6 research outputs found

    Resposta diferencial de cultivares de algodão ao manganês em solução nutritiva

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    Manganese toxicity may be a major constraint to cotton production in the states of São Paulo and Paraná and Mn deficiency may be a problem in the cerrado areas of Brazil. The objective of this experiment was to study the differential response of three cotton cultivars to Mn in nutrient solution. Cotton plants of the cultivars Coodetec 401, CNPA-ITM 90 and IAC 22 were grown in pots with nutrient solutions containing 0.0, 36.4, 72.8, 145.5 and 290.9 mmol L-1 of Mn for 70 days after emergence. Deficiency symptoms were noticed only in the Mn-free treatment in all of the three cultivars. There was an effect of Mn deficiency in the nutrient solution decreasing plant height, dry matter production, Mn accumulation and the retention of reproductive structures. There was no visual symptoms of Mn toxicity in any of the cotton cultivars, despite the high levels of Mn in the leaves. There was no difference in Mn accumulation among the three cotton cultivars, but IAC 22 was more sensitive to Mn toxicity and Coodetec 401 and CNPA-ITM 90 were more sensitive to Mn deficiency.Both Mn deficiency and toxicity may lead to decreased cotton production with no visual symptoms.Enquanto a toxidez de Mn pode ser um problema para a cultura do algodoeiro nos estados de São Paulo e Paraná, a deficiência pode causar problemas nas áreas de solos sob cerrado. No presente trabalho, objetivou-se o estudo da resposta comparativa de cultivares de algodão ao Mn, em solução nutritiva. Plantas de algodão dos cultivares Coodetec 401, CNPA-ITM 90 e IAC 22 foram cultivadas em vasos, com solução nutritiva que continha 0,0, 36,4, 72,8, 145,5 e 290,9 ∝mol L-1 de Mn, por 70 dias. Foi observado sintoma de deficiência de Mn apenas no tratamento sem Mn, para os três cultivares. A deficiência de Mn na solução nutritiva provocou a diminuição da altura das plantas, produção de matéria seca, absorção de Mn e retenção de estruturas reprodutivas. Não foram notados sintomas visuais de toxidez de Mn em qualquer dos três cultivares, mesmo com teores muito altos do nutriente nas folhas. Embora os três cultivares não apresentem diferenças quanto à absorção total de Mn, IAC 22 é mais sensível à toxidez, enquanto Coodetec 401 e CNPA-ITM 90 são mais sensíveis à deficiência do nutriente. Pode haver prejuízo na fixação de estruturas reprodutivas, tanto com deficiência como com toxidez de Mn, sem sintomas aparentes.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Different Nutritional Systems at Suckling and Finishing Phases of Lambs Grazing on Tropical Pasture

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    The objective of the study was to evaluate the lambs' performance in the suckling and finishing phases in different nutritional systems. The study was carried out in two phases: suckling (from birth to weaning) and finishing (from weaning to slaughter). Each phase was evaluated in two experimental periods (characterized by year). The suckling phase used 76 lambs divided into two groups: control (without supplementation) and creep feeding (with creep feeder supplementation of 20 g/kg of body weight). The lambs were distributed in the treatments according to sex and type of delivery (single or twin). The finishing phase was characterized from weaning to slaughter. Sixty-two lambs were used, 28 females and 34 males, average age of 85 days and an average weight of 19 kg, and the animals were distributed in treatments according to weight and sex. Five treatments were evaluated, animals in Brachiaria spp. receiving increasing levels of supplementation (0%, 0.8%, 1.6%, and 2.4% of BW) and confinement as a positive performance control. The creep feeding treatment presented superior performance with an average daily gain of 64.85 g more than the control treatment, which anticipated the shorter age at weaning with higher weaning weight (weaning in 64 days for supplemented lambs and 77 days for animals without supplementation). In the finishing phases, the lambs of the treatments 1.6%BW and 2.4%BW presented average daily gain similar to the confined animals and higher (p<0.05) than the treatments 0.8%BW and 0%BW. We recommend that ad libitum supplementation of creep feeding during the suckling phase is a nutritional strategy to wean heavier lambs and consequently reduce time in the finishing phase. For fattening the lambs, we recommend the inclusion of protein-energy supplementation of 1.6% BW for lambs produced in the tropical pasture

