Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-12-22T16:12:09Z No. of bitstreams: 2 luyde_pena_linhares.pdf: 430275 bytes, checksum: dcc4a041aa592c20647f510202caf398 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-12-22T16:56:24Z (GMT) No. of bitstreams: 2 luyde_pena_linhares.pdf: 430275 bytes, checksum: dcc4a041aa592c20647f510202caf398 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2015-12-22T16:56:24Z (GMT). No. of bitstreams: 2 luyde_pena_linhares.pdf: 430275 bytes, checksum: dcc4a041aa592c20647f510202caf398 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2012 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Objetivou-se avaliar a aplica??o suplementar de quatro doses de ocitocina ex?gena (0, 5, 10, 15 UI) na remo??o do leite residual e os par?metros de produ??o da ordenha, produ??o de leite residual, produ??o total, porcentagem em rela??o ? ordenha total, composi??o e incid?ncia de mastite atrav?s da contagem de c?lulas som?ticas (CCS). O experimento foi conduzido em uma propriedade particular, tipicamente leiteira, localizada no munic?pio de Francisco S?, regi?o Norte de Minas Gerais, durante os meses de fevereiro a junho de 2012. Foram utilizados 20 vacas mesti?as Holand?s-Guzer?, mantidas a pasto com suplementa??o proteica, clinicamente sadias, com grau sangu?neo variando entre animais 3/4 e 7/8, mult?paras, com ordem de parto entre segunda a quinta lacta??o, com 60 dias p?s-parto e produ??o m?dia entre 7 e 13 kg de leite. O delineamento utilizado para as vari?veis de produ??o e composi??o foram inteiramente casualizado (DIC), com repeti??o no tempo (nove semanas). Foi feita a regress?o na an?lise de varia??o. Para verificar a depend?ncia entre a preval?ncia de mastite e as doses suplementares de ocitocina foram realizadas an?lises estat?sticas com teste de Qui-quadrado, sendo os valores dos resultados considerados significativos quando P < 0,01. O volume de leite oriundo da ordenha plena apresentou vari?ncia (P<0,01) e comportamento quadr?tico em rela??o ?s doses suplementares, apresentando nas doses de ocitocina superiores a 5 UI. A produ??o de leite residual apresentou comportamento semelhante, sendo a dose de 10 UI a que melhor promoveu a remo??o do leite residual e consequente produ??o. A produ??o total de leite tamb?m foi influenciada (P<0,01) pela administra??o de ocitocina ex?gena, com maior produ??o acima da dose de 5UI, decrescendo abruptamente com as doses de 10 e 15 UI. A porcentagem de leite residual apresentou mesmo signific?ncia e distribui??o dos dados quadraticamente, com remo??o de 12,3 % de leite residual com a maior dose 15 UI. Na composi??o do leite residual, observou-se signific?ncia (P<0,05) somente quanto ? gordura, n?o apresentando vari?ncia significativa quanto ? lactose e prote?na. A gordura, comportando quadraticamente, obteve maior teor no leite residual quando administrado 9,5 UI, bem pr?ximo a dose tratamento proposto de 10 UI. Quanto ? celularidade do leite (CCS) atrav?s do teste CMT, observou-se rela??o inversa ao aumento das doses suplementares de ocitocina. Em rela??o aos tratamentos 0; 5; 10 e 15UI, a dose de 15 UI resultou em leite com baixa celularidade e melhor qualidade. Maior foi o n?mero de tetos que continham at? 200.000 c?lulas/mL de leite, dentro das normas de produ??o e qualidade determinadas pela Normativa 62. Evidenciou-se o efeito heterog?neo e dose?dependente da ocitocina ex?gena quanto a seus efeitos na produ??o, composi??o e qualidade do leite. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT The objective was to evaluate the application of additional four doses of exogenous oxytocin (0, 5, 10, 15 UI) in removing the residual milk and the production parameters of the milking, residual milk production, production total percentage relative milking total composition and incidence of mastitis through somatic cell counts (CCS). The experiment was conducted in a particular dairy property located in the Francisco S? town, North of Minas Gerais, from February to June 2012. It was used 20 crossbred Holstein-Guzera (3/4 and 7/8), kept at pasture with protein supplementation, clinically healthy, multiparous with lactation from second to fifth, at 60 days postpartum and producing an average of between 7 and 13 kg of milk. The design variables for production and composition were completely randomized with repetition time (nine weeks). Regression was performed on variance analysis. To check the dependence between the prevalence of mastitis and supplemental doses of oxytocin statistical analyzes were performed with chi-square test, and the values of the results considered significant (P <0.01). The volume of milk coming from the milking full showed variance (P <0.01) and quadratic behavior regarding additional doses, drop with doses above 5 IU oxytocin. Milk production residual showed similar behavior, with the dose of 10 IU that best promoted the removal of residual milk. The total milk production was also influenced (P <0.01) by exogenous administration of oxytocin, with higher production above the dose 5UI abruptly decreasing with doses of 10 and 15 IU. The residual milk percentage had the same significance and data distribution quadratically, with 12.3% removal residual milk with the highest dose 15 IU. Residual milk composition was observed significance (P <0.05) only fat, showing o the no significant variance lactose and protein. The residual milk fat content was greater than behaving quadratically when administered 9.5 UI, next to the proposed treatment dose of 10 IU. Milk cellularity (CCS) across the CMT test, observed an inverse relationship to increased supplemental doses of oxytocin. Regarding treatments 0, 5, 10 and 15 IU, the dose of 15 IU resulted a low cellularity and the best milk quality. Greater the number of teats containing up to 200,000 cells / ml milk, within production and quality standards determined by Normative 62. Demonstrating heterogeneous effect and dose-dependent of exogenous oxytocin about the milk production, composition and quality.

