Raphael Pavesi Araújo

Soybean in different forms of processing in the feeding of crossbred cows on brachiaria grass pastures

The objective was to evaluate intake and digestibility of nutrients, as well as milk production and composition of the milk from F1 Holstein × Gyr cows kept on pasture, supplemented with sugarcane and concentrate (28% CP). Five cows with 150±14 lactation days and average milk production of 7.1±2.1 kg/day were distributed in a 5 × 5 Latin square design. The treatments were: soybean meal-based concentrate; soy bean-based concentrate; ground soybean-based concentrate; roasted soybean-based concentrate; and ground, roasted soybean-based concentrate. Dry matter (DM), organic matter, crude protein (CP), neutral detergent fiber (NDF), total carbohydrates and total digestible nutrients intakes were not affected by the diet, but ether extract intake was higher for the animals fed soy bean-based diets than those fed soybean meal. The digestibility of DM, NDF and CP did not differ. The corrected milk yield differed between treatments; animals on the treatment with soy bean-based concentrate had the lowest production in relation to the others, which did not differ from each other. There was no difference between treatments for milk composition. Thus, soybean meal can be replaced by ground soy beans or roasted soy beans (ground or whole) in diets for low-yield cows reared on Brachiaria decumbens pastures with no harm to milkproduction or composition. Therefore, the use of these alternative raw materials is recommended whenever their inclusion represents lower feeding costs.

Slow-release urea in diets for lactating crossbred cows

The objective of this study was to evaluate the performance of F1 (Holstein × Zebu) cows in lactation according to different levels of substitution of soybean meal for a protein equivalent non-protein nitrogen originated from slow-release urea (SRU). Eight F1 (Holstein × Zebu) cows in the first third of lactation, with an average milk yield of 12.7 kg (±3.1 kg)/day and a live weight of 552 kg (±30 kg), were used. The experimental design was composed of two simultaneous 4 × 4 Latin squares, with the following treatments: 100% soybean meal and 0% SRU; 66% soybean meal and 34% SRU; 34% soybean meal and 66% SRU; and 0% soybean meal and 100% SRU. Sorghum silage, used as roughage, was supplied together with the concentrate. Feed intake and digestibility as well as milk yield and milk composition were measured. The obtained data were subjected to analysis of variance, adopting a 5% probability level. No intake variable showed significant differences among the treatments, and the mean values for the intakes of dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) were 18.35 2.62 and 5.85 kg/day, respectively. The results for apparent digestibility also did not show differences among treatments, with DM, CP and NDF averaging 58.16, 58.64 and 36.21%, respectively. Milk yield and composition were similar among the treatments. The average 4%-fat-corrected milk yield was 13.39 kg/animal day. Intake, digestibility and milk yield and composition variables are not changed according to the substitution of the soy protein for slow-release urea. Thus, for average-milk-yield crossbred.animals, this substitution depends on economic variables only.

Desempenho de vacas em lactação consumindo dietas contendo misturas de óleos essenciais

Objetivou-se com o presente trabalho avaliar os efeitos de uma mistura comercial de oleos essenciais (capsaicina, eugenol, cinamaldeido e carvacrol) microencapsulados com inclusoes crescentes (0; 1,5; 3,0 e 4,0g/dia) sobre o consumo, digestibilidade, desempenho e a composicao do leite de 20 vacas Holandesas primiparas confinadas em baias com cama de areia. Nao houve interacao entre os tratamentos e os periodos avaliados, e o efeito dos tratamentos nao foi significativo (P>0,05) para as variaveis consumo de materia seca, expresso em % PV e em kg/dia, proteina bruta (% PV), extrato etereo (% PV), fibra em detergente neutro (% PV), fibra em detergente acido (% PV); digestibilidade da materia seca (%), proteina bruta (%), extrato etereo (%), fibra em detergente neutro (%); producao de leite (kg) e seus componentes gordura (%), proteina (%), lactose (%), solidos totais (%), extrato seco desengordurado (%), contagem de celulas somaticas (log) e nitrogenio ureico (mg/dL). No entanto, avaliando separadamente os periodos testados, encontrou-se diminuicao significativa (P 0,05) para os teores de extrato seco desengordurado (%) e contagem de celulas somaticas (log). Pode-se concluir que a utilizacao de oleos essenciais contendo capsaicina, eugenol, cinamaldeido e carvacrol nao influencia o consumo, digestibilidade, producao e composicao do leite de vacas Holandesas primiparas.

