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Revista Brasileira de Zootecnia, Volume: 42, Número: 3, Publicado: 2013
  • Effect of water stress on the growth of Arachis pintoi plants under different nitrogen levels Forage Crops

    Sales, Rita Manuele Porto; Fries, Daniela Deitos; Bonomo, Paulo; Pires, Aureliano José Vieira; Campos, Cleide Nascimento; Brito, Paulo Henrique Rodrigues; Pereira, Iracema Souza; Santos, Joelma da Silva

    Resumo em Inglês:

    The objective was to evaluate the growth of Arachis pintoi fertilized with nitrogen and water deficiency conditions. The study was developed in a 4 × 4 factorial arrangement with four nitrogen levels (0, 40, 80 and 120 kg N/ha) and four irrigation levels (25, 50, 75 and 100% of field capacity), in a completely randomized experimental design, with four replications. High doses of N benefited the production of root shoots while the root increased its production at a dose of 40 kg N/ha. The number of green and senescent leaves were influenced by N fertilization and the water regime, where higher doses of N provided greater total number of green leaves (364 leaves/pot) and the limitation of water resulted in a greater number of senescent leaves (78 leaves/pot). Observing the maximum point, the water regime of 90% of field capacity and 120 kg N/ha favored leaf appearance rate of 1.2 leaves/day and less phyllochron (4.6 days/leaf) at 85% of field capacity and 115 kg N/ha. The dose of 120 kg N/ha resulted in ultimate greater width (1.4 cm) and length (2.4 cm) of the leaf at 100% of field capacity. The final length of stolons showed quadratic effect for N, having greatest length (58.1 cm) at 75 kg N/ha and 100% of field capacity.
  • Tillering dynamics in Guinea grass pastures subjected to management strategies under rotational grazing Forage Crops

    Zanine, Anderson de Moura; Nascimento Júnior, Domicio do; Sousa, Braulio Maia de Lana; Silveira, Márcia Cristina Teixeira da; Silva, Wilton Ladeira da; Santos, Manoel Eduardo Rozalino

    Resumo em Inglês:

    This study was carried out to analyze the tillering profile of Guinea grass (Panicum maximum cv. Tanzania) pastures subjected to two grazing frequencies (time necessary to intercept 90 and 95% of the incoming light) and two post-grazing heights (30 and 50 cm) in the period from November 2005 to October 2006. The experimental design was of completely randomized blocks with three replications, in a 2 × 2 factorial arrangement. At the end of the spring, pastures managed with 90% light interception showed greater tiller appearance rates in relation to pastures managed with 95%, regardless of post-grazing height. In the summer and fall, pastures managed with post-grazing height of 30 cm showed higher tiller appearance rates in comparison with pastures managed at 50 cm, regardless of grazing frequency. Concerning the tiller mortality rates, in the summer, higher values were found for pastures managed at 90/50 and 95/30 (interception/height), intermediate values at 90/30 and lower values in those managed at 95/50. Pastures managed at 90/30, 95/30 and 95/50 in the fall presented greater tiller mortality rates than those managed at 90/50. These differences do not occur in the winter/beginning of spring. The stability index remained above 1 all through the experimental period. All management strategies evaluated are adequate for Guinea grass.
  • Cattle farmers: profile and speech content analysis while undergoing training to adopt artificial insemination in Goiás State, Brazil Breeding, Genetics And Reproduction

    Gordo, João Maurício Lucas; Silva, Marcelo Corrêa da; Solano, Gianice de Almeida; Lopes, Fernando Brito; Costa, Marcos Fernando Oliveira e; Rocha, Francisco Eduardo de Castro; Fioravanti, Maria Clorinda Soares; Sereno, José Robson Bezerra

    Resumo em Inglês:

