Centro de Ciências Agrárias
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11727
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Item Strategies for commercialization of cryopreserved fish semen(Brazilian Journal of Animal Science, 2008) Tiersch, Terrence R.Initial success in sperm cryopreservation occurred at about the same time for aquatic species and livestock. However, in the 50 plus years since then cryopreserved sperm of livestock has grown into a billion-dollar global industry, while cryopreserved sperm of aquatic species remains a research activity with little commercial application despite work in more than 90 species and more than 200 published reports. Most research work has focused on large-bodied culture and sport fishes, such as salmon, trout, carp, and catfish, and mollusks such as commercially important oyster and abalone species. However, only a few studies have addressed sperm cryopreservation in small fishes such as zebrafish, or in endangered species. Overall, this work has yielded techniques that are being applied with varied levels of success around the world. Barriers to expanded application include a diverse and widely distributed literature base, technical problems, small sperm volumes, variable results, a general lack of access to the technology, and most importantly, a lack of standardization in practices and reporting. The benefits of cryopreservation include at least five levels of improvements for existing industries and for creation of new industries. First, cryopreservation can be used to improve existing hatchery operations by providing sperm on demand and simplifying the timing of induced spawning. Second, frozen sperm can enhance efficient use of facilities and create new opportunities in the hatchery by eliminating the need to maintain live males, potentially freeing resources for use with females and larvae. Third, valuable genetic lineages such as endangered species, research models or improved farmed strains can be protected by storage of frozen sperm. Fourth, cryopreservation opens the door for rapid genetic improvement. Frozen sperm can be used in breeding programs to create improved lines and shape the genetic resources available for aquaculture. Finally, cryopreserved sperm of aquatic species will at some point become an entirely new industry itself. A successful industry will require integrated practices for sample collection, refrigerated storage, freezing, thawing, rules for use and disposal, transfer agreements, and database development. Indeed the development of this new industry is constrained by factors including the technical requirements for scaling-up to commercial operations during the transition from research, and the absence of uniform quality control practices, industry standards, and appropriate biosecurity safeguards.Item Growth hormone-insuline-like growth factor-I system in pejerrey Odontesthes bonariensis (Atheriniformes)(Brazilian Journal of Animal Science, 2008) Arranz, S. E.; Sciara, A. A.; Botta, P.; Cerutti, P.; Tobin, M.; Somoza, G. M.Using biotechnology to increase the growth rates of fish is likely to reduce production costs per unit of food. Among vertebrates, fish appear to occupy a unique position, when growth patterns are considered. With few exceptions, fish species tend to grow indeterminately, implying that size is never fixed. Both hyperplasia and hypertrophy contribute to post-larval muscle growth in fish. Growth hormone (GH) - Insulin-like Growth Factor I (IGF-I) is the most important growth axis in fish. Our experimental model, the pejerrey, Odontesthes bonariensis (Ateriniformes) is a South American inland water fish considered to be a promising species for intensive aquaculture. However, one major drawback to achieve this goal is its slow growth in captivity. In order to understand how growth is regulated in this species, our first objective was to characterized pejerrey GH- IGF-I axis. We first cloned and characterized pejerrey (pj) GH, IGF-I and the growth hormone receptors (GHRs) I and II. In addition to providing valuable data for evolutionary comparison of GH, investigation of GH action in teleosts is particularly important because of its potential application in aquaculture. GH can not only promote the somatic growth in fish but also lower dietary protein requirements. A prerequisite for providing sufficient amounts of GH for basic research and