Perfil metabólico proteico de vacas em lactação alimentadas com milho e ureia a pasto / Protein metabolic profile of dairy cows fed corn and urea pasture

Objetivou-se com este estudo avaliar os efeitos da substituição total do farelo de soja por milho e ureia sobre consumo e digestibilidade aparente da matéria seca, perfil metabólico proteico e balanço de nitrogênio de vacas mestiças em lactação em pastejo, com lotação intermitente de capim-mombaça (Panicum maximum). Foram utilizadas 12 vacas mestiças em lactação, com peso corporal médio inicial de 473,0+45,0kg, período de lactação médio de 95,0+42,2 dias e produção de leite de média inicial de 14,1+1,9kg/dia. As vacas eram primíparas e multíparas, mestiças de Girolando, Pardo-Suíço e Jersey. Os tratamentos consistiram em quatro níveis de substituição do farelo de soja por milho e ureia (0; 33; 66; 100% na matéria seca - MS). O capim-mombaça apresentou teor médio de proteína bruta e fibra em detergente neutro de 19 e 59% na MS, respectivamente. A substituição do farelo de soja por milho e ureia não alterou o consumo e a digestibilidade aparente da MS. As concentrações de ureia e N-ureico plasmáticos foram alteradas pela substituição do farelo de soja por milho e ureia. O balanço de nitrogênio foi positivo e não foi alterado com as substituições. Para vacas mestiças produzindo, em média, 12,5kg/dia e mantidas em pasto de qualidade, pode se substituir totalmente o farelo de soja por milho e ureia.(AU)

The objective of this study was to evaluate the effects of total replacement of corn by soybean meal and urea on intake and apparent digestibility of dry matter, protein metabolic profile, and nitrogen balance of lactating crossbred cows grazing with intermittent stocking Mombasa grass (Panicum maximum). Twelve milking cows were distributed in a triple 4 x 4 latin design, with a mean initial body weight of 473,0+45,0kg, average lactation period of 95,0+42,2 days and milk production of initial mean of 14,1+1,9kg/day. Cows were primiparous and multiparous. The treatments consisted of four levels of substitution of soybean meal for corn and urea (0; 33; 66; 100% in dry matter - DM). The Mombasa grass showed an average content of crude protein and neutral detergent fiber of 19 and 59% in DM, respectively. The concentrations of urea and plasma urea nitrogen were altered by replacing soybean meal with corn and urea. Protein metabolic profile was changed with the replacement of soybean meal by corn and urea. The nitrogen balance was positive and has not changed with the replacements. For mixed-race cows producing an average of 12.5kg/day and kept in good-quality pastures, one can replace soybean meal totally with corn and urea.(AU)

Nephroprotective and Curative Assessment of an Aqueous Seed Extract of Parkia clappertoniana Keay in Gentamicin-induced Renal Damage in Sprague-dawley Rats.

Aim: To assess the nephroprotective and curative effects of an aqueous seed extract of Parkia clappertoniana on gentamicin-induced renal damage (GIRD) in Sprague-Dawley rats. Study Design: Experimental Place and Duration of Study: Department of Medical Laboratory, University of Cape Coast, Ghana between September, 2012 and May 2013. Methodology: In assessing nephro protective effect, rats were pretreated (10 days) with P. clappertoniana aqueous seed extract (1-2 g kg-1; p.o) prior to induction of renal damage by treatment with gentamicin (0.08g kg-1; p.o, for 8 days. Serum biochemical markers (Creatinine, Urea, Na+ and K+) and urine parameters (leukocyte, protein, specific gravity and pH) of renal damage were determined and compared with baseline values. In a curative study, GIRD in rats was treated with Normal Saline (2 ml kg-1; p.o), Losartan (0.05 g kg-1; p.o), or extract (1-2 g kg-1; p.o) for 14 days and serum and urine parameters determined for all treatments. Histopathology and changes in kidney weights for normal and treated rats in both studies were assessed. The extract was screened for DPPH radical scavenging activity. Results: The extract significantly (P ≤ .001) reduced elevated serum creatinine and urea secondary to GIRD (P ≤ .05) and significantly (P ≤ .05) reduced elevated serum Na+ but had no effect on K+. Elevated urine proteins and leucocytes secondary to GIRD was significantly (P ≤ .05) reduced; but had no significant effect on urine pH and specific gravity. Elevated kidney weights associated with GIRD was significantly (P≤ .01) reduced. Histopathological assessment revealed healing effect by extract to GIRD. Effects of the extract were similar to Losartan. Pretreatment with extract however had no significant effect on GIRD as serum and urine parameters, as well as kidney weights were significantly (P≤ .01) elevated on induction of renal damage. Conclusion: The aqueous seed extract of Parkia clappertoniana has curative but no nephroprotective effect on gentamicin-induced renal damage in Sprague-Dawley rats.