Kinetics of ruminal passage rate of particles of signal grass silage, maize and intercropped

The purpose of this study was to evaluate the kinetics of ruminal passage rate of particles from the subsequent associations: corn and signal grass; corn, signal grass and Calopogonio; corn, signal grass and Macrotiloma; and corn, signal grass and Estilosantes. It was used four crossbred holstein-zebu cattle with the rumen tubed in order to determine the the kinetics of ruminal passage rate of particles. The feces were collected at the times zero (immediately after addition of fibers complexed with chromium), 1, 2, 4, 6, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 56 , 64, 72, 80, 88, 96, 120, 132, 144 and 192 hours. The profile parameters of passage rate estimative were adjusted according to robust regression procedures. The average time of particles retention in the raft (ATPR1); the average time in the rumen liquid phase (ATRLP2) and the average time of total ruminal retention (ATTRR) were adjusted for the passage kinetics and estimated with the NLIN procedure of SAS. From the observed results, may be suggested that the transference rate λ has an inverse behavior to the escape rate κ, the τ average values, the average retention time and average particles retention time in the rumen liquid phase (ATRLP2) were not statistically different. The feed characteristics after the raft escape and reach to ATRLP2, were very similar; (ATTRR), related to treatments, were not statistically different (P<0,05). There were observed small TMRR numerical differences in different foods. The corn and signal grass; corn, signal grass and calopogonio; corn, signal grass and macrotiloma, corn, signal grass and estilosantes silage fibers had similar rates ofλ, k, ATPR1, ATRLP2 and ATTRR. Therefore, the the kinetics of ruminal passage rate of particles is similar. Thus, the choice of the system should be based on other factors, such as viability of the management ease and silage cost.

Kinetics of transit and degradation of the fiber from guinea grass silages enriched with waste from soybean pre-cleaning

The objective was to study the kinetics of transit and degradation of the fiber from guinea grass and the waste from soybean pre-cleaning (WSPC), ensiled with different proportions of mass (0, 100, 150, and 200 g WSPC/kg total mass). Four crossbred (Gyr × Holstein), fistulated cattle with an average body mass of 400±50 kg were organized in a 4 × 4 Latin square experimental design. The fiber utilized in the study of the transit kinetics was stained with chromium mordant, whereas the in situ technique was adopted for the degradation kinetics. The level of inclusion of WSPC only affected the true digestibility and the mean retention time. The addition of waste from soybean pre-cleaning to the silage of guinea grass is beneficial, in terms of kinetics of digestion and passage, at up to levels close to 100 g/kg, because after this quantity the fiber digestion and passage in and through the reticulo-rumen are impaired and there may be alterations in the ruminal environment that will affect the use of silage by animals.

CHAPTER 2:The Biological Roles of Calcium: Nutrition, Diseases and Analysis

Calcium is an alkaline-earth metal with atomic number 20 and the fifth most abundant element by mass in the Earths crust, being one component of several common mineral salts. This mineral is important in plant physiology as well as to several metabolic and cellular functions of the human organism, as well as to the formation of bone tissues. Insufficient calcium intake may lead to the development of osteoporosis. On the other hand, the excessive ingestion of calcium increases the risk for renal calculus and intestinal constipation. The presence of calcium in the blood is regulated by vitamin D and by the hormones calcitonin and parathormone.