Fernando de Paula Leonel

A new approach about the digestion of fibers by ruminants

The decisive role of metallic cations in the formation of supramolecular clusters involving lignin, cellulose, and hemi-cellulose and its relationship to energy losses in ruminants associated with fibrous feed resources is still not well understood. Indeed, interactions between lignin, cellulose and metallic cations generate highly stable clusters that significantly decrease the capability of cellulase to break bonds between sugar units in order to facilitate the absorption of a great quantity of cellulose, which is ingested by ruminants as forage. Furthermore, several metallic cations cannot be absorbed as a consequence of the formation of coordinated ligations with the oxygen atoms of the lignocellulosic cluster. The loss of lignocellulose-metal clusters by ruminants is responsible for a substantial waste of nutrients, which is a significant problem in animal science. Moreover, the chemical structure of these relevant supramolecular systems is poorly understood. In the present review, we discussed this topic in detail in reference to relevant literature from the chemical and animal sciences in order to analyze the perspectives associated with the improvement of nutritional absorption from feed resources by ruminants.

Mineral deposition in tissues of cattle fed with different phosphates and relationships phosphorus: fluorine

Quarenta e nove novilhos machos foram distribuidos em delineamento casualizado, inicialmente com sete repeticoes por tratamento, sendo que, ao final do experimento, foram abatidos quatro animais por tratamento. Os tratamentos foram CONT: Dieta controle; FBC120: Fosfato Bicalcico 120:1 de relacao P:F; MBC60: Fosfato monobicalcico 60:1 de relacao P:F; FBC 30:1: Fosfato Bicalcico 30:1 de relacao P:F; SFT30: Super Fosfato Triplo 30:1 de relacao P:F; FBC10: Fosfato Bicalcico 10:1 de relacao P:F; CAR10: Concentrado de Rocha 10:1 de relacao P:F. Os fosfatos menos elaborados apresentaram maiores concentracoes de metais. Nos ossos, os teores de ferro, aluminio e chumbo foram maiores para a dieta FBC10, enquanto o cobre foi maior na dieta MBC60. Magnesio foi mais presente no figado de animais que consumiram a dieta FBC30, enquanto aluminio foi maior para SFT30, FBC10 e FBC120; cadmio e chumbo foram maiores para a dieta STF30. Os tratamentos nao influenciaram fosforo e fluor em coracao e musculos. O cromo foi mais presente no musculo de CAR10 e STF30 e o cadmio foi mais encontrado nos coracoes de CAR10. Nos rins, fosforo foi mais presente na dieta CAR10 e menor na dieta FBC10, enquanto aluminio foi maior na dieta FBC10 e menor na dieta FBC120 assim como os teores de cromo e chumbo foram maiores nos animais da dieta CAR10 e menores na dieta MBC60. Fontes alternativas de fosforo e baixas relacoes P:F aumentaram a deposicao de minerais em ossos e figado, sendo menor nos musculos.

Desempenho produtivo e parâmetros sanguíneos de vacas leiteiras em pastejo suplementadas com resíduos de feijão

The objective of this work was to evaluate the effect of dietary supplement bean residue on growth performance and blood parameters of dairy cows grazing. Eight crossbred cows weighing 500 kg were analyzed, distributed in 4×4 double Latin square, and fed with 134, 240, 348, and 449 g kg ‑1 of a supplementary diet of bean waste in the concentrated feed. The animals received the supplementation after milking in the morning and in the afternoon. The inclusion of bean residues did not change average body weights and body scores; however, it reduced the milk production. Fat, protein, lactose, and total solid contents (g kg ‑1 ) were not changed by bean waste inclusion. Blood glycose and cholesterol did not change before the offering of the concentrated feed diet, nor after four to six hours of feeding this diet. The inclusion of bean residues in the concentrated feed of dairy cows subjected to grazing, with a daily average production of 13 kg, reduces milk production. However, the use of these residues has little effect on milk composition and blood parameters.

