Kátia Cylene Guimarães

Substituição do Milho pela Farinha de Mandioca de Varredura em Dietas de Cabras em Lactação: Produção e Composição do Leite e Digestibilidade dos Nutrientes

The objectives of this work were to evaluate effects of replacing corn by cassava by-product meal, in diets of Saanen lactating goats, on milk production and composition (total solids and crude protein), nutrient apparent digestibility and total digestible nutrients (TDN) of diets. Four multiparous goats fitted with ruminal cannula, with 100 days of lactation, were used. The design was a 4 x 4 Latin square and treatments as following: 0, 33, 67 and 100% replacement of corn by cassava by-product [...]The objectives of this work were to evaluate effects of replacing corn by cassava by-product meal, in diets of Saanen lactating goats, on milk production and composition (total solids and crude protein), nutrient apparent digestibility and total digestible nutrients (TDN) of diets. Four multiparous goats fitted with ruminal cannula, with 100 days of lactation, were used. The design was a 4 x 4 Latin square and treatments as following: 0, 33, 67 and 100% replacement of corn by cassava by-product meal. Treatments did not affect intake, fecal flow and dry matter (DM), organic matter (OM), crude protein (CP), neutral fiber detergent (NDF) and non-fiber carbohydrate (NFC) total digestion (AD) and total digestibility (DIG). There was a linear fecal flow decrease and a starch digestibility increase with cassava by-product meal inclusion. TDN did not differ among diets with an average of 71.59%. There was a positive correlation (r = 0.9472) between OMDIG and TDN, making possible TDN estimation from the equation: TDN (%) = 0.8897OMDIG (%) + 10.9940 (R2 = 0.8972). Cassava by-product inclusion did not affect milk production and composition (total solids and crude protein). These results permit to recommend inclusion of cassava by-product in goat lactating diets, in total replacement of corn without problems related to nutrient digestibility and milk production.

Coeficiente de digestibilidade e características ruminais de bovinos alimentados com rações contendo resíduo de cervejaria fermentado

The objective of the present study was to evaluate the partial and total digestibility coefficient (DC) of the nutrients, ruminal pH, ammonia nitrogen (N-NH3) concentration in the ruminal fluid and microbial efficiency synthesis in bovines fed rations containing 0, 8, 16 and 24% of brewers grains. The brewer grains were ensiled in surface silo (5,000 kg). Four Holstein cattle (480 ± 100 kg of body weight) fitted with ruminal and duodenal cannulas, were distributed to 4 × 4 Latin square design. The mean DM intake of animals was 1.7% BW. Total and ruminal DC of the nutrients did not differ among the levels of BG used in the rations. The levels of BG in the rations showed a linearly increased on the intestinal DC dry matter and TC, as % of that reached the compartment. There was no effect of levels of BG in rations on pH and N-NH3 concentration in the ruminal fluid. The levels of RCF in diets did not affect the microbial efficiency synthesis in g N-Mic/kg of rumen apparent degradable organic matter and rumen truly degradable organic matter. The inclusion of up to 24% of BG (%DM) cattle feed does not alter the processes of rumen fermentation and digestion of nutrients.

Influence of starch and casein administered postruminally on small intestinal sodium-glucose cotransport activity and expression

Twenty-four Holstein steer calves (88 ± 3kg) with abomasal catheters were randomly assigned within blocks to one of four treatments. The treatments consisted of four abomasal infusions: water (control), 4 g/kg BW.d-1 of partially hydrolyzed starch (SH), 0.6 g/kg BW.d-1 of casein, and a mix of SH + casein. The small intestine was collected and five equidistan, 1m sites were identified (duodenum, jejunum 1, jejunum 2 jejunum 3 and ileum). Maltase specific activity in mucosal homogenate and brush border membrane vesicles, SGLT1 protein abundance, and sodium-dependent glucose uptake in brush border membrane vesicles did not differ between the calves receiving different abomasal infusion treatments. However, maltase specific activity in homogenates and brush border membrane vesicles increased four-fold from the duodenum to the first jejunal site before declining steadily towards the ileum (p=0.0145 p=0.0020, respectively). The SGLT1 abundance differed by intestinal sampling site (p=0.0162). These data indicated that cattle might not have the ability to alter the capacity for glucose uptake when challenged with different substrates and that the regulation of SGLT1 expression could differ between bovine and other species.

