Which oilseed meal provides a higher yield and better nutrient profile of milk in grazing cows?

This study aims to verify which of the oilseed meals will provide a higher milk production efficiency and milk nutrient profile in grazing cows to optimize the production system and improve milk nutrients for the benefit of nutrition and human health. A Latin square experiment was conducted with 12 cows for 84 days, fed Tanzania grass, and concentrated with cottonseed meal (CotM), sunflower meal (SunM), soybean meal (SoyM) and peanut meal (PeaM). SunM tended to have a higher production of 3.5% fat milk and higher milk urea nitrogen compared with the other treatments. SunM tended to have higher amount of fat in the milk compared with SoyM. PeaM tended to have lower fatty acids C13:0, C15:0 anteiso, C15:0 in milk compared with SunM. PeaM tended to have lower C16:0 and C17:0 iso compared with SoyM and CotM. PeaM had lower C18:1trans in comparison to the other meals. The addition of SoyM tended to have higher C18:1 cis15 compared with PeaM and tended to have lower thrombogenicity index compared with CotM and PeaM. Aiming at milk health in pasture production systems, SoyM presented the best nutritional quality of the lipid fraction. For productivity and fat yield, SunM had better results.

Efeitos da fonte de enxofre sobre a população de protozoários e degradabilidade no rúmen / Effects of sulfur source on protozoa population and ruminal degradability

Estudaram-se os efeitos de fontes de enxofre na dieta sobre os parâmetros ruminais de bovinos Nelore, utilizando-se oito novilhos canulados no rúmen e submetidos a quatro tratamentos, segundo a fonte de enxofre. Os animais do grupo-controle não receberam suplementação de enxofre. Os dos outros três grupos receberam flor de enxofre ou metionina ou carboquelatado, como suplementação. Os animais foram arraçoados com dieta total, utilizando cana-de-açúcar picada como volumoso. O período experimental foi de 76 dias, dividido em quatro subperíodos de 19 dias, dos quais 14 eram para adaptação à dieta e cinco para as colheitas. Não foram encontradas diferenças entre as fontes de enxofre na degradabilidade da matéria seca, proteína bruta e fibras em detergente ácido e neutro e no pH ruminal. O tratamento com carboquelatado resultou em maior número de protozoários ciliados e o tratamento metionina em menor contagem. O carboquelatado pode ser uma boa alternativa para a suplementação de enxofre para bovinos em confinamento.

This research was carried out at FZEA/USP to compare the effects of different sulphur sources in diets of Nellore cattle on ruminal parameters. Eight steers were rumen cannulated and submitted to four treatments, using the following sulphur sources: control (no supplement), elemental sulphur, methionine, and carboquelated. Animals were fed a total ration using sugarcane as the roughage. The proportion roughage:concentrate was 40:60. The experimental period lasted 76 days, divided in four 19-days sub-periods. The first 14 days of each sub-period were used to adapt the animals to the diet and the last five days to collect the samples. During the sample period, ruminal liquid was sampled to protozoa count and pH determination. Also, nylon bags were incubated in rumen to determinate the degradability of dietary dry matter, crude protein, and acid and neutral detergent fiber. Treatments did not affect dietary dry matter, crude protein, acid and neutral detergent fiber degradability, and the ruminal pH. However, carboquelated provided the higher total amount of ciliate protozoa and methionine provided the lowest values. Carboquelated can be a good alternative to supplement sulphur to bovines in a feedlot.

Influência do balanco cátion-aniônico da dieta no rúmen e no desempenho de ovinos / Influence of dietary cation-anion balance on rumen and performance variables in sheep

Estudou-se o efeito do balanco cátion-aniônico da dieta (BCAD) no desempenho animal e na fermentacão ruminal, utilizando-se 25 carneiros machos, da raca Santa Inês, durante 75 dias. O delineamento experimental foi em blocos ao acaso, com cinco tratamentos. Para a manipulacão do BCAD, foram adicionados sulfato de amônio e bicarbonato de sódio, obtendo-se os seguintes tratamentos: -160, -40, 140, 250 e 500 mEq/kg de matéria seca. O aumento do BCAD resultou em aumentos da ingestão de matéria seca, do ganho diário, da eficiência alimentar e do pH ruminal (P<0,05). O perfil de ácidos graxos ruminais não foi afetado pelo BCAD.

Avaliaçäo de colheita de líquido ruminal por fístula ou sonda esofágica em bovinos / Effect of rumem cannula and esophageal probe methods on sampling of rumem fluid in cattle

Estudaram-se os efeitos do método de colheita de líquido ruminal, por sonda ou fístula ruminal, e do momento de colheita, antes e depois da alimentaçäo, sobre a concentraçäo e proporçäo de AGVs, concentraçäo de nitrogênio amoniacal, concentraçäo de minerais e pH do líquido ruminal, utilizando-se quatro bovinos machos da raça Nelore, com fístula ruminal e peso médio de 237kg. Observou-se maior concentraçäo total de ácidos graxos voláteis no líquido colhido por fístula antes e depois da alimentaçäo. Maior porcentagem de ácido acético, menor de ácido propiônico e butírico, menor concentraçäo de nitrogênio amoniacal, maior valor do pH e menor concentraçäo de cálcio, de fósforo e de potássio foram obtidas no líquido colhido por sonda esofagiana. Tanto o líquido ruminal colhido por fístula como o por sonda esofagiana antes da alimentaçäo apresentaram menor concentraçäo de AGVs, menor porcentagem de ácido propiônico, menor concentraçäo de nitrogênio amoniacal, maior porcentagem de ácido butírico, maior relaçäo AC/PRO e maior pH do que o colhido após a alimentaçäo. Sugere-se trabalhar com colheitas por fístula ruminal após a administraçäo do alimento em experimentos em que se queira observar os primeiros efeitos dos tratamentos sobre o metabolismo ruminal. Com conhecimento prévio da açäo do tratamento no metabolismo ruminal e sendo utilizado um tratamento-controle, a colheita por sonda esofagiana poderá ser utilizada, mas apenas para experimentos em que os parâmetros ruminais sejam o enfoque secundário.