aquaculture application is a large-scale production of GH. For that purpose, recombinant pjGH was expressed in a bacterial system. Protocols for solubilization and proper folding were achieved. Activity of recombinant pjGH was assessed in fish by measuring the liver IGF-I response to different doses of GH. IGF-I transcript was measured in the liver after pjGHr in vivo stimulation by means of quantitative real-time PCR assays. A dose-dependent response of IGF-I mRNA was observed after pjGHr administration, and reached a 6 fold IGF-I maximum increase over control group when 2.5 μg pjGH /g-body weight were injected. Temporal analysis of hepatic IGF-I mRNA levels showed that administration of a single dose of pjGHr into juvenile pejerrey resulted in a significant increase (P<0.02) 9 hours post injection. These results demonstrates that recombinant pjGH could promote a dramatic response in liver, increasing the IGF-I mRNA level. We also study the effect of GH on muscle growth after oral administration. A significant association between GH doses and mean fiber area (MFA) was observed even with a caloric restrictive diet. MFA increased 3.7 μm2 per each unit of GH supplied indicating that GH promoted white muscle hypertrophy. These preliminary data indicates that GH could be absorbed by the intestine in an active form and promote somatic growth.Item Cobia (Rachycentron canadum) hatchery-to-market aquaculture technology: recent advances at the University of Miami Experimental Hatchery (UMEH)(Brazilian Journal of Animal Science, 2010) Benetti, Daniel; Sardenberg, Bruno; Hoenig, Ron; Welch, Aaron; Stieglitz, John; Miralao, Sasa; Farkas, Daniel; Brown, Patrick; Jory, DarrylAmong warm-water marine fishes, cobia is one of the best aquaculture candidate species in the world. Currently there are commercial culture operations in several Asian countries and the industry has started developing elsewhere, including the Western Central Atlantic region. Significant research has been conducted at the University of Miami’s Aquaculture Program / University of Miami Experimental Hatchery (UMEH) during the last eight years, involving research to develop and optimize advanced technology to demonstrate the viability of raising hatchery-reared cobia in collaboration with the private sector. This paper reviews some of this recent advances for the development of Hatchery-to-Market Aquaculture Technology for commercial production of cobia.Item Reflexos de políticas públicas sobre a fruticultura cearense: o caso do Agropolo Baixo Jaguaribe(Revista de Economia e Agronegócio, 2004) Matias, Gerlan Dayvid Viana; Silva, Lúcia Maria Ramos; Khan, Ahmad SaeedEste estudo teve como objetivo analisar o impacto do Programa Cearense de Agricultura Irrigada – PROCEAGRI na fruticultura do Estado do Ceará, considerando-se o caso do Agropolo Baixo Jaguaribe. Os dados utilizados foram obtidos de entrevistas diretas com os produtores de frutas dos municípios de Aracati, Limoeiro do Norte e Quixeré. Em todos esses municípios, após 1998 (implantação do referido Programa) houve melhorias no aspecto tecnológico e incremento na produtividade. Um beneficio importante gerado no Agropolo Baixo Jaguaribe foi a criação de empregos, na sua maioria locais. Sugere-se a concessão de incentivos à instalação de agroindústrias para melhor aproveitamento das frutas, aumento da oferta de crédito, mais assistência técnica, garantia de comercialização e melhoria da infra-estrutura.Item Comércio exterior de produtos agrícolas do estado do Paraná de 1989 a 2001: análise de vantagens comparativas e do padrão de comércio(Revista de Economia e Agronegócio, 2004) Rosa, Tatiana Diair Lourenzi Franco; Alves, Alexandre FlorindoNeste artigo, objetivou-se discutir a evolução das vantagens comparativas no comércio de produtos agrícolas do Estado do Paraná, no período de 1989-2001, bem como verificar o tipo de comércio predominante nesse gênero de produtos. A metodologia baseou-se no cálculo de indicadores de Vantagem Comparativa Revelada (Balassa, 1965), Taxa de Cobertura e Comércio Intra-Indústria (Grubel e Lloyd, 1975). Os resultados a respeito das vantagens comparativas de produtos agrícolas pertencentes à Seção II da NBM-NCM indicaram que os capítulos referentes a café, chá, mate e especiarias e sementes e frutos oleaginosos, grãos etc. representam “pontos fortes” da economia paranaense. Embora a Seção de Produtos do Reino