RESUMO -O trabalho foi realizado com o objetivo de avaliar as curvas de lactação de vacas Nelore e mestiças F1 LimousinNelore (LN) e Simental-Nelore (SN) e o desempenho de suas progênies. Foram utilizadas 13 vacas de cada grupo genético, com 5 a 9 anos de idade, e as suas respectivas crias. A partir do 15 o dia após o parto até a desmama dos bezerros (210 dias), as vacas foram mantidas com suas crias em baias individuais. No arraçoamento procurou-se atender 100% das exigências de mantença e lactação das vacas; a mesma ração foi fornecida aos bezerros a partir dos 90 dias de idade visando atender no máximo 30% de suas exigências nutricionais. A ração foi formulada com 30% de concentrado e 70% de silagem, na MS. A produção de leite das vacas foi determinada mensalmente pelo método da diferença de peso dos bezerros. Por meio de um modelo não-linear, estimaram-se o tempo necessário para as vacas atingirem o pico de lactação, a produção no pico, a persistência de produção de leite e as produções total e média diária. As vacas Nelore tiveram, em comparação às mestiças, menores produções no pico de lactação, total e média diária, mas apresentaram maior persistência de lactação. As produções no pico de lactação, total e média diária, nas vacas SN foram maiores que nas vacas LN, no entanto, não houve diferença entre esses grupos quanto à persistência de lactação. Os bezerros das vacas Nelore apresentaram menores ao nascer e à desmama e ganharam menos peso no período de aleitamento em comparação aos de vacas mestiças, que não diferiram entre si. Vacas mestiças têm maior habilidade materna que vacas Nelore.Palavras-chave: curva de lactação, Limousin, Simental Milk production and performance of calves from Nellore and crossbred cowsABSTRACT -The research was carried out to evaluate the lactation curves of Nellore and Crossbred F1 Limousin-Nellore (LN) and Simmental-Nellore (SN) cows and the performance of the progeny. Thirteen cows from each breed group, with age ranging from 5 to 9 years, and the respective calves were used. From 15 days after calving until weaning of the calves (210 days), the cows and calves were kept in individual pens. The nutritional requirements of the cows for maintenance and lactation were met. The same ration was offered to the calves from the 90 days of age, in limited amounts to supply 30% of the nutritional requirements. The ration was formulated with 30% of concentrate and 70% of silage, DM basis. Monthly, milk production of the cows was estimated, utilizing the weigh-suckle-weigh method. By means of nonlinear model, it was estimated the time needed for the cows to reach the peak of lactation, the production at the peak of lactation; the persistence of milk production and total and daily average milk production. Nellore cows showed lower production at the peak of lactation, total and daily average milk production, but higher persistency than crossbred cows. The productions in the lactation peak, total and daily average, in cows SN, were higher than in cows LN, however, no difference was observ...

We evaluated the fermentation products, the gaseous and effluent losses of sugarcane silages without calcium oxide (CaO) or with CaO addition, at the levels of zero, 0.8%, 1.6% and 2.4%, in association with the microbial additive Lactobacillus buchneri inoculated at the levels of zero, 50.000, 100.000 e 150.000 ufc/g of sugarcane, wet bases. The variety RB855536, harvested after 12 months of first growth was used. The experiment design was the completely randomized design, in a 4 × 4 factorial arrangement. They were evaluated in the silages, the contents of volatile fatty acids, lactic acid, ethanol, and the pH, as well as the gaseous and effluent losses. In the analysis of the data, the SAS system was utilized. It was observed on interaction effect of the chemical and microbial additive over the contents of lactic acid, acetic acid, propionic acid, butyric acid, ethanol and over the gaseous and effluents losses. However, there was no interaction effect regarding to pH. When it was observed on interaction effect of additives, the effects of the levels of one additive were evaluated by regression analysis in each level of each other, and vice-versa. The level 1.6% of CaO associated to the level 50,000 ufc/g of natural matter of Lactobacillus buchneri provided adequate levels of lactic acid (superior to 4.5%), and of acetic acid (around 1%), mod-F. T. de Pádua et al. 637erate content of propionic acid (0.55%), low content of butyric acid (0.05%) and controlled the production of ethanol and the gaseous and effluent losses. The pH of the silages were influenced by CaO addition, but were not affected consistently by microbial inoculation.

