ABSTRACT The Jatropha curcas species is a perennial plant and easy to manage, being cultivated in many countries because of its high content in oil and the lowest cost of production. This study had as objective to evaluate the injuries caused by the Pachycoris torridus in J. curcas seedlings. Thirty-four days after the planting, 30 J. curcas seedlings were covered with screens and submitted to herbivory of five bugs of the same sex. Morphological and physiological evaluations were conducted 65 days after planting. Seventy-three days after planting, 24 seedlings were submitted to herbivory, using the same methodology as the previous experiment with a quantitative differential of 10 bugs and a batch of 6 plants without insects (control). Evaluations were done 104 days after planting. Male adults (n = 5) of the P. torridus species caused a reduction in the growth and biomass increase in J. curcas seedlings 34 days after planting. After 30 days of herbivores, however the same injuries were not observed in seedlings with 73 days after planting. The injuries (34 days after planting) were considered mild and there was a decrease in the growth and in the biomass accumulation. Upon reaching 73 days after planting, the seedlings became more resistant to the attack of this pest, in such a way that as submitting them to twice the number of insects (n = 10), they did not negatively responded to the herbivory. Finally, the young seedlings were more susceptible to attack, even with low levels of infestation. The pest control should be done when there are signs of infestation at this stage.

Objetivou-se estimar os efeitos da substituição do farelo de soja por levedura seca de cana-de-açúcar sobre as características da carcaça e não carcaça de cordeiros terminados em confinamento. Foram avaliados quatro tratamentos (0,0; 33,0; 66,0 e 100,0%) que consistiam de níveis de inclusão de levedura seca em substituição ao farelo de soja, num delineamento experimental de blocos inteiramente casualizados, com nove repetições. A substituição do farelo de soja por levedura seca diminuiu linearmente os não constituintes da carcaça, consumo de matéria seca, ganho de peso diário, peso corporal ao abate, conformação, grau de acabamento das carcaças, rendimento de carcaça e cortes cárneos. A inclusão de levedura não interferiu nas características cor do Longíssimus dorsie gordura renal, enquanto para área de olho de lombo, gordura pélvica renal e escore corporal, ao passo que se incluía levedura seca houve diminuição dessas variáveis. A margem bruta por cordeiro diminuiu à medida que se incluiu a levedura seca nas dietas. A substituição do farelo de soja por levedura seca de cana-de-açúcar afeta negativamente as características da carcaça e não carcaça dos cordeiros.

The objective was estimate the effects of replacing soybean meal by dry yeast sugarcane on carcass characteristics and non-carcass of lambs finished in feedlot. We evaluated four treatments (0.0, 33.0, 66.0 and 100.0%) consisting of sugar cane dry yeast inclusion levels to replace soybean meal in an experimental randomized complete block design with nine repetitions. The replacement of soybean meal by sugar cane dry yeast decreased linearly constituents non-carcass, dry matter intake, daily weight gain, body weight at slaughter, conformation, degree of completion of the carcasses, carcass yield and meat cuts. The inclusion of sugar cane dry yeast did not affect the color of thelongissimus dorsi and kidney fat, while for rib eye area, renal pelvic fat and body condition, whereas if included sugar cane dry yeast there was a decrease of these variables. Gross margin decreased by lamb as it included the sugar cane dry yeast in the diet. The replacement of soybean meal by sugar cane dry yeast sugarcane negatively affects carcass and non-carcasscharacteristics of lambs.

Avaliou-se o efeito de níveis de suplementação no desempenho de novilhos de três grupos genéticos (Nelore x Red Angus (NR), Nelore (NL) e mestiço Holandês (MH)), em três períodos experimentais. O desempenho do primeiro período foi analisado em DBC, composto por três tratamentos (NR, NL e MH) e três blocos. No segundo período, usou-se DBC em esquema de análise fatorial 3 x 3, com três blocos. O fator A determinou o grupo (NR, NL e MH) e o fator B, níveis de suplementação (0,2; 0,6 e 1% PV). No terceiro período, usou-se DIC em esquema de análise fatorial 2 x 3. O fator A determinou o grupo (NL e MH) e o fator B, três níveis de suplementação. No início, foi verificado maior ganho de peso (GP) no NR (0,79 kg dia-1) comparado ao MH e N (0,73 e 0,61 kg dia-1). O consumo de concentrado variou no NL. No segundo período, o NR apresentou maior GP (0,91 kg dia-1) comparado ao NL (0,75 kg dia-1) e MH (0,76 kg dia-1), sendo influenciados pelos níveis de suplementação. No terceiro período, MH apresentou maior GP (0,89 kg dia-1). Não houve diferença entre os animais com 0,8 e 1,2% do PV, com GP de 0,82 e 0,92 kg dia-1.

This trial was carried out to study the effects of supplementation level on performance of steers from different genetic groups (Nellore x Red Angus (NR), Nellore (NL) and Holstein crossbred (MH), and three experimental periods. The performance data for first period were analyzed according to randomized block (RB) design, with 3 treatments ((NR, NL and MH)) and 3 blocks. In second period, the RB design used with 3 x 3 factorial design, and 3 blocks. Factor A determined the group (NL and MH) and factor B the supplementation levels (0.2, 0.6 and 1% LW). In third period, the data were evaluated according to completely randomized design, with 2 x 3 factorial design. Factor A determined the group and factor B, three levels of supplementation. In the first, higher weight gain (p < 0.05) was observed for NR (0.79 kg day-1) compared to MH and NL (0.73 and 0.61 kg day-1). The concentrate intake varied for N. NR showed higher (p < 0.05) WG (0.91 kg day-1) compared to NL (0.75 kg day-1) and MH (0.76 kg day-1). The levels of supplements influenced (p < 0.05) WG (0.68, 0.81 and 0.92 referring to levels of 0.2, 0.6 and 1.0% LW). In third period, MH presented greater WG < 0.05) (0.895 kg day-1). No difference was verified on animals with 0.8 and 1.2% LW, with WG of 0.92 and 0.82 kg day-1.

