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Search Results: 1 - 10 of 94 matches for " bovines "
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Estudio seroepidemiológico del virus respiratorio sincitial bovino en el municipio de Montería, Colombia
Betancur H,César; Rodas G,Juan; González T,Marco;
Revista MVZ Córdoba , 2011,
Abstract: objective. to detect specific antibodies against the bovine respiratory sincitial virus (brsv) through a commercial elisa kit (bio-x ? brsv elisa kit, bruselas, bélgica) in order to have an indirect evidence of brsv circulation, municipality of monteria, colombia. materials and methods. a total of 163 blood samples were randomly collected (137 females and 26 bulls) from 28 farms belonging to 4 different equidistant zones and with an history of reproductive disorders. a descriptive x2 analysis was performed to compared the serological results from each animal on breed, age, zone, type of production, sex and reproductive disorders. results. there were no differences for any of the variables studied. antibodies for brsv were detected in 13% (22/163) of the animals. conclusions. the results show an indirect evidence of the presence of brsv in animals belonging to the region studied. this suggests the need for additional studies in order to determine the participation of brsv on respiratory and reproductive problems. if case of clinic implications, it would be necessary to implement appropriate control measures to prevent viral dissemination.
Osorio,José Henry; Vinazco,Jazmín;
Biosalud , 2010,
Abstract: objective: to analyze the bovine lipid metabolism and its relation with the diet, corporal condition, productive state and associated pathologies. materials and methods: available literature from the past 50 years found in the bbcs-lilacs, academic sources, ib-psycinfo, ib-ssci, ib-scielo, scopus and scirus data bases was analyzed, as well as historical articles, and texts and references cited in public works. results: pertinent information related with the proposed objectives for this revision was obtained which can be classified in seven sections as follows: rumen function in the lipid metabolism, fatty acids metabolism by rumen, liver and lipid metabolism in bovines, diet and lipid metabolism in bovines, lipids and corporal condition in bovines, lipids and productive state in bovines, associated pathologies. conclusion: the bovines anatomy and physiology allows them to be considerably differentiated from the monogastric species, mainly because of the biochemical and physiological aspects, since the bacteria and the rumen flora can synthesize, assimilate and modify dietary lipids in a different way because of the triglycerides synthesis speed and the type of saturated and unsaturated fatty acids which influence the formation and transportation of lipids.
Estima??o de parametros genéticos entre pesos pré e pós-desmama na ra?a Nelore
Garnero,A.V.; Mu?oz,M.C.C.D.; Marcondes,C.R.; L?bo,R.B.; Lira,T.; Gunski,R.J.;
Archivos de Zootecnia , 2010, DOI: 10.4321/S0004-05922010000200019
Abstract: correlations among two or more traits indicate the extent to which they are associated. the level and magnitude of this association are key factors in genetic improvement because the goal is to enhance the genetic makeup of a group of traits that act simultaneously. therefore, the aim of this study was to estimate the components of variance and heritability for standard weights at 120, 240, 365, 450 and 550 days of age (p120, p240, p365, p450 and p550, respectively), and the genetic correlation among p120 and other weights in nellore cattle using a database of 29 769 records. bivariate analysis was carried out for all the traits using p120 as an anchor, and additive covariance was fixed as an analytical strategy in order to obtain genetic correlation estimates. heritability (h2) values were 0.21 for p240; 0.37 for p365; 0.36 for p450 and 0.42 for p550. the estimation of h2 varied between 0.23 and 0.31 for w120. genetic correlation estimates were high and positive, 0.96, 0.87, 0.79 and 0.76 among p120 and p240, p365, p450 and p550, respectively. these values indicate that selection for weight at younger ages will lead to a corresponding change in later weight, in the same direction.