Vegetal tenha se caracterizada pela predominância de comércio intra-indústria, os índices de Grubel e Lloyd evidenciaram que, em todos os capítulos pertencentes a essa seção, ainda predomina o comércio do tipo interindustrial.Item Tifton 85 bermudagrass (Cynodon sp.) silage as a replacement for Tifton 85 hay to feed lactating cows(Brazilian Journal of Animal Science, 2017-09-01) Avila, André Sanches de; Zambom, Maximiliane Alavarse; Faccenda, Andressa; Eckstein, Everline Inês; Anschau, Fernando André; Garcias, Jessica; Schneider, Cibele Regina; Fornari, Josias LuisThe objective of the study was to evaluate the replacement of Tifton 85 hay (TH) for Tifton 85 silage (TS) in the diets of lactating cows. Five Holstein cows in middle of lactation were allocated in a 5 × 5 Latin square design and each experimental period lasted 18 days (12 days for adaptation and six days for collection). Treatments consisted of replacement of 0, 25, 50, 75, and 100% of TH for TS. The intake and digestion of nutrients, microbial protein synthesis, milk yield and composition, and the economic viability of the diets were evaluated. The intakes of dry matter, organic matter, and ether extract had a positive linear effect and the digestibility of dry matter, organic matter, crude protein, neutral detergent fiber, acid detergent fiber decreased linearly with increasing participation of TS. Milk production and composition and microbial protein synthesis were not affected. Regarding economic viability, the treatment with 100% hay produced better results, with better gross margin. The Tifton 85 silage can be used as a replacement for Tifton 85 hay up to 100% without changing the milk production and composition of Holstein cows.Item New approaches, development, and improvement of methodologies for the assessment of B-vitamin requirements in dairy cows(Brazilian Journal of Animal Science, 2017-07-01) Girard, Christiane L.Studies on B-vitamin requirements of cattle, conducted more than 60 years ago, concluded that mature ruminants do not require B-vitamin supplements because the amounts of vitamins provided by the diet and synthesized by the ruminal microflora were sufficient to prevent emergence of deficiency symptoms. As a result, the impact of subclinical deficiency on maintenance of normal and efficient metabolism has been disregarded and very little research effort has been devoted at defining dairy cow requirements for B vitamins. However, emergence of deficiency symptoms is the last stage of the deficiency; deficiency appears as soon as the supply is inferior to the needs, leading to a loss of metabolic efficiency. As B vitamins play critical roles in carbohydrate, protein, and lipid metabolism, it is likely that the demand for these cofactors increases with milk yield. Reports over the last two decades of beneficial effects of B-vitamin supplementation, such as thiamin, niacin, biotin, folic acid, and vitamin B12, suggested that, under some conditions, the need for B vitamins exceeds the supply from the diet and the synthesis by rumen microbes, leading to sub-optimal milk production and metabolic efficiency. However, responses to B-vitamin supplementation are highly variable. The major challenge faced by studies on B-vitamin requirements of dairy cows is the very limited knowledge on dietary factors driving the fate of B vitamins in rumen. This knowledge is essential to identify the conditions under which the dairy cow could benefit from B-vitamin supplements. The present review aims to describe the present state of knowledge on B-vitamin requirements of dairy cows as well as some of the major problems that need to be overcome to progress in this research field.Item Substitution of blood plasma with soy protein concentrate in piglet diet(Brazilian Journal of Animal Science, 2017-04-01) Resende, Moisés Queiroz; Mascarenhas, Alessandra Gimenez; Mello, Heloisa Helena de Carvalho; Arnhold, Emmanuel; Teixeira, Karla Andrade; Rufino, Luciana Moura; Nunes, Romão da CunhaIn this study, we evaluated the effects of substitution of partial and total spray-dried blood plasma (BP) with soy protein concentrate (SPC) in the diet of post-weaning piglets on their performance, intestinal histomorphometry, and blood parameters. Fifty-four castrated male piglets, weaned at an average age of 21 days and an initial average weight of 7.01±0.294 kg, were distributed in a completely randomized