    This study was undertaken to verify major issues present in the discourse of cattle farmers when discussing the use of artificial insemination (AI). Seventy-one beef and dairy cattle farmers in the state of Goiás, Brazil, were interviewed using semi-structured questionnaires during AI training courses in 2010 and 2011. Data analyses were done using the classic method of textual speech content analysis, performing the pre-analytical, analytical and inferential stages. The written questions were separated in elementary context units (ECU) and sorted into similar thematic groups. These groups originated categories and subcategories, which were nominated based on an a posteriori criteria. Overall, personal motivation was the main issue characterizing discourse by farmers about adoption of AI. This motivation stems from the strong points (highlights) and positive expectations AI offers. The positive expectations were mainly related to perceptions of farmers of animal phenotype improvement rather than to the financial features of cattle production. Basic necessity was the second major issue, with emphasis on work force, infrastructure and animal handling, followed by social influence, with eminence of the institutions and people involved with AI and with the everyday life of cattle farmers. The little emphasis on human resource management and on the use of scientific knowledge may have affected the impact of AI over the years, explaining discreet indices of adoption of AI in Brazil.
  • Short, medium or long-term hormonal treatments for induction of synchronized estrus and ovulation in Saanen goats during the nonbreeding season Breeding, Genetics And Reproduction

    Pietroski, Ana Carolina Cunha Araujo; Brandão, Felipe Zandonadi; Souza, Joanna Maria Gonçalves de; Fonseca, Jeferson Ferreira da

    Resumo em Inglês:

    The objective of this study was to compare the effect of hormonal treatment duration through the use of intravaginal sponges impregnated with 60 mg MAP for 6 (G6; n = 10), 9 (G9; n = 10) or 12 (G12; n = 10) days. All nulliparous (n = 15) and lactating (n = 15) Saanen goats received 37.5 µg d-cloprostenol and 200 IU eCG 24 hours before sponge removal during the nonbreeding season. After sponge removal, estrus was monitored twice a day (06h00 and 18h00) by the use of fertile bucks. Transrectal ovarian ultrasonography was performed after device removal until ovulation detection. All goats were bred by artificial insemination (AI) or natural breeding (NB). All females received 250 IU hCG 5 d after AI or NB. No difference was observed among groups G6, G9 and G12 for: estrous response (90.0, 100.0 and 100.0%, respectively); interval from sponge removal to estrus (26.7±5.6, 25.2±2.8 and 25.2±3.3 hours), duration of estrus (28.5±7.1; 21.6±3.0 and 25.2±6.1 hours); ovulation rate (80.0, 100.0 and 70.0%); number of ovulations (1.9±0.2, 1.5±0.2 and 1.4±0.2); and pregnancy rate (60.0, 80.0 and 50.0%). Interval from sponge removal to ovulation was shorter in animals from G6 (44.6±2.2 hours) than for animals from G9 (52.8±2.7 hours) and G12 (60.0±4.5 hours). All treatments were effective in the induction of synchronized estrus in Saanen goats during the nonbreeding season, but ovulation occurred earlier when goats received sponges for 6 days.
  • Bioavailability and poultry fecal excretion of phosphorus from soybean-based diets supplemented with phytase Non Ruminants

    Martins, Bianca Almeida Brandão; Borgatti, Laura Maria de Oliveira; Souza, Luiz Waldemar de Oliveira; Robassini, Simi Luiza Durante Aflalo; Albuquerque, Ricardo de

    Resumo em Inglês:

    Five hundred and four 1-day-old Cobb broiler chickens were randomly allotted to 18 treatments and fed a semi-purified basal diet (4 g/kg total phosphorus) supplemented with 2 levels of supplemental P (0.5 or 1 g/kg) during 21 days to evaluate performance and bone mineralization; to assess the relative bioavailability of P (RBP) in wheat meal (WM) and roasted (RS) or extruded soybean meal (ES), with or without phytase (0 or 750 ftu/kg diet), using dicalcium phosphate (DC) as standard; and to estimate phosphorus excretion. Weight gain (WG), feed intake (FI), feed to gain ratio (FG), and tibia ash weigh (AW) were assessed. For each source, the RBP was calculated by the slope ratio method, when tibia ash weight was regressed on P ingested. Ingested and fecal P was determined to calculate P intake, and P excretion and excretion rate. Phytase addition increased overall FI, WG, and FG ratio by 3.3, 2.6 and 0.8%, respectively, but differences were not significant. Overall AW was increased by 10.8% after the enzyme inclusion in the diets. The relative bioavailability of phosphorus values of tested WM, RS, and ES were increased by 6.32, 64.32, 76.99%, respectively, in response to supplementation of phytase in diets containing WM, RS, and ES, respectively. Phytase reduced P excretion by 12.7% and the excretion rate by 15.0%, regardless of the phosphorus source or level.
  • Meat characteristics of Nellore steers fed whole cottonseed Ruminants