Influência da dieta aniônica no balanço macromineral em novilhos holandeses / Influence of anionic diet on macromineral balance in holstein steers

O efeito do balanço cátion-aniônico da dieta (BCAD) no balanço macromineral (Ca e P), no pH urinário e fecal, na concentraçäo sérica de cálcio ionizado e total e na ingestäo de matéria seca foi estudado utilizando-se quatro novilhos holandeses machos. Inicialmente os animais foram alimentados com dieta basal com BCAD de +74,12mEq/kg de MS e, posteriormente, com dieta suplementada com sulfato de amônio, de maneira a diminuir o BCAD para -154,84mEq/kg de MS. Näo foram encontradas diferenças (P>0,05) no pH fecal, no balanço de fósforo e na concentraçäo de cálcio ionizado em funçäo do tempo. A urina acidificou-se com a diminuiçäo do BCAD (P<0,01). Para o balanço de cálcio näo foram encontradas diferenças entre tratamentos (P>0,05), entretanto, o cálcio excretado na urina foi maior (P<0,05), com a dieta aniônica. A concentraçäo de cálcio total no soro aumentou significativamente (P<0,05) a partir do 19º dia. Dieta aniônica com uso de sulfato de amônio, em veículo palatável, oferecida na forma de raçäo total, näo interferiu na ingestäo de matéria seca. O pH urinário é excelente indicativo da eficiência da dieta aniônica e foram necessários 19 dias de consumo de uma dieta aniônica de -154,84 mEq/kg de MS para aumentar os níveis séricos de cálcio total em bovinos em crescimento

Coffee Senna (Senna occidentalis) poisoning in cattle in Brazil.

Four 4-5-y-old cows out of a group of 20 developed a toxic myopathy approximately 10 d after being started on a ration contaminated with 21.5% Senna occidentalis beans. Clinical signs included progressive muscle weakness, incoordination of hindlimbs, reluctance to move, dragging of the tip of the hooves of the hindlimbs, and sternal and lateral recumbency. Gross lesions included white to whitish-yellow discolored areas of several groups of skeletal muscle in various regions of the body, but more markedly in the hindlimbs. Significant histopathological changes were restricted to skeletal muscles with variable degrees of segmental degenerative myopathy associated with reparative events. The earliest change seen at electron microscopy of affected skeletal muscles was mitochondrial swelling. More advanced changes ranged from disruption of sarcoplasm and myofibrils to complete lysis of a myofiber segment and early regeneration. Myocardial fibers had swollen mitochondria, disruption of cristae and dense matrical globules. The epidemiology, clinical data and gross, histopathological, and ultrastructural features of S occidentalis poisoning in cattle are presented.

Ionophore antibiotic (narasin) poisoning in rabbits.

Outbreaks of narasin poisoning in rabbits from several commercial rabbit-raising farms in the state of Parana, Brazil, are reported. Approximately 5,000/35,000 rabbits died after having consumed a pelleted ration to which poultry ration premix had been added. Clinical signs included apathy, anorexia, muscle weakness, impaired walking, diarrhea, respiratory distress, and opistothonus. Gross findings were not remarkable, but varying degrees of degeneration, necrosis and regeneration of skeletal muscles were consistent histopathological features in affected rabbits. Myocardial changes were mild or absent. Thirty ppm of narasin were detected in the ration fed the rabbits. The disease was experimentally reproduced by feeding the suspected ration and by administering narasin po to rabbits.

Behavioral effect of selective and non-selective lesions of median raphe nucleus in the rat.

The role of the serotonergic (5-HT) system in the regulation of locomotor activity and consummatory behaviors was studied. Electrolytic and chemical (5,7-dihydroxytryptamine: 5,7-DHT) lesions were made in the median raphe nucleus (MR). The effects of these lesions on spontaneous locomotor activity, food and water intake and body weight were then studied. In these experiments, rats on an ad libitum feeding-drinking regimen were housed individually in cages with activity wheels located in a room kept at a temperature of 22 + 1 degrees C. For each rat, records were kept of its spontaneous locomotor activity, food and water intake, and body weight for 8 weeks before and after the placement of lesion in MR. It was observed that: (1) electrolytic destruction of the MR produced a permanent decrease in locomotor activity, and (2) there were a reduced food intake and a decreased spontaneous activity after intra-MR injection of 5,7-DHT.

Effects of damage to median raphe nucleus on ingestive behavior and wheel running activity.

The effects of damage to the median raphe nucleus on the ingestive behavior and wheel running activity of rats were studied. This nucleus was damaged by the placement of either electrolytic or chemical (5,7-dihydroxytryptamine) lesions. After the placement of either type of lesion, wheel running activity was significantly decreased for the duration of the 8 week post-operative period. Although there were transient decreases in both food and water intakes after damage to the median raphe nucleus, these decreases did not appear to result from impairments in neuro-regulatory mechanisms. Rather, the decrease in food intake seemed to be related to the decrease in locomotor activity, and the decrease in water intake appeared to be linked to the decrease in food intake. In some rats with electrolytic lesions in the median raphe nucleus, the decrease in water intake was followed by a transient period of hyperdipsia.