Efeito do nível nutricional antes e após a ovulação sobre a taxa de gestação e a prolificidade em ovelhas Santa Inês / Effect of the nutritional level before and after ovulation on pregnancy rate and prolificacy in Santa Ines ewes

Quarenta e três ovelhas foram distribuídas em quatro tratamentos em um delineamento de blocos casualizados. Os tratamentos consistiram no fornecimento de dietas de flushing, formuladas com farelo de soja (FFS) ou com glúten de milho e farelo de algodão (FGM+FA) por 28 dias antes da ovulação, seguido pelo fornecimento de dietas de flushing ou de uma dieta de mantença (DM) durante 28 dias após a ovulação: T1 - FFS antes e após a ovulação (n=12); T2 - FFS antes da ovulação e DM após (n=11); T3 - FGM+FA antes e após a ovulação (n=10); T4 - FGM+FA antes da ovulação e DM após (n=10). O ganho de peso e o peso final não diferiram (P>0,05) entre os animais dos tratamentos. O ECC final foi maior (P<0,05) nas ovelhas do tratamento T3 do que nas do tratamento T2. A concentração de N-ureico foi maior (P<0,05) nas ovelhas dos tratamentos T1 e T3 do que naquelas dos tratamentos T2 e T4. A taxa de gestação e a prolificidade não diferiram (P>0,05) entre os animais. As dietas de flushing antes da ovulação, seguidas pelo fornecimento destas mesmas dietas ou de uma dieta de mantença após a ovulação, não alteraram a taxa de gestação e a prolificidade.

Forty-tree ewes were assigned to four treatments in a randomized block design. The treatments consisted of two flushing diets, composed of soybean meal (SMF) or corn gluten and cottonseed meal (CG+CMF) furnished for 28 days before ovulation, and feeding with flushing diets or a maintenance diet (MD) for 28 days after ovulation: T1 - (SMF) before and after ovulation (n=12); T2 - SMF before ovulation and a MD after (n=11); T3 - CG+CMF before and after ovulation (n=10); T4 - CG+CMF before ovulation and MD after (n=10). The gain in BW and the final BW did not differ (P>0,05) between treatments. The final BC was higher (P>0,05) in ewes in T3 treatment than in those in treatment T2. The urea N concentration was higher (P<0,05) in ewes in treatments T1 and T3 than those in treatments T2 and T4. The pregnancy rate and prolificacy did not differ (P>0,05) between treatments. The flushing diets before ovulation and feeding with this same diet or a maintenance diet after ovulation did not alter the pregnancy rate and prolificacy.

Adición de glucomananos a dietas con baja proteína a base de sorgo-pasta de soya para cerdos en crecimiento y finalización / Addition of glucomannans to low-protein diets based on sorghum-soybean meal for growing and finishing pigs

Los cerdos en engorde alimentados con dietas sorgo-pasta de soya con baja proteína (DBP) presentan resultados productivos inconsistentes; en ocasiones, las variables productivas se mantienen, y en otras se deterioran. Además, siendo el sorgo el ingrediente en mayor cantidad, es probable que la dieta contenga mayor concentración de micotoxinas que en dietas estándar o en dietas formuladas con maíz. Por ello, se realizaron dos experimentos con cerdos en crecimiento y finalización, adicionando un secuestrante de micotoxinas (SECM) a dietas estándar y DBP para determinar su efecto en la respuesta productiva, características de la canal y urea en plasma. En el experimento de crecimiento se utilizaron 40 cerdos (machos castrados; 22,18 ± 0,82 kg) en un diseño de bloques completos al azar con arreglo factorial (2×4): dos niveles de proteína cruda (PC: 16; y 11,5%) y cuatro del SECM (0; 0,5; 1,0; 1,5 kg t-1), con cinco repeticiones por tratamiento. La reducción de PC disminuyó (P£0,05) la ganancia diaria de peso (GDP) y de carne magra (GCM), e incrementó (P£0,05) la conversión alimenticia (CA). En el experimento de finalización también se utilizaron 40 cerdos (machos castrados; 49,48 ± 1,10 kg). El diseño experimental fue similar al del experimento de crecimiento (14 y 9,5% PC; 0; 0,5; 1,0 y 1,5 kg t-1 SECM) y cinco repeticiones por tratamiento. La reducción de PC disminuyó (P£0,05) GDP, consumo de alimento (CAL) y GCM. En ambos experimentos, el SECM no mejoró las variables de respuesta en cerdos alimentados con DBP. Se concluye que la adición de SECM en DBP no mejora las variables productivas, pero mantiene las características de la canal, aunque reduce la GCM.