block design, with three diets (0%SPC-5%BP, 2.5%SPC-2.5%BP, and 5%SPC-0%BP), six replicates, and three piglets per experimental unit. The experimental feeds were formulated to meet the requirements of the piglets at 21-32 and 33-42 days of age (pre-starter diet) and 43-66 days of age (starter diet). From 21 to 32 and 21 to 42 days of age, daily feed intake, daily weight gain, and final weight of the animals were higher in the group fed 2.5%SPC-2.5%BP and 0%SPC-5%BP. From 21 to 66 days of age, daily weight gain and daily feed intake were higher in the animals fed 2.5%SPC-2.5%BP. No effect was observed on the histomorphometry variables. The total leukocyte count was higher in animals fed 2.5%SPC-2.5%BP and 5%SPC-0%BP and the lymphocyte count was lower in the piglets that received 0%SPC-5%BP. The combined use of soy protein concentrate and spray-dried blood plasma in the feeds of piglets between 21 and 42 days of age improves their productive performance.Item Sheep meat commercialization in the retail market in Brazilian cities(Brazilian Journal of Animal Science, 2018-01-01) Firetti, Ricardo; Alberti, Ana Lúcia Luz; Zundt, Marilice; Santos, Aline de Oliveira; Rego, Fabiola Cristine de Almeida; Astolphi, José Luis de LimaThis paper explored the mix market characteristics of sheep meat as a product for sale in different cities in the states of São Paulo and Paraná. For this, 81 products were purchased in 21 outlets sampled in a “non-probabilistic” manner for convenience and then subjected to analysis of yield of meat, bone, and fat. Imported products represented 20% of the total, being marketed in hypermarkets. It was observed that 37% of the total products were obtained in hypermarkets, 31% in supermarkets, 23% in butcher shops, and 8.6% in meat outlets. Almost 9% of the products had not undergone the official slaughter inspection system. The main types of products identified were palettes and legs with bones (33.3 and 24.7%, respectively); however, only 25% were satisfactorily displayed to consumers. The yields obtained in meat and deboned portions were 74% and 59% of the total weight, significantly affecting the average adjusted sales prices of the products, respectively US$13.01/kg sale price; US$17.82/kg deboned; and US$22.52/kg lean meat. The low yield of clean and boned meat observed in the samples can lead to negative experiences of these products by consumers.Item Effect of the dietary level of cull pinto beans (Phaseolus vulgaris) on ruminal fermentation, kinetics, and digestibility of hair lambs(Brazilian Journal of Animal Science, 2017-05-01) Castillo Rangel, Francisco; Villalobos Villalobos, Guillermo; Domínguez Díaz, David; Ortega Gutiérrez, Juan ÁngelThe objective was to evaluate the effect of three levels of cull pinto beans (CPB; Phaseolus vulgaris) on ruminal fermentation, kinetics, and nutrient digestibility in hair lambs. Six cannulated lambs averaging 56.6±3.8 kg were used and were randomly assigned to one of three treatments. Treatments were: 0.0 kg kg–1 of CPB in the supplement (control); 0.25 kg kg–1 of CPB in the supplement (CB25); and 0.40 kg kg–1 of CPB in the supplement (CB40). Dry matter intake, ruminal pH, NH3 , and volatile fatty acid (VFA) concentration, methane production, Kp (passage rate), MRT (mean retention time), and digestibility of dry matter, crude protein, and neutral detergent fiber were evaluated. Data were analyzed in a Latin square design, repeated in line, by MIXED procedure of SAS. Estimates used for Kp and MRT were obtained by a non-linear regression model (PROC NLIN). Dry matter intake was reduced by supplementation of CPB. No differences were found in ruminal pH or ruminal NH3. During the trial, differences were found for ruminal VFA concentration (mM), which were greater for the CB25 group. The propionate:acetate ratio was greater for the CB40 treatment. Methane production (mM/m) differed among treatments, but it was the greatest for the CB40 group. Passage rate (kg kg–1/h) and MRT (h) were similar among treatments and the digestibility (kg kg–1) of dry matter, crude protein, and neutral detergent fiber was not different among treatments. The inclusion of 0.25 kg kg–1 of CPB in the diet of hair lambs allows for appropriate nutrient digestion without affecting Kp and MRT and increases the molar proportion of the ability of VFA to maintain acetate:propionate ratio without increasing methane production.