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.

Factors affecting feed efficiency in dairy goats

The objective of this study was to present some factors affecting feed efficiency in dairy goats. To develop our work, individual and average data from performance experiments with lactating goats were used. The following variables were evaluated: gross feed efficiency, adjusted feed efficiency, dry matter intake, milk-yield, 3.5% fat-corrected milk yield, dry matter digestibility, dietary neutral detergent fiber content, different roughage-to-concentrate ratios and body weight. The statistical analyses involved the application of descriptive and dispersion measures besides Pearsons correlation coefficient and linear regression analysis. The analyzed variables were highly correlated with feed efficiency. The feed efficiency of lactating goats was affected by the milk fat correction, dry matter digestibility, dietary fiber content, proportion of roughage in the diet and body weight. Among these factors, standardization of the milk fat appeared to be the most efficient in correcting the feed efficiency in lactating goats. Correction of some of these factors implies greater precision in the measurement of feed efficiency.

Parâmetros sanguíneos de vacas leiteiras mantidas em pasto suplementadas com diferentes fontes proteicas

The present work aimed to evaluate the effect of supplementation with different protein sources in the diets for dairy cows kept on Brachiaria brizantha MG5 grass pasture on serum levels of the glucose, triglycerides, cholesterol and urea as well as on enzymes gama grutamil transferase, creatinine quinase and aminotransferase. We have evaluated the following protein sources: bean byproduct, soybean meal, sunflower meal and cottonseed meal. Eight crossbred cows (Holstein x Gir) were used, weighing 500±60.33 kg, average milk production of 14.85±3.28 kg/day, between the 60th and the 90th day of calving, by a simultaneous double 4 x 4 latin square design 4 x 4. Each experimental period lasted 15 days, of which the first 10 days were designed to animal adaptation and the final five days for data collection. There was an interaction effect (P 0.05) of protein sources for the triglycerides, cholesterol and urea levels, averaging 6.46±2.05, 182.43±37.52 and 38.20±12.29 mg/dL, respectively. There was a significant effect (P 0.05) serum enzyme levels of glutamine transferase, creatinine quinase and aminotransferase, averaging 26.76±8.02, 112.13±20.13 and 58.79±31.72 IU/L, respectively. The protein sources promoted changes on blood glucose with the sampling time, while sampling time altered triglycerides and urea levels. Changes to other blood metabolites were not observed.

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.

Blood and bone parameters of cattle fed diets containing different phosphates and phosphorus: fluorine relations

Forty-nine male calves were allotted in a randomized design, being that initially were performed seven replicates per treatment. At the end of the experiment were slaughtered four animals per treatment. The treatments were designed as following: CONT: control diet; DC120: Dicalcium Phosphate 120:1 ratio P: F; MDCP60: Monodicalcium Phosphate 60:1 ratio P: F; DC30: Dicalcium Phosphate 30:1 ratio P: F; TSP30: Triple Superphosphate 30:1 ratio P: F; DC10: Dicalcium Phosphate 10:1 ratio P: F; PRC10: phosphate rock concentrate of 10:1 of relation P: F. Alkaline phosphatase (ALP) of animals who consumed PRC10 diet was greater than the ALP of animals that consumed TSP30, DC10 and DC120. This result was obtained with animals with 650 days of confinement. The ALP of the animals that consumed PRC10 was greater at 866 days than in the animals consuming TSP30 and DC120 diets. The ash content was greater in the DC10 diet and the diets CAR10 and DC120 achieved the lowest value. The fluorine content in bone was higher in diet DC10, while the diets DC120, PRC10 and MDCP60 obtained the lower values. The area of Haversian canals and the relation Havers/Osteon area were higher in the diet DC30 and the lowest value was encountered in DC10. The mottled teeth were more intensely observed in the treatments DC10 and PRC10. It was concluded that high fluorine content in the diet increases the deposition of fluorine in bones, which negatively affects in the histological parameters of teeth and bones of beef cattle.