29 research outputs found
Effect of chronic infusion of leptin and nutrition on sexual maturation of zebu heifers
The amount of fat in the carcass has been proposed as a regulator of initiation of puberty in cattle. To test if changes in energy intake and in circulating leptin concentration are each capable of altering age, BW, and body composition at puberty, 36 prepubertal Nellore heifers, 18 to 20 mo old, 275.8 ± 17.2kg BW, and BCS of 5 ± 0.5 (1 to 9 scale), were randomly assigned to each of 3 treatments (n = 12): High (high energy diet), Low (low energy diet), and LL [low energy diet + ovine leptin (oLeptin)]. Diets were formulated to promote BW gain of 0.4 kg/d (groups Low and LL) or 1.2 kg/d (High group). After 14 d of adjustment to diet, heifers in LL group received subcutaneous injections of oLeptin at 4.8 μg/kg BW twice a day for 56 d. Groups High and Low received similar injections of 2 mL saline solution. Age at puberty was considered to be the age on first detection of a corpus luteum, confirmed by plasma concentrations of progesterone of >1 ng/mL. Heifers were slaughtered on the second day after first corpus luteum detection. Expression of leptin gene was quantified by real-time PCR using ribosomal protein-L19 (RPL19) as a control gene. Leptin administration increased (P = 0.04) leptin serum concentration but had no effect (P > 0.05) on age, BW, or BCS at puberty. High energy intake increased (P < 0.01) leptin concentration, accelerated (P = 0.02) puberty, and increased (P < 0.01) BCS at puberty, without altering (P = 0.17) BW at puberty. High energy intake also accelerated (P = 0.04) follicular development. Leptin administration caused a significant (P < 0.05) but transient increase in follicular development, which was similar to the transient increase in leptin serum concentration. Results from leptin gene expression demonstrated that high energy intake increased (P < 0.01) and leptin administration decreased (P < 0.01) leptin expression in 3 adipose tissues. The observed decrease in leptin gene expression after administration of leptin could explain the reduction in leptin serum concentration after 30 d of treatment and consequently the failure of leptin to accelerate puberty. Our findings did not support the hypothesis that reduced serum concentration of leptin is an important hindrance for puberty onset in malnourished zebu heifers. Although exogenous administration of leptin temporarily enhanced rate of follicular growth, it did not accelerate puberty
Caracterização do Queijo Artesanal de Alagoa - MG: parâmetros fÃsicos, fÃsicoquÃmicos, microbiológicos e sensoriais.
Resumo ? O conhecimento do processo de produção do leite e fabricação do queijo é fundamental para padronização e qualidade do queijo artesanal. Com este objetivo, utilizando entrevistas estruturadas, foram identificadas as variáveis que compõem o sistema de produção de leite e as etapas do processo de fabricação do queijo artesanal de Alagoa-MG. Os parâmetros fÃsicos (diâmetro e altura), fÃsico-quÃmicos (umidade, matéria gorda no extrato seco, proteÃna e cloretos) e sensoriais foram pesquisados nos queijos de seis produtores com 14 dias de maturação. A pesquisa de L. monocytogenes e Salmonella spp. e a contagem de Staphylococcus coagulase positiva (SCP) e coliformes foi realizada no leite cru, assim como no queijo recém-fabricado e após sete, 14, 21 e 28 dias de maturação dos mesmos seis produtores do municÃpio de Alagoa. A produção de leite no municÃpio de Alagoa se caracteriza por um sistema semiextensivo com suplementação no cocho durante todo o ano. A área de 90% das propriedades é inferior a 30 ha, sendo 2/3 destas áreas constituÃdas de pastagens [Urochloa (Brachiaria) decumbens cv. Basilisk] manejadas sem adubação. Os rebanhos são constituÃdos, na sua maioria, por vacas Girolando ou mestiças (58%), sendo que 42% das vacas em lactação produzem entre 11 e 15 litros leite/dia. Em 2015 90% das queijeiras produziram até 14.000 kg de queijo. As análises microbiológicas revelaram a presença de SCP e de coliformes totais e termotolerantes no leite cru e nos queijos, em contagens acima do limite máximo estabelecido pela legislação em algumas propriedades. O número total desses microrganismos apresentou uma tendência de queda com o decorrer da maturação do queijo. As análises da