    Productive and Reproductive Efficiency of Ewes Kept on Tropical Pastures as a Function of the Suckling Lamb Treatments

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    The aim of the research was to evaluate the productive and reproductive performances of ewes as a function of the supplementation offered to suckling lambs. The lambs were divided into two experimental treatments. Treatment (1) suckling lambs kept in pastures of Brachiaria-grass receiving mineral supplementation; and treatment (2) suckling lambs kept in pastures of Brachiaria-grass receiving concentrate supplementation in creep-feeding. Regardless of the nutritional treatment offered to the lambs, all matrices (female lambs and ewes) received 350 g of supplementation daily. Ewes from treatment-1 presented average 49 days to return to estrus. Ewes from treatment-2 presented, on average, 36 days to return to estrus. The body condition score (BCS) at weaning showed a significant difference between treatments. Ewes from treatment-1 presented a mean BCS of 1.75. Ewes from treatment-2 presented a mean BCS of 2.39. The other productive variables of lambs, such as weaning weight (kg), age at weaning (days), total weight gain (kg), and average daily gain of lambs, presented a significant difference between the nutritional treatments. Variables such as return to estrus and BCS were positively influenced by supplementation offered to lambs, which directly impacts the production efficiency and profitability of the production system. The lamb supplementation promotes indirect gains in the body condition score of ewes at weaning and, consequently, in the time to return of estrus in 13 days. Protein-energy supplementation in creep feeding to suckling lambs is recommended to improve the body condition score at weaning and decrease the return to estrus (days) of ewes. This nutritional tool is recommended to improve the supply of leaves and provide the best conditions for the selection and use of nutrients present in the leaves

    Performance, ingestive behavior and gastrointestinal helminths control of suckling lambs supplemented in creep-fed and not supplemented in tropical pastures.

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    Abstract: The objective of this study was to evaluate the performance, ingestive behavior and gastrointestinal helminths control of suckling lambs raised on pastures of Brachiaria ssp. supplemented in creep-fed and not supplemented. Thirty-one lambs being 15 lambs in the control treatment (without supplementation) and 16 lambs in the creep feeding treatment (with protein-energetic supplementation) were evaluated. Performance of lambs supplemented was superior to lambs no-supplemented. Lambs without supplemented had weaning age of 81 days and an average gain of 194 grams. Lambs supplemented showed weaning age of 58 days and average daily gain of 268 grams. eggs per gram of stool (EPG) count in the control treatment was 4553, while in the creep feeding treatment the mean was 763. The morbidity rate caused by gastrointestinal helminths in the control treatment was 6.6% and there was no morbidity due to helminths in the treatment creep feeding. The morbidity rate due to hepatogenic intoxication was 46.6% in control and 12.5% in the lambs supplemented. The ingestion of protein-energy supplementation in creep feeding promoted an increase in productive performance of lambs, as well as increased resistance and tolerance to gastrointestinal infections and decreased cases of hepatogenic intoxication by ingestion of Brachiaria spp.Made available in DSpace on 2019-10-08T00:34:12Z (GMT). No. of bitstreams: 1 CNPC2019PerformanceIngestive.pdf: 400693 bytes, checksum: 9596755a4344b7b51fada54538a12cf4 (MD5) Previous issue date: 2019bitstream/item/202661/1/CNPC-2019-Performance-Ingestive.pd

    Strategic alliance-based sourcing and market performance: evidence from foreign firms operating in China

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    Although foreign multinational firms from the Triad regions increasingly use mainland China as both a sourcing and a marketing location, no study has directly examined the sourcing strategy–performance linkage. Using resource complementarity and resource dependence theory, we extend the sourcing literature and apply these perspectives to an important transitional economy—China. These two theoretical perspectives suggest that product and uncertainty factors moderate the relationship between strategic alliance-based sourcing (SA sourcing) of major components and market performance. We find that, at low levels of product innovativeness and technological uncertainty, the use of SA sourcing is positively related to market performance. However, the effects of product differentiation and demand uncertainty on the sourcing–performance relationship are insignificant. Journal of International Business Studies (2005) 36, 187–208. doi:10.1057/palgrave.jibs.8400120
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