RESUMO -Objetivou-se avaliar a eficiência de conversão da matéria seca (MS) e da energia metabolizável (EM) da dieta em ganho de peso e em peso de bezerro desmamado por vaca. Utilizaram-se 13 vacas Nelore, 13 mestiças F1 Simental × Nelore (SN) e 13 F1 Limousin × Nelore (LN) com 5 a 9 anos de idade e suas respectivas crias. Entre 15 e 210 dias pós-parto, as vacas foram mantidas em baias individuais, juntamente com os bezerros. Utilizaram-se rações contendo, na MS, 30% de concentrado e 70% das silagens de milho e sorgo na primeira e segunda metades do período experimental, respectivamente. O conteúdo de energia metabolizável das dietas foi obtido utilizando-se o fator 0,82 na conversão da energia digestível, determinada experimentalmente, em energia metabolizável. A produção de leite foi determinada mensalmente utilizando-se o método da diferença de peso dos bezerros.A eficiência foi avaliada considerando as relações: kg de bezerro desmamado e kg de ganho de peso de bezerro por kg de MS; ou porMcal de EM ingeridos pela vaca; ou pelo par vaca/bezerro no período de lactação: ou foram estimadas para todo o ano. Foi ainda considerada a relação peso do bezerro/peso da vaca (PB/PV) à desmama. As vacas mestiças apresentaram maior eficiência de conversão da MS e da energia alimentar em peso de bezerro desmamado e em ganho de peso de bezerro. Apresentaram ainda as mais elevadas relações PB/PV à desmama. Os dois grupos de mestiças não diferiram quanto à eficiência. A utilização de matrizes obtidas por cruzamento entre bovinos de raças européias e bovinos Nelore possibilita elevar a eficiência do sistema na fase de cria.Palavras-chave: conversão da energia, conversão da matéria seca, Limousin, Simental Efficiency of conversion of feed energy for the production of calves byNellore and crossbred cows ABSTRACT -The objective was to evaluate the efficiency of conversion of dry matter (DM) and metabolizable energy (ME) of the diet on weight gain and weight of calf weaned per cow. A total of 13 Nellore, 13 crossbred F 1 Simental × Nellore (SN) and 13 F1 Limousin × Nellore (LN) cows with 5 to 9 years of age and their offspring was used. Between 15 and 210 days post calving, the cows were kept in individual stalls, with the calves. Diets contained 30:70% (% DM) concentrate to corn or sorghum silages ratio, in the first and second half of the experimental period, respectively. The metabolizable energy content of the diet was obtained using the 0.82 factor in the conversion of digestible energy, experimentally determined, in metabolizable energy. The milk production was determined monthly using the calf weigh-suckle-weigh method. The efficiency was evaluated considering the ratios: kg of calf weaned and kg weight gain of calf per kg DM, or by Mcal of EM consumed by the cow, or by cow/calf pair in the period of lactation or were estimated for all the year. The relationship of calf weight/weight of the cow (CP/LW) at weaning was also considered. The crossbred cows showed higher efficiency of conversion of the DM and the feed energy in w...

This paper presents the activities currently being performed at the Inmetro with a view to obtaining the international recognition of its quantum Hall system as the primary standard of electrical resistance in Brazil. To enable it, the Inmetro is making arrangements to take part in the ongoing key comparison BIPM.EM-K12, which is an on-site comparison of quantum Hall effect resistance standards. Besides, as a prerequisite for joining in this key comparison, Inmetro is participating in the ongoing key comparison BIPM.EM-K13.a&b.

In September 1997, after the tropical winter season and following a long warm (28 to 33°C) and rainy (27 mm) period, smut symptoms were observed on two dry-bean (Phaseolus vulgaris) fields in Brazil. Brownish to blackish powdery masses of spores were observed on stems, pods, and roof green and senescent plants. No galls were observed. Hyphae in infected tissue were intercellular; no clamp connections were observed. Typical globose teliospores were observed that measured 7 to 11 μm. Spores were uninucleate or binucleate; predominantly brownish with flattened poles and equatorial band; the exospore wall was thick and surface ornamented (echinulate-type). Teliospores incubated in water drops generated transversely septate promycelia, unbranched, producing terminal and lateral basidiospores. The fungus did not grow well on potato dextrose agar (PDA) medium, generating yeastlike colonies. To confirm pathogenicity of a Ustilago sp., spores collected from field-infected plants were inoculated on 8- and 20-day old seedlings of dry-bean cultivars Rosinha and Perola. Spore suspensions of 105 teliospores were sprayed all over the plants. After inoculation, plants were kept in a moist chamber (relative humidity [RH] 100%) for 2 days. At the third day, inoculated plants were covered with clear polyethylene bags and transferred to the greenhouse (RH 50%, temperature 25 ± 2°C). Noninoculated controls were included for comparisons. Within 2 weeks, all inoculated plants reproduced field symptoms of darkened tissues covered by profuse sori containing teliospores and basidiospores. Eight-day-old plants died 2 weeks after inoculation. Noninoculated plants did not develop any symptoms. Teliospores obtained from dead plants were identical to those used for inoculation, thus completing Koch's postulates. Fischer (1), and later Fischer and Shaw (2), proposed a species concept for Ustilago based on morphology (primarily of the teliospore), symptomatology, and host specialization at the host-family level. Although the teliospores found on dry-beans, in Brazil, are much like those of Ustilago maydis, the fungus did not cause galls on plants, was able to infect roots and kill seedlings. and is very well adapted to a legume plant. Cross inoculation tests indicated that spores from dry-beans cannot cause disease symptoms on maize. We therefore regard the bean smut as a new species. We are not aware of any other Ustilago sp. being reported on a legume host. References: (1) G. W. Fischer. 1953. Manual of the North America Smut Fungi. (2) G. W. Fischer and C. G. Shaw. Phytopathology 43:181, 1953.