composição dos queijos indicam que o queijo artesanal de Alagoa pode ser classificado como de baixa umidade e gordo. Em relação à s caracterÃsticas sensoriais, os queijos apresentaram consistência tendendo a dura, textura tendendo a fechada sem olhaduras, cor interna amarelada, sabor moderadamente salgado e tendendo a picante, odor moderadamente pronunciado. Para a produção de queijos com qualidade e segurança microbiológica é necessária a implementação de boas práticas na produção de leite, incluindo programas de controle de mastite, brucelose e tuberculose, e de boas práticas na fabricação de queijos.bitstream/item/209185/1/BOP-41-Queijo-Artesanal.pd
Regulation of immunity during visceral Leishmania infection
Unicellular eukaryotes of the genus Leishmania are collectively responsible for a heterogeneous group of diseases known as leishmaniasis. The visceral form of leishmaniasis, caused by L. donovani or L. infantum, is a devastating condition, claiming 20,000 to 40,000 lives annually, with particular incidence in some of the poorest regions of the world. Immunity to Leishmania depends on the development of protective type I immune responses capable of activating infected phagocytes to kill intracellular amastigotes. However, despite the induction of protective responses, disease progresses due to a multitude of factors that impede an optimal response. These include the action of suppressive cytokines, exhaustion of specific T cells, loss of lymphoid tissue architecture and a defective humoral response. We will review how these responses are orchestrated during the course of infection, including both early and chronic stages, focusing on the spleen and the liver, which are the main target organs of visceral Leishmania in the host. A comprehensive understanding of the immune events that occur during visceral Leishmania infection is crucial for the implementation of immunotherapeutic approaches that complement the current anti-Leishmania chemotherapy and the development of effective vaccines to prevent disease.The research leading to these results has received funding from the European Community’s Seventh Framework Programme under grant agreement No.602773 (Project KINDRED). VR is supported by a post-doctoral fellowship granted by the KINDReD consortium. RS thanks the Foundation for Science and Technology (FCT) for an Investigator Grant (IF/00021/2014). This work was supported by grants to JE from ANR (LEISH-APO, France), Partenariat Hubert Curien (PHC) (program Volubilis, MA/11/262). JE acknowledges the support of the Canada Research Chair Program
Iron status and Helicobacter pylori infection in symptomatic children: an international multi-centered study
Objective:Iron deficiency (ID) and iron deficiency anaemia (IDA) are global major public health problems, particularly in developing countries. Whilst an association between H. pylori infection and ID/IDA has been proposed in the literature, currently there is no consensus. We studied the effects of H. pylori infection on ID/IDA in a cohort of children undergoing upper gastrointestinal endoscopy for upper abdominal pain in two developing and one developed country.Methods:In total 311 children (mean age 10.7±3.2 years) from Latin America - Belo Horizonte/Brazil (n = 125), Santiago/Chile (n = 105) - and London/UK (n = 81), were studied. Gastric and duodenal biopsies were obtained for evaluation of histology and H. pylori status and blood samples for parameters of ID/IDA.Results:The prevalence of H. pylori infection was 27.7% being significantly higher (p<0.001) in Latin America (35%) than in UK (7%). Multiple linear regression models revealed H. pylori infection as a significant predictor of low ferritin and haemoglobin concentrations in children from Latin-America. A negative correlation was observed between MCV (r = -0.26; p = 0.01) and MCH (r = -0.27; p = 0.01) values and the degree of antral chronic inflammation, and between MCH and the degree of corpus chronic (r = -0.29, p = 0.008) and active (r = -0.27, p = 0.002) inflammation.Conclusions:This study demonstrates that H. pylori infection in children influences the serum ferritin and haemoglobin concentrations, markers of early depletion of iron stores and anaemia respectively
Expression of neuropeptide Y and its receptors as affected by nutrition and leptin infusion in Zebu heifers
