Adubação nitrogenada na cultura do milho com ureia revestida por diferentes fontes de polímeros

In view of theoretic increase in efficiency of nitrogen fertilizers for controlled release, this study aimed to evaluate the effect of nitrogen, using conventional urea and ureas coated by different polymers, in the leaf N content, leaf chlorophyll index, components production and grain yield of irrigated corn in growing season and second crop in the savannah region. The experiments were conducted at experimental area belonging to UNESP - Ilha Solteira, located in Selviria - MS in a dystrophic Red Latosol (Haplustox), clayey texture. The statistical design was randomized blocks, with four repetitions, in a 4 x 4 factorial arrangement, being four nitrogen doses (0, 40, 80 and 120 kg ha(-1)) applied at sidedressing and four urea sources (a conventional urea and three coated with polymers in different compositions and concentrations). The coated ureas are not efficient under the soil and climate conditions studied of the savanna, because they provided results similar to the conventional urea for the production components and grain yield of corn in the first and second crop. The increment of nitrogen doses increase linearly the leaf N content and grain yield of corn in the first and second crop.

Mineralização de nitrogênio do esterco bovino e produção de alface em função de N-ureia

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Suplementação com gordura protegida para vacas de corte desmamadas precocemente mantidas em pastagem natural

The objective of this work was to evaluate the productive and reproductive performance of beef cows, as well as the performance of their calves according to the following dietary treatments: PRE: supplemented with protected fat (PF) during 45 days prepartum; PREPOS: supplemented with PF during 45 days prepartum and 63 days postpartum; POS: supplemented with PF during 63 days postpartum; PN: without supplementation. The productive performance of cows was not influenced by feed management (P>0.05), except for body condition score (BCS), which was lower for PRE and PREPOS cows at the end of mating season, with the latter cows having similar BCS POS and PN. The calving interval (CI) was shorter for cows supplemented in PREPOS - 376 days -, and did not differ in cows maintained in PN - 383 days. Supplemented PREPOS cows weaned 4.4% more pounds of calf per 100kg of cow at calving - 22.6kg - than the PRE and POS cows - 21.6kg and 21.6kg, respectively - and 8,4% more pounds of calf per 100 of cow at calving than the cows maintained in native pasture - 20.7kg. The fat protected supplementation during pre and/or postpartum periods did not affect the performance of cows and calves.

Correlações entre padrões hematológicos, parasitológicos e desempenho animal de ovelhas suplementadas com gordura protegida

The development of populations of gastrointestinal parasites resistant to antihelmintics has led to seeks new alternatives its control. Stimulation of natural immunity by means of animal nutrition has shown promising results in controlling nematodes in sheep. The addition of protected fat sources, containing essential fatty acids, may be an alternative due to many effects, among them, regulation of immunity expression and regulation of the inflammatory response by immune effectors. The aim of this study was to estimate correlations between haematological and parasitological patterns, animal performance through weight and body condition, under the influence of protected fat in ewes. Fifty Santa Ines sheep, in the final third of pregnancy or postpartum, in paddocks of Panicum maximum, received, individually, 200 g per day of concentrate, isonitrogenous and isocaloric diets, with or without the addition of protected fat. In general, except for total leukocytes and eosinophils, almost all of Pearson correlation coefficients of other variables were significant. However, the protected fat, in the amount offered, had no antihelmintic effect.