The study evaluated the effects of supplementing cashew nut shell liquid (CNSL) in the diet of lactating dairy cows on the intake, nutrient digestibility, milk yield and composition, and fatty acids composition of milk fat. Four Holstein cows (600±43 kg) were used in a 4 x 4 Latin square design with 21 days experimental periods. Experimental treatments consisted of CNSL inclusion in a total mixed ration (dry matter basis), as follows: 1) CNSL 0% (control, CON), 2) CNSL 0.012% (0.012), 3) CNSL 0.024% (0.024) and 4) CNSL 0.036% (0.036). Dry matter and nutrients intake, apparent digestibility of nutrients, fat corrected milk yield and milk composition were not affected (p > 0.05) by the inclusion of CNSL in the ration. CNSL linearly decreased the C6:0 concentration (p < 0.02), produced a quadratic response on C13:1n-5 concentration (p < 0.03) and a linear increase on C16:1n-7 concentration (p < 0.04). Results show that an intake of up to 7 g cow-1 day-1 (0.036%) of CNSL may alter the milk fatty acid composition but does not influence intake, nutrient digestibility and milk yield.

The aim of this study was to evaluate the chemical composition, fractionation of carbohydrates and nitrogen compounds, degradation parameters, and in vitro ruminal fermentation of cactus pear genotypes. The experiment was conducted in a completely randomized design with 4 cactus pear genotypes and 4 replicates. The evaluated cactus pear genotypes were: Miúda (Nopalea cochenillifera Salm Dyck), IPA Sertânia (Nopalea cochenillifera), Gigante (Opuntia ficus indica Mill), and Orelha de Elefante Mexicana (Opuntia stricta Haw), all in natura. Samples were randomly collected at different points in the experimental area. Whole plants were collected 24 months after field crop establishment. N. cochenillifera Salm Dyck presented the highest dry matter, acid detergent insoluble protein, non-fibrous carbohydrate, total digestible nutrients, digestible energy, total carbohydrates, and fractions A + B1 (P<0.05), while presenting lower neutral detergent fiber corrected for ash and protein, acid detergent fiber, and cellulose in relation to the other genotypes studied (P<0.05). The in vitro true digestibility of neutral detergent fiber was high for the genotypes N. cochenillifera Salm Dyck and N. cochenillifera Dyck, which also presented high in vitro total gas production (P<0.05). The cactus pear genotypes show adequate chemical characteristics to be composed part of diets offered to ruminants. However, supplementation is necessary to increase the dry matter and fiber contents. The Nopalea cochenillifera Salm Dyck genotype presented the highest proportions of total digestible nutrients, non-fibrous carbohydrates, non-protein nitrogen, unavailable nitrogen fraction total, and high gas production in relation to the other analyzed genotypes 24 months after field crop establishment.

The objective of this study was to evaluate the effect of the inclusion of sunflower cake replacing soybean meal in beef cattle diets on the in vitro digestibility of dry matter (IVDDM), organic matter (IVDOM), crude protein (IVDCP) and the ruminal fermentation kinetics and parameters. The experiment was analyzed according to a completely randomized design. The treatments consisted of four levels of sunflower cake, 0, 200, 400, 600 g kg-1, replacing soybean meal in the concentrate of beef cattle diets. The coefficients of IVDDM, IVDOM and IVDCP presented a quadratic effect with the addition of sunflower cake. The soluble fraction (fraction B) degradation rate and total gas production decreased linearly with the inclusion of sunflower cake. Values of pH in ruminal fluid were higher for levels 0, 200 and 600 g kg-1 sunflower cake. Sunflower cake can replace soybean meal by up to 280 g kg-1 in the concentrate of beef cattle diets, improving the in vitro digestibility of dry matter organic, matter and crude protein. Levels above 400 g kg-1 reduce ruminal digestion rate, digestibility and release of final fermentation products.

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This study aimed to evaluate the chemical and minerals composition, fractions of carbohydrate and nitrogen compounds, kinetics of degradation and in vitro gas production of native cactus species of the brazilian Semiarid. The experiment was conducted in a completely randomized design, with five native cactus species and 4 replications per species were randomly selected. The native cactus species evaluated were: Cereus jamacaru DC., Melocactus bahiensis Br. Et Rose Werderm, Opuntia inamoene K. Schum, Pilosocereus gounellei (A. Weber ex K. Schum) Bly ex Rowl and Pilosocereus pachycladus Ritter, all in natura. The native cactus species showed differences for chemical and mineral compositions (P <0.05). The nitrogenous components, C. jamacaru cactaceae presented higher contents of fractions A (228.1 g/kg CP) and B3 (241.7 g/kg CP) and smaller fraction C (174.0 g/kg CP). For carbohydrate fraction C. jamacaru presented lower fractions A + B1 (412.2 g/kg TC) and C (38.2 g/kg TC) and high fraction B2 (549.7 g/kg TC) and low fraction C. The cactus C. jamacaru and M. bahiensis presented a high PD (856.6 and 837.9 g/kg DM, respectively). The parameters a and b and the effective degradability present diferences (P<0.05) in function of 2% and 5% passage rate. The in vitro true digestibility of dry matter was above 700 g/kg of DM for all species. Cactus have high levels of potentially digestible fractions of total carbohydrates, indicating their importance as food for ruminants in created in the semiarid, where Caatinga vegetation is a basal resource.