Effect of fiber digestibility and conservation method on feed intake and the ruminal ecosystem of growing steers
Fiber digestibility is an important factor regulating DMI in ruminants. Additionally, the ensiling process can also affect digestibility and chemical composition of the forage. The objective of this study was to investigate effects of sugarcane NDF digestibility (NDFD) and conservation method on intake, rumen kinetics, and the ruminal ecosystem of steers. Eight ruminally cannulated Nellore steers (275 ± 22 kg BW) were used in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments. Two sugarcane genotypes divergent for stalk NDFD were used: IAC86- 2480 with high NDFD and SP91-1049 with low NDFD. Experimental diets were formulated with 40% sugarcane, either freshly cut or as silage, and 60% concentrate on a DM basis. Each experimental period lasted for 14 d, with the last 4 d used for determination of intake, ruminal evacuation, and ruminal fluid collection. The effect of fiber digestibility on DM and NDF intake was dependent on the forage conservation method (P = 0.01). High NDFD increased (P < 0.01) DMI only when sugarcane was offered as silage, having no effect (P = 0.41) on DMI when offered as freshly cut. Conservation method had no effect on total ruminal mass, with only a tendency (P < 0.10) for greater NDF and indigestible NDF ruminal mass in steers fed the low-NDFD genotype. The NDF turnover and passage rates were greater (P < 0.05) for the genotype with high NDFD but only when offered as silage. Liquid turnover rate in the rumen was greater (P = 0.02) for diets containing silage, with no effect of genotype (P = 0.87). There was no effect of NDFD genotype on ruminal pH (P = 0.77); however, diets containing sugarcane as silage increased (P < 0.01) ruminal pH. Total concentration of short chain fatty acids (P = 0.05) and proportions of propionate (P = 0.01) were greater for diets containing fresh sugarcane. Diets with fresh sugarcane increased the ruminal population of Streptococcus bovis (P < 0.01) and Ruminococcus albus (P = 0.03). The relative population of R. albus was also greater (P = 0.04) for diets containing the sugarcane genotype with high NDFD. Feeding diets containing the sugarcane genotype with high NDFD increased Fibrobacter succinogenes population but only when sugarcane was fed as freshly cut (P = 0.02). Using sugarcane genotypes with high NDFD can increase intake and benefit fiber-degrading bacteria in the rumen
O uso do Kit Embrapa de Ordenha Manual® para produzir leite com qualidade: cartilhas elaboradas conforme a metodologia e-Rural.
E-BOOK: Espera-se que o uso do Kit, com suas variações e adaptações, possa contribuir muito com a melhoria da qualidade do leite produzido no Brasil e, com isso, aumentar a renda do produtor e a qualidade dos produtos lácteos que chegam às indústrias e ao consumidor.bitstream/item/149320/1/12-UsoKit-final.epubE-book, no formato ePub, convertido do livro impresso
Como identificar a vaca com mastite em sua propriedade: cartilhas elaboradas conforme a metodologia e-Rural.
CARTILHA: A mastite é a mais frequente doença das vacas de leite. É uma inflamação da mama provocada por alguns microrganismos ou germes. A identificação ou a confirmação da doença é realizado por meio de exames ou testes no campo "ao pé da vaca" ou no laboratório.bitstream/item/140323/1/Cartilha-Mastite-completa.pd
Nota de Conjuntura: Leite e Derivados - Janeiro/2020.
A oferta mundial de leite deve fechar 2019 com um tÃmido crescimento. Para 2020, a expectativa é de baixo crescimento na oferta e demanda internacional ainda aquecida, o que deve manter os preços internacionais firmes. No mercado interno, 2019 apresentou um comportamento de preços do leite diferente do padrão histórico. O aumento real nos preços do leite melhorou a relação de troca ao produtor. No atacado, os preços do leite UHT e da muçarela também apresentaram comportamentos distintos do padrão normal dos últimos anos. No varejo, a situação foi semelhante ao atacado. Confira essa análise completa com mais detalhes na NOTA DE CONJUNTURA da Plataforma de Inteligência Intelactus em sua edição de janeiro de 2020 que também analisa as expectativas para a atividade leiteira brasileira em 2020.bitstream/item/209217/1/Nota-Conjuntura-Jan-2020.pd