Prevalencia de anticuerpos séricos contra Neospora caninum en dos reba?os lecheros de la IX Región de Chile
Archivos de medicina veterinaria , 2000, DOI: 10.4067/S0301-732X2000000200008
Abstract: neosporosis is an important cause of economic loss in the cattle industry throughout the world. in chile, it has been recently detected and,. since then, veterinarians and producers have required information about different aspects of the disease. in this paper we present data of the prevalence of the disease in two dairy herds of the ix region of chile. a commercial indirect fluorescent antibody test (ifa) was performed at 1:200 dilution for bovine and at 1:50 for canine sera. results indicate a 30.2% (52/173, ic=6.8%) infection in bovines from farm "a" and a 15.7% (31/198, ic=5%) in bovines from farm "b" (c2 = 10.42, p = 0.0012). in addition, 57% (4/7) of the dogs from farm "a" had antibodies. differences were observed in each farm as well as amongst age groups: in farm "a" 39.6% (42/106) of heifers and 15.2% (10/66) of cows (c2=10.42, p=0.0012) had antibodies against n. caninum; in farm "b": 22.7% (15/66) of calves, 17.8% (8/45) of heifers and 9.2% (8/87) of cows were positive. there were differences amongst cows, calves and heifers groups (c2=4,07, p=0.043). although it was not the aim of the study it is discussed if the source of infection could be the cause of the difference in prevalence. in contrast with farm "b"," the higher prevalence in farm "a was related to the group fed also with supplements. how the disease spreads in our environment is unknown, different mechanisms could be involved since in most of the farms the animals spend half of the year under confinement and the other half on pasture. the present article gives values of neospora prevalence and preliminary data for further studies on this progressively important disease
Vitrificación de ovocitos bovinos y su uso en el desarrollo partenogenético de embriones
Ruiz,J; Correa,JE; Martínez,M;
Archivos de medicina veterinaria , 2010, DOI: 10.4067/S0301-732X2010000100011
Abstract: the aim of this study was to evaluate vitrification effects on the viability of chemically activated oocytes in order to produce parthenogenetic bovine embryos. bovine oocytes retrieved from ovaries obtained in a slaughterhouse were matured in vitro for 20-22 hours and then assigned to the following groups: i (n=76): vitrified/thawed oocytes, ii (n=119): exposed oocytes to cryoprotectans without vitrification and iii (n=142): control oocytes. bovine oocytes were vitrified in microdrops on a precooled aluminum foil floating in liquid nitrogen, using an equilibrium solution with 4% ethylene glycol and a vitrification solution with 35% ethylene glycol, 5% polyvinyl-pyrrolidone and 0,4 m trehalose. the vitrified microdrops were stored in liquid nitrogen and were thawed after 1-3 days of storage. the oocytes of the 3 groups were parthenogenetically activated by 4-min exposure to 5 μm ca ionomycin at room temperature followed through 5 hours incubation in 6-dimethylaminopurine at 38.5 oc in a 5% co2 in humidified atmosphere. embryos were cultivated on msof medium during 8-9 days. the rates of oocytes survival were 55.1% and 93.7% to vitrified/thawed (i) and exposed (ii) oocytes respectively. the rates of cleavage were 55.3%, 72.3% and 74.6%; and development to blastocysts were 7.1%, 17.4% and 21.7% in groups i, ii and iii respectively. these results demonstrate that the oocyte vitrification technique has been set up in our laboratory and parthenogenetic bovine embryos can be produced from such as vitrified/thawed oocytes.
Primeiro registro de Trypanosoma vivax em bovinos no Estado do Rio Grande do Sul, Brasil
Silva, Aleksandro Schafer da;Costa, Marcio Machado;Polenz, Mauro Flores;Polenz, Carlos Henrique;Teixeira, Marta Maria Geraldes;Lopes, Sonia Terezinha Dos Anjos;Monteiro, Silvia Gonzalez;
Ciência Rural , 2009, DOI: 10.1590/S0103-84782009005000189
Abstract: this study aimed at reporting the occurrence of trypanosoma vivax in southern brazil. the protozoan was diagnosed through peripheral blood smear evaluation of a bovine and confirmed by the evaluation of the trypomastigote forms morphology and by the polimerase chain reaction (pcr). the animal showed clinical signs similar to the nervous form of the infection by t. vivax. negative results for t. vivax were found in other bovines grazing in the same paddock. this is the first report of t. vivax in the state of rio grande do sul and in the southern region of brazil.
Contagem de células somáticas e produ??o de leite em vacas holandesas de alta produ??o
Coldebella, Arlei;Machado, Paulo Fernando;Demétrio, Clarice Garcia Borges;Ribeiro Júnior, Paulo Justiniano;Corassin, Carlos Humberto;Meyer, Paula Marques;Cassoli, Laerte Dagher;
Pesquisa Agropecuária Brasileira , 2003, DOI: 10.1590/S0100-204X2003001200012
Abstract: the goal of this paper was to evaluate if losses in milk yield due to increase in somatic cells count are proportional or independent of the level of production. a total of 7,756 observations, monthly collected from a single herd from september/2000 up to june/2002, were used. the lactation curve was modeled by the incomplete gamma function, considering the effects of lactation order, calving season, peripartum disorder incidence and body condition score at calving. somatic cells count was added to the model as a multiplicative factor, representing relative losses, and as an additive factor, representing absolute losses. the best model was chosen based on the information criteria of schwarz (bic). the losses are absolute, becoming evident from 14,270 cells/ml, and they are 184 and 869 g/day for each increase of one unit in the natural logarithm scale, starting from that somatic cells count, for primiparous and multiparous cows, respectively.