O objetivo do presente trabalho foi avaliar a concentração de N-NH3, o pH do líquido ruminal e a eficiência de síntese microbiana de rações que continham diferentes fontes energéticas: milho (MI), milho + casca de mandioca desidratada (MC), raspa de mandioca (RM) e farinha de varredura de mandioca (FV). Foram utilizados quatro novilhos da raça Holandesa (270 kg), portadores de cânulas ruminal e duodenal, distribuídos em um delineamento Quadrado Latino 4x4. A cinza insolúvel em ácido foi utilizada como indicador do fluxo duodenal e fecal. Não houve efeito das rações experimentais no pH ruminal. No entanto, menor concentração de N-NH3 foi observada para a ração com FV. O fluxo duodenal de matéria orgânica e nitrogênio e a composição química das bactérias ruminais não foram influenciados pelas rações experimentais. A maior eficiência microbiana aparente foi obtida para a ração com FV. Nas condições do presente experimento a FV, possivelmente apresentou uma melhor sincronização com a fonte protéica (farelo de soja), diminuindo a perda de nitrogênio na forma de N-NH3 e aumentando a eficiência microbiana.

The objective of this paper was evaluate ammonia concentration, pH of ruminal liquid and microbial synthesis efficiency in diets with different energetic sources: corn (CO), corn/cassava hulls (CC), cassava root (CR) and cassava by-product flour (CB). Four Holstein steers (270 kg) were used, in a 4 X 4 Latin Square design. The marker utilized for determination of duodenal and fecal flow was the acid insoluble ash. There was not effect in the ruminal pH of the experimental diets, however smaller ammonia concentration was observed to the diet with CB. The organic matter and nitrogen flow to duodenum and chemical composition of ruminal bacteria were not influenced by experimental diets. The higher apparent microbial efficiency was obtained to CB diet. In the conditions of the present experiment the CB possibly presented better synchronization with the protein source (soybean meal), decreasing the loss of nitrogen under N-NH3 form and increasing the microbial efficiency.

Avaliaram-se as digestibilidades parcial e total de rações combinando fontes de amido (AM) de alta (casca de mandioca desidratada) e baixa (milho) degradabilidade ruminal, com fontes de nitrogênio (N) de alta (levedura) e baixa (farelo de algodão + farinha de carne e ossos) degradabilidade ruminal, em arranjo fatorial 2x2. Foram utilizados quatro novilhos da raça Holandesa (334 kg), portadores de cânula ruminal e duodenal, distribuídos em delineamento quadrado latino 4x4. O óxido crômico foi utilizado como indicador de fluxo de matéria seca. Houve interação das fontes de AM e N sobre o coeficiente de digestibilidade aparente (CDA) da proteína bruta (PB) e fibra em detergente neutro (FDN). As rações com milho e levedura e as com casca de mandioca e farelo de algodão + farinha de carne e ossos apresentaram maior CDA para PB do que as rações com milho e farelo de algodão + farinha de carne e osso e com as casca de mandioca e levedura. A ração com amido e N de alta degradabilidade ruminal (casca de mandioca e levedura) propiciou menor valor sobre o CDA da FDN do que as demais rações, que não diferiram entre si. A digestão ruminal da FDN foi maior quando a fonte de AM foi o milho, comparada àquela contendo casca de mandioca. A maior digestão do AM foi para as rações com casca de mandioca, comparada às rações com milho, em todos os segmentos do trato digestivo. Observaram-se valores negativos para a digestão ruminal da PB para as rações experimentais. A fonte de N influenciou a digestão ruminal e intestinal da energia bruta. A maior a digestão ruminal ocorreu nas rações com levedura e a maior digestão intestinal, nas rações com farelo de algodão + farinha de carne e ossos.

Total and partial digestibility of diets combining the starch sources of high degradability (dried cassava hulls) and low degradability (corn), with nitrogen sources of high (yeast) and low (cottonseed meal and meat and bone meal) degradability, in a 2 x 2 factorial arrangement, were evaluated. Four Holstein steers (334 kg) fitted with ruminal and duodenal cannulas, in a 4 x 4 Latin Square were used. Chromic oxide was used as a marker for drying matter flow. Interactions of starch and N sources on apparent digestibility coefficient (ADC) of crude protein (CP) and neutral detergent fiber (NDF) was detected. Diets of corn and yeast, cassava hulls and cottonseed meal + meat and bone meal showed higher ADC of CP than diets of corn and meat and bone meal and with cassava hulls and yeast. The diet of starch and N with high ruminal degradability showed lower value than others diets, that was not different. Ruminal digestion of NDF was higher when starch source was corn compared with cassava hulls. The highest digestion of starch was higher in diets with cassava hulls than in diets of corn, in all segments of digestive system. Negative values for ruminal digestion of CP to experimental diets were observed. The N source influenced ruminal and intestinal digestion of energy. The ruminal digestion was higher in diets with yeast e intestinal digestion was higher in diets with cottonseed meal + meat and bone meal.