The growth performance of fattening pigs fed sorghum-soybean meal, low-protein diets (LPD) has been inconsistent; some times the productive variables do not change, but other times they are deteriorated. In addition, because the sorghum grain represents the main ingredient, it is likely that the diet has higher amounts of mycotoxins than standard diets or diets formulated with corn grain. So, two experiments were conducted with growing-finishing pigs to determine the effect of a mycotoxin sequestrant (MSEQ) added to standard or LPD on growth performance, carcass characteristics, and plasma urea nitrogen concentration. In the growing experiment, 40 growing (22.18 ± 0.82 kg) barrows were used in a randomized complete block design in a factorial (2×4) arrangement: two levels of crude protein (CP: 16 and 11.5%) and four levels of micotixins sequestrant (glucomannans; 0, 0.5, 1.0, 1.5 kg t-1), with five replicates per treatment. Lowering CP reduced (P£0.05) average daily gain (ADG) and fat free lean gain (FFLG), and increased (P£0,05) feed:gain ratio. In the finishing experiment, 40 finishing (49.48 ± 1.10 kg) barrows were used in a randomized complete block design in a factorial (2×4) arrangement: two levels of CP (14 and 9.5%) and four levels of micotoxins sequestrant (glucomannans; 0, 0.5, 1.0, 1.5 kg t-1), with five replicates per treatment. Diminishing CP reduced (P£0.05) ADG, average daily feed intake, and FFLG. The addition of glucomannans to low-protein diets did not affect growth performance in both experiments. It was concluded that adding glucomannans as mycotoxins sequestrant does not improve productive variables in pigs fed low-protein diets, but it produces similar carcass characteristics as in pigs fed standard diet, except the lower FFLG.

Respuesta productiva y concentración de urea en plasma de cerdos en crecimiento alimentados con dietas sorgo-pasta de soya con baja proteína / Growth performance and plasma urea concentration of growing pigs fed sorghum-soybean meal, low-protein diets

The dietary crude protein (CP) can be reduced by four percentage units when corn-soybean meal (SBM) and crystalline amino acids (AA) are used to formulate diets for growing pigs. With sorghum the results have not been conclusive. Therefore, two experiments were conducted to determine the lowest CP value in sorghum-SBM, AA supplemented diets, using plasma urea nitrogen (PUN), growth performance, and carcass characteristics as the response criteria. In Experiment 1, the percentage of CP in the treatments was as follows: T1) 16.0, control diet; T2) 14.5; T3) 13.0; and T4) 11.5. Eight gilts were used in a cross-over design with four periods of 7 days each. Blood samples were collected the last day of the period to determine PUN. Several regression models were used to obtain the best prediction of PUN. The lowest PUN indicated that CP can be reduced from 16 to 11.5%. The best regression model was the nonlineal exponential, which can predict that the minimum plasma urea concentration is obtained with 10.48% of CP. In Experiment 2, the percentage of CP and metabolizable energy Mcal kg-1) were as follows: T1) 16, 3.265, control; T2) 16, 3.165; T3) 14.5, 3.265; T4) 14.5, 3.165; T5) 11.5, 3.265; and T6) 11.5, 3.165. Thirty barrows were assigned in a completely randomized design with a 3 × 2 factorial arrangement, six treatments and five replicates of one barrow (individually penned) for each treatment. The lowest CP reduced the average daily gain, feed gain ratio, and PUN. The lowest ME reduced the feed gain ratio. These results indicate that reducing CP diminishes PUN, although some productive variables are affected.

La proteína cruda (PC) puede reducirse cuatro unidades porcentuales cuando se utiliza maíz-pasta de soya y aminoácidos (AA) para cerdos en crecimiento. Con sorgo no se han obtenido resultados concluyentes. Por ello se realizaron dos experimentos para determinar el porcentaje mínimo de PC en dietas sorgo-pasta de soya adicionadas con AA, con base en la concentración de urea en plasma de cerdos en crecimiento, y su respuesta productiva. En el Experimento 1, el porcentaje de PC en los tratamientos fue: T1) testigo, 16.0; T2) 14.5; T3) 13.0; y T4) 11.5. Se utilizaron ocho cerdas en un diseño cruzado (cross-over), con cuatro periodos de siete días. El último día de cada periodo se obtuvo sangre para determinar la concentración de urea. Se utilizaron varios modelos de regresión para obtener el que mejor predijera la concentración de urea. El menor nivel de urea indicó que la proteína puede reducirse de 16% hasta 11.5%. El mejor modelo de regresión fue el no lineal exponencial, con el que se puede predecir que la mínima concentración de urea se obtiene con 10.48% de PC. En el Experimento 2, los porcentajes de PC y las Mcal EM kg-1 fueron: T1) testigo, 16, 3.265; T2) 16, 3.165; T3) 14.5, 3.265; T4) 14.5, 3.165; T5) 11.5, 3.265; y T6) 11.5, 3.165, que se proporcionaron a 30 cerdos machos castrados (cinco repeticiones por tratamiento), alojados individualmente, en un diseño completamente al azar con arreglo factorial 3 × 2, con seis tratamientos y cinco repeticiones por tratamiento. La menor PC redujo la GDP, la conversión alimenticia y la urea en plasma. La menor EM redujo la conversión alimenticia. Lo anterior indica que disminuir la proteína reduce la urea en plasma, aunque se afectan algunas variables productivas.