Congela??o de ovócitos desnudados ou n?o, maturos e imaturos de bovinos, utilizando o Etileno Glicol pelo método convencional
Fagundes, Letícia Martins;Costa, Eduardo Paulino da;Torres, Ciro Alexandre Alves;Amaral Filha, Wald'ma Sobrinho;Guimar?es, José Domingos;
Revista Brasileira de Zootecnia , 2004, DOI: 10.1590/S1516-35982004000800014
Abstract: the objective of this study was to evaluate the cryopreservation of in vitro mature or immature oocytes by conventional method. the experiment was conducted using oocytes of cows' ovaries from slaughterhouse, distributed into six treatments: unfrozen oocytes with the cumulus oophorus cells (t1) and naked (t2) which were submitted to the process of miv, fiv and civ; immature oocytes, with the cumulus oophorus cells (t3) and naked (t4), which were submitted to the cryopreservation, unfrozen and the miv, fiv and civ; oocytes with the cumulus oophorus cells (t5) and naked (t6), which were submitted to in vitro maturation, cryopreservation, and fiv and civ. the oocytes were frozen by the conventional methods, dehydrated by the immersion in three solutions with 0.6; 1.2 and 1.8 mol l-1 of ethylene glycol (eg) during 5 minutes each phase. the thawing phase was done by the immersion in water-bath at 30 oc during 20 seconds, and so, the oocytes were re-hydrated in three phases (0.9 mol l-1 eg + 0.3 mol l-1 of sacarose; 0.3 l-1 of sacarose without eg and sacarose) for six minutes each one. the mainly ultrastructural changes in cryopreserved matured oocytes were prematurely released of cortical granules. however, the frozen immature and mature oocytes showed vacuolization and disappearance of cristae mitochondrial. the frozen immature oocytes showed the maturation rate of 82.5, 75.4, 9.2 and 5.8% for t1, t2, t3 and t4, respectively. the fecundation rate were 56.2, 0.0, 38.7, 8.6, 63.6 and 16.7% and from the cleavage were 36.3, 7.9, 0.4, 0.0, 0.0 and 0.0% for t1, t2, t3, t4, t5 and t6, respectively. morula and blastocyst were observed only for unfrozen and naked oocytes (t1) (34.5%). these results showed that the frozen protocols affect the viability of the oocytes.
Níveis de concentrado em dietas de novilhos mesti?os F1 Simental x Nelore: 1. Consumo e digestibilidades
Tibo, Gilson Camargo;Valadares Filho, Sebasti?o de Campos;Valadares, Rilene Ferreira Diniz;Silva, José Fernando Coelho da;Cecon, Paulo Roberto;Le?o, Maria Ignez;Silva, Rosane Barros da;
Revista Brasileira de Zootecnia , 2000, DOI: 10.1590/S1516-35982000000300037
Abstract: an experiment was carried out to evaluate the dietary concentrate levels on the intake, total and partial apparent digestibilities of dry matter (dm), organic matter (om), crude protein (cp), ether extract (ee), total carbohydrates (cho), neutral detergent fiber (ndf) and non structural carbohydrates (nec). the effects of samples collections, realized on the day or the night, on the total and partial apparent digestibilities of dm and om, were studied. five f1 simental x nellore bulls fistulated in the rumen, abomasum and ileum, full fed diets with 25.0, 37.5, 50.0, 62.5, and 75.0% of concentrate and allotted to 5 x 5 latin square, were used. the hays of brachiaria (brachiaria decumbens, stapf) and coast-cross grasses (cynodon dactylon) were used in the same proportions. the chromic oxide was used as indicator to determine the digesta flows and fecal excretion. the addition of increasing amounts of concentrate to the diet resulted in linear increases in the dm, om, cp, ee, cho, nec and tdn intakes and reduction in the ndf intake. the total apparent digestibilities of dm, om, cp, ee, cho, nec and tdn linearly increased with the increasing concentrate levels. the concentrate levels did not influence the ndf apparent digestibilities in the rumen and post-rumen. the reduction in the dietary ndf levels resulted in tdn linear increases and dm total apparent digestibility. feces and abomasum and ileum digesta representative samples can be obtained using collections only during the day.
Consumo e digest?es totais e parciais em novilhos F1 Limousin x Nelore alimentados com dietas contendo cinco níveis de concentrado
Dias, Helder Luis Chaves;Valadares Filho, Sebasti?o de Campos;Coelho da Silva, José Fernando;Paulino, Mário Fonseca;Cecon, Paulo Roberto;Le?o, Maria Ignês;Oliveira, Rodrigo Vidal de;
Revista Brasileira de Zootecnia , 2000, DOI: 10.1590/S1516-35982000000200031
Abstract: abstract - a trial was conducted to evaluate the effects of five dietary concentrate levels on the intake and total and partial apparent digestibility of dry matter (dm), organic matter (om), crude protein (cp), ether extract (ee), total carbohydrates (cho), neutral detergent fiber (ndf), and non structural carbohydrates (nsc). five rumen, abomasum and ileum fistulated f1 limousin x nellore bulls were full fed diets containing 25.0, 37.5, 50.0, 62.5, and 75.0% of concentrate and allotted to a 5 x 5 latin square design. the chromic oxide was used as an external marker to determine the total and partial digestibility. the addition of crescent concentrate amounts to the diet resulted in linear increases in the dm, om, nce, cp, ee, and tdn and reductions in ndf intake. the total apparent digestibility of dm, om, cp, ee, cho, and nsc linearly increased with the increment of the dietary concentrate levels. the cp apparent digestibility in the small intestine linearly increased as function of the concentrate addition in the diets. the concentrate levels in the diet did not influence the rumen and post-rumen ndf apparent digestibility. the dietary ndf levels reduction resulted on linear increases of ndt and dm total apparent digestibility.
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