Efeito do período experimental sobre a fermentação ruminal e eficiência de síntese microbiana em bovinos alimentados com dois níveis de volumosos

The objectives of this research were to evaluate the effects of two forage levels and two experimental periods on the microbial efficiency, ruminal ammonia concentration, the ruminal pH, duodenal nitrogen (N) flux and digestibility. Four Holstein steers, two years old and 340 kg of body weight, ruminally and duodenally cannulated, were used. The experimental design was a 4 x 4 latin square and animals received four treatments as folowing: two levels of forage (70 and 30%) and two experimental periods (14 and 21 days). There were effects of the forage level on the ruminal ammonia concentrations and pH. There was effect of experimental period on the intake of N. The apparent microbial efficiency synthesis ranged from 29.3 to 32.0 g microbial N/ kg OMDR. The minimum pH for high forage diet (70%) was 6.5 and for low forage diet (30%) was 6.2. The maximum ruminal ammonia concentration of 16.9 mg/100 mL was obtained for the level of 70% of forage and 18.9 mg/100 mL of ruminal fluid to the level of 30% of forage.The objectives of this research were to evaluate the effects of two forage levels and two experimental periods on the microbial efficiency, ruminal ammonia concentration, the ruminal pH, duodenal nitrogen (N) flux and digestibility. Four Holstein steers, two years old and 340 kg of body weight, ruminally and duodenally cannulated, were used. The experimental design was a 4 x 4 latin square and animals received four treatments as folowing: two levels of forage (70 and 30%) and two experimental periods (14 and 21 days). There were effects of the forage level on the ruminal ammonia concentrations and pH. There was effect of experimental period on the intake of N. The apparent microbial efficiency synthesis ranged from 29.3 to 32.0 g microbial N/ kg OMDR. The minimum pH for high forage diet (70%) was 6.5 and for low forage diet (30%) was 6.2. The maximum ruminal ammonia concentration of 16.9 mg/100 mL was obtained for the level of 70% of forage and 18.9 mg/100 mL of ruminal fluid to the level of 30% of forage.

Replacement of dicalcium phosphate by rock phosphate in cattle diets: nutrients digestibility, plasma parameters, ruminal fermentation and microbial synthesis efficiency

This study was conducted in order to evaluate the effects of replacing dicalcium phosphate by rock phosphate in diets of growing steers. It was determined the following aspects: apparent digestibility of diets; phosphorus (P), calcium and fluorine apparent absorption; ruminal pH; ruminal ammonia concentration; microbial efficiency and plasma P. Five rumen fistulated Holstein steers weighting 275 - 283 kg were used. Experimental design was a 5 × 5 Latin square and diets consisted of 0, 25, 50, 75 and 100% of dicalcium phosphate replacement by rock phosphate in the mineral supplement. Addition of rock phosphate in the diets produced a linear increase on intake, rumen outflow and fecal output and total disappearance of fluorine. Diets did not differ to apparent absorption of calcium as well as dry matter, organic matter, crude protein, neutral detergent fiber and non-fiber carbohydrates intake, excretion, digestion and partial and total apparent digestibility. Plasma phosphorus was not influenced by diets and the average was 5.93 mg/dL. There was no difference for ruminal pH and ruminal ammonia concentration. Dicalcium phosphate replacement did not affect apparent and true protein microbial synthesis. Total replacement of dicalcium phosphate by rock phosphate in growing steer mineral supplement did not affect ruminal environment and protein synthesis in rumen. Considering this, dicalcium phosphate replacement in growing steer diets decreases P absorption and depending on its requirements it should be carefully seen.

Efeito do período experimental sobre a digestão parcial e total em bovinos alimentados com dois níveis de volumosos

Os objetivos deste trabalho foram avaliar os efeitos de dois periodos experimentais e dois niveis de volumosos na dieta sobre a digestibilidade total e parcial da materia seca (MS), materia orgânica (MO), proteina bruta (PB), fibra em detergente acido (FDA), fibra em detergente neutro (FDN), energia bruta (EB) e amido. Foram utilizados quatro novilhos da raca Holandes Preto e Branco, com dois anos de idade e 340 kg de peso vivo e canulados no rumen e duodeno. O delineamento experimental utilizado foi o quadrado latino 4 x 4, em que os animais receberam quatro tratamentos, que consistiram de dois niveis de volumosos (30 e 70%) e dois periodos experimentais (14 e 21 dias). Houve efeito significativo do nivel de volumoso sobre a digestibilidade ruminal de FDA e FDN, a digestibilidade intestinal e total da MS, MO, PB e amido e a digestibilidade total da EB. Nao houve efeito do periodo experimental sobre os coeficientes de digestibilidade dos nutrientes avaliados. Conclui-se que a utilizacao de periodo experimental de 14 dias, em experimentos de digestao, e viavel, quando se utiliza feno como fonte de volumoso.