from 752 to 623 g/kg of the total FA of the plant during the growth cycle. The α-linolenic acid (ALA, C 18:3 n –3 ) decreased from 649 g/kg, at the early vegetative stage, to 499 g/kg of the total FA, at the budding stage, while all the other FAs increased with increasing growth stage. The chia seed FAs were also highly unsaturated, with their main components being ALA (641 g/kg of the total FA) and linoleic acid (LA, C 18:2 n –6 ; 188 g/kg of the total FA). The evolution of the quality of chia is closely related to the ageing of the plant. The chia plant provides a forage with a good nutritive value when harvested at a stage before the shooting period. After this, the nutritional quality of the plant considerably decreases with an increase in the fibrous fractions and a dramatical decrease of the crude protein content.

Com o objetivo de avaliar a digestibilidade in situ das frações fibrosas de silagens de seis híbridos de sorgo em diferentes estádios de maturação, foram utilizados quatro bovinos machos, fistulados no rúmen, castrados, mestiços Holandês-Zebu, alimentados com feno de gramínea à vontade. Amostras de silagens secas e moídas foram colocadas em sacos de náilon que foram introduzidos nas fístulas dos bovinos. Após períodos de incubação de 6, 12, 24, 48, 72 e 96 horas, os sacos foram removidos e as amostras de um mesmo híbrido, animal e período de incubação foram transformadas em um "pool" homogêneo, moído e armazenado para análises posteriores das frações fibrosas. O delineamento experimental utilizado foi o de parcelas sub-subdivididas no qual as parcelas eram as silagens de híbridos, as sub-parcelas os estádios de maturação e as sub-sub-parcelas os períodos de incubação. No corte 1, exceto nos tempos de incubação de 6, 24 e 96 horas, os híbridos não diferiram quanto ao desaparecimento médio de FDN. No corte 2 houve diferenças entre híbridos apenas no tempo de 12 e 96 horas e no corte 3, apenas no tempo de 12 horas. Em todos os híbridos registrou-se estabilização do processo fermentativo a partir de 72 horas, exceto nos híbridos BR 304 nos cortes 1 e 3 e BRS 701 no corte 3. Não houve diferenças entre híbridos quanto ao desaparecimento médio de FDA em nenhum dos tempos estudados, exceto para o tempo de 96 horas no corte 1 e no tempo de 72 horas no corte 3. As curvas de degradação demonstraram tendência de estabilização do processo fermentativo a partir de 72 horas, à exceção dos híbridos BR 304 no corte 1 e BRS 701 no corte 3. A participação de grãos nas silagens não influenciou o desaparecimento das frações fibrosas. Entretanto, houve influência do estádio de maturação das plantas sobre sua degradabilidade efetiva, favorecendo os cortes mais precoces. In order to evaluate the in situ digestibility of fibrous fractions of silages of six sorghum genotypes in different stages of maturation, four fistulated male crossbred Holstein-Zebu bovines fed with grass hay ad libitum were used. Silages samples were dried and milled and then placed in nylon bags and introduced into the rumen through the fistulas. After different times of incubation (6, 12, 24, 48, 72 and 96 hours later), the nylon bags were removed, the samples from the same genotype, animal and time of incubation were transformed into a homogenous pool and milled, and then stored for further analysis of fibrous fractions. It was used the split-plot design, in which the parcels were the silages of different genotypes, the sub-parcels were the periods of harvesting and the sub-sub-parcels were the periods of incubation. In the period 1, except at 6, 24 and 96 hours of incubation, no differences among hybrids related to the NDF mean disappearance were found. In the period 2, differences among hybrids just after 12 and 96 hours of incubation, and in the period 3, just after 12 hours of incubation were found. There was stabilization of the fermentative processes from the 72 hours period ahead, except in the BR 304 hybrid at the periods 1 and 3 and BRS 701 at the period 3. No differences among hybrids related to the ADF mean disappearance at any time, except for the 96 hours period in period 1 and the 72 hours period in period 3 were observed. The degradation graphics demonstrate a stabilization tendency of the fermentative process at the 72 hours period, except for the BR 304 hybrid in the period 1 and the BRS 701 hybrid in the period 3. The percentage of grains in silages did not influence the disappearance of the fibrous fractions. However, the stage of maturation of the plant influenced the effective degradability of fibrous fractions, benefiting early stages.

Forage Brassica spp. have high quality and digestibility. It is important to define the nutritive quality and fatty acid (FA) profile of this type of crop during growth. The quality of Brassica forage changes according to its growth stage and an understanding of its evolution would enable cutting times to be planned, in order to optimise forage utilisation and to identify new sources of FAs for herbivores. Our aim was to study changes in the chemical composition, in vitro dry matter digestibility (IVDMD) and neutral detergent fibre digestibility (IVNDFD), gross energy, and FA profile of Ravizzone (RAV) (Brassica campestris L. var. Oleifera) seeds and plant samples collected from the vegetative through to the ripening stage. The evolution of RAV quality during growth is characterised by a progressive decrease in crude protein and IVDMD and an increase in dry matter and fibrous fractions, while the lowest value of IVNDFD was reached at the bud stage. The main FAs of the plant during growth were: ?-linolenic acid (ALA, C18:3n-3), linoleic acid (LA, C18:2n-6), cis-10 heptadecenoic acid (C17:1), and palmitic acid (PA, C16:0). The most abundant FAs in the seed were oleic acid (OA, C18:1n-9), LA, ALA and PA. The chemical composition and FA profile of RAV is closely connected with the development of the plant. A forage with good nutritive value is still obtained even when harvesting RAV at the flower stage