    Costa, Dorival Pereira Borges da; Roça, Roberto de Oliveira; Costa, Quézia Pereira Borges da; Lanna, Dante Pazzanese Duarte; Lima, Erico da Silva; Barros, Wander Miguel de

    Resumo em Inglês:

    The objective of this study was to evaluate the effect of addition of different levels of cottonseed (0, 14.35, 27.51 and 34.09 kg/100 kg) in the diet of Nellore steers on the meat characteristics. Thirty-six steers (average initial body weight of 333.50 and average age of 20 months) were kept in feedlot stalls for 94 days, each stall with three animals. The experiment was a completely randomized design with four treatments and nine replications. The values of protein, fixed mineral residue, shear force, lipid oxidation, meat color and fat color were similar among the treatments. The increase of the cottonseed levels in the diet reduced the amount of intramuscular fat and increased the moisture content in the meat linearly. Meat aroma and flavor were negatively influenced when cottonseed addition was greater than 27.51 and 34.09 kg/100 kg of the diet, respectively. Cottonseed diet did not modify the concentration of conjugated linoleic acid, saturated fatty acids or total unsaturated fatty acids, but linearly reduced the concentration of monounsaturated fatty acids in the meat.
  • Common factors method to predict the carcass composition tissue in kid goats Ruminants

    Gomes, Helen Fernanda Barros; Gonçalves, Heraldo Cesar; Polizel Neto, Angelo; Cañizares, Gil Ignacio Lara; Roça, Roberto de Oliveira; Marques, Raquel Ornelas; Oliveira, Giuliana Micai de; Queiroz, Edicarlos Oliveira

    Resumo em Inglês:

    The objective of this work was to analyze the interrelations among weights and carcass measures of the longissimus lumborum muscle thickness and area, and of sternum tissue thickness, measured directly on carcass and by ultrasound scan. Measures were taken on live animals and after slaughter to develop models of multiple linear regression, to estimate the composition of shoulder blade, from selected variables in 89 kids of both genders and five breed groups, raised in feedlot system. The variables considered relevant and not redundant on the information they carry, for the common factor analysis, were used in the carcass composition estimate development models. The presuppositions of linear regression models relative to residues were evaluated, the estimated residues were subjected to analysis of variance and the means were compared by the Student t test. Based in these results, the group of 32 initial variables could be reduced to four variables: hot carcass weight, rump perimeter, leg length and tissue height at the fourth sternum bone. The analysis of common factors was shown as an effective technique to study the interrelations among the independent variables. The measures of carcass dimension, alone, did not add any information to hot carcass weight. The carcass muscle weight can be estimated with high precision from simple models, without the need for information related to gender and breed, and they could be built based on carcass weight, which makes it easy to be applied. The fat and bones estimate models were not as accurate.
  • Rumen fermentation and rumen microbes in Nellore steers receiving diets with different lipid contents Ruminants

    Messana, Juliana Duarte; Berchielli, Telma Teresinha; Arcuri, Pedro Braga; Reis, Ricardo Andrade; Canesin, Roberta Carrilho; Ribeiro, Andressa Ferreira; Fiorentini, Giovani; Fernandes, Juliano José de Resende

    Resumo em Inglês:

    The objective of the present study was to evaluate the effects of dietary lipid content (20, 40 and 60 g/kg dry matter) on intake, total and ruminal apparent digestibility of dry matter (DM), nutrient digestibility, rumen fermentation parameters, microbial synthesis efficiency and rumen microbial content of beef cattle. Nine cannulated steers at 6 months of age with initial body weight of 232±35 kg were used in a triplicate 3 × 3 Latin square design. The results indicated that the total intake and digestibility of DM, organic matter (OM), gross energy (GE), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were not affected by the lipid content of the diet. However, the lowest lipid content diet reduced the total digestibility of crude protein (CP) and total carbohydrate linearly compared with the highest lipid diet. In contrast, when steers were fed a diet containing 20 g lipids/kg of DM, the concentration of ammonia in the rumen decreased quadratically relative to the other diets. Ruminal pH was not affected by the interaction of treatment and sampling time; however, the rumen pH decreased quadratically in animals that received the highest dietary lipid content (60 g/kg) compared with animals that received 20 and 40 g lipids/kg of DM. The rumen concentrations of volatile fatty acids, propionate, and butyrate and the acetate/propionate ratio were affected by the dietary lipid content. However, the microbial population, microbial N flow, and efficiency of synthesis were not affected by dietary lipid content. Overall, an increase in the lipid content of the diet of Nellore steers resulted in similar digestive profiles and fermentation conditions.
  • Replacement of corn by babassu mesocarp bran in diets for feedlot young bulls Ruminants

    Miotto, Fabrícia Rocha Chaves; Restle, João; Neiva, José Neuman Miranda; Castro, Kélvia Jácome de; Sousa, Luciano Fernandes; Silva, Rafael de Oliveira da; Freitas, Beatriz Barroso de; Leão, Jean Pacheco

    Resumo em Inglês:

    Nutrient intake and digestibility and productive performance of 30 feedlot young bulls fed diets containing babassu mesocarp bran in replacement of corn were evaluated. Animals were distributed in a completely randomized design with five levels of replacement of corn by babassu mesocarp bran (BMB): 0, 250, 500, 750 and 1000 g/kg of dry matter, and six replications. The dry matter (DM) intake in kg/day, g/kg body weight (BW) and g/kgBW0.75 increased as the corn was replaced by BMB. The intake of neutral detergent fiber (NDF) and crude protein (CP) increased linearly, whereas the intake of non-fibrous carbohydrates (NFC) had quadratic behavior. The digestibility of DM, CP, NDF and NFC and the total digestible nutrients (TDN) showed quadratic behavior with points of minimum digestibility of 850.0, 638.0, 867.0, 638.0 and 833.0 g/kg dry matter of replacement of corn by BMB, respectively. The final weight (476.82 kg) and average daily gain (1.55 kg/day) were not affected by experimental diets. The feed efficiencies of DM and CP decreased with increase in the levels of BMB, but the feed efficiency of TDN was not changed. Babassu mesocarp bran enables satisfactory performance, and depending on the price and opportunity cost, it can be utilized in the feeding of feedlot cattle totally replacing the corn of the diet.
  • Chilled boneless beef international trade: a cluster analysis Animal Production Systems And Agribusiness

    Pereira, Paulo Rodrigo Ramos Xavier; Barcellos, Júlio Otávio Jardim; Gründling, Roberta Dalla Porta; Canozzi, Maria Eugênia Andrighetto; McManus, Concepta; Lopes, Rúbia Branco

    Resumo em Inglês:

    The objective of this study was to measure and classify the international beef trade. For this, data related to the international chilled boneless beef (CBB) trade, the major and most important market, were analyzed. Producing countries were classified into groups according to their trade relations, and the main factors that influenced one country to prefer to import CBB from a specific exporting country were analyzed. The results revealed four markets related to client demands with regard to the sanitation and traceability of beef products. Furthermore, extrinsic characteristics of the product are discussed, such as a productive system that aims to minimize environmental impacts and to value animal welfare and respect for social demands. The markets that pay highest prices require sanitary quality of suppliers, demanding traceable and process-certified products. Brazil does not access these markets because it does not meet these requirements. To change this scenario it is necessary to eradicate FMD across the Brazilian territory, acquiring a status of a zone with minimal BSE risk, aligning the intrinsic value of the CBB with expectations of consumers and implementing a traceability program that is both feasible and acceptable for clients.
Sociedade Brasileira de Zootecnia Universidade Federal de Viçosa / Departamento de Zootecnia, 36570-900 Viçosa MG Brazil, Tel.: +55 31 3612-4602, +55 31 3612-4612 - Viçosa - MG - Brazil
E-mail: rbz@sbz.org.br