Made available in DSpace on 2014-12-17T15:34:45Z (GMT). No. of bitstreams: 1 MiguelASFC_DISSERT.pdf: 664410 bytes, checksum: ea1412fbbc90b4e28d5ec902a12a2ff5 (MD5) Previous issue date: 2011-08-29 / Universidade Federal do Rio Grande do Norte / The objective of this study was to identify DNA polymorphisms at the genes leptin, &#946;-lactoglobulin and pituitary-specific transcription factor in three genetic groups of Holstein x Guzerat dairy cows and investigate the relationship between their genotypes and the composition and quality of milk of dairy cows. Samples were collected in August 2009, being 113 blood samples from lactating crossbred cows and 58 milk samples. For analysis of DNA polymorphisms blood samples were collected, analyzed later in the Genetic Laboratory affiliated to the Zootechny Institute of S?o Paulo and individual milk samples were collected according to standards established by the laboratory of Management Program of Northeast Dairy Herds (PROGEN), at Federal Rural University of Pernambuco (UFRPE) for analysis of milk composition and quality. The characterization of genotypes was performed by PCR-RFLP, for which were designed specific primers for each studied gene and restriction enzymes Kpn2I, HaeIII and HinfI that cut the DNA of the following genes: leptin, &#946;-lactoglobulin and a PIT, respectively. The leptin estimate genotypic frequence were CC 0.112, TT 0.225 and CT 0.661, for &#946;-lactoglobulin were AA 0.136, AB 0.323 and BB 0.539, and for PIT were ++ 0.655, -- 0.311 and +- 0.032. The results show that the population is in Hardy-Weinberg disequilibrium for leptin, &#946;-lactoglobulin and a PIT due to excess of heterozygotes in the population, however, as these genes are associated with the milk production it is considered that the animals have genetic potential for milk production in the Brazilian semi-arid conditions. Through the characterization of the studied herd there were not found implications of the polymorphism of leptin, &#946;-lactoglobulin and PIT in the composition and quality of milk from cows in the different genetic groups 1/2, 3/4 and 7/8 Holstein x Guzerat. Key words: &#946;-lactoglobulin, crossbred cows, leptin, PCR-RFLP, PIT1, semi-arid. / O objetivo do presente estudo ? identificar os polimorfismos de DNA nos genes leptina, &#946;-lactoglobulina e fator de transcri??o pituit?rio espec?fico, em tr?s grupos gen?ticos de vacas leiteiras Holand?s x Guzer? e verificar a rela??o entre seus gen?tipos com a composi??o e qualidade do leite de vacas leiteiras. As amostras foram coletadas em agosto de 2009, sendo 113 amostras de sangue de vacas mesti?as em lacta??o e 58 amostras de leite. Para a an?lise do polimorfismo de DNA foram coletadas amostras de sangue, analisadas posteriormente no Laborat?rio de Gen?tica do Instituto de Zootecnia do Estado de S?o Paulo. As amostras individuais de leite foram coletadas segundo os padr?es estabelecidos pelo laborat?rio do Programa de Gerenciamento de Rebanhos Leiteiros do Nordeste (PROGENE), da Universidade Federal Rural de Pernambuco (UFRPE) para as an?lises de composi??o e qualidade do leite. A caracteriza??o dos gen?tipos foi realizada atrav?s da t?cnica de PCR-RFLP, em que foram utilizados primers espec?ficos para cada gene estudado e enzimas de restri??o Kpn2I, HaeIII e HinfI, promotoras de cortes nos genes leptina, &#946;- lactoglobulina e PIT1, respectivamente. A freq??ncia genot?pica estimada da leptina foi CC 0,112 , TT 0,225 e CT 0,661, da &#946;-lactoglobulina foi AA 0,136, BB 0,323 e AB 0,539 e PIT1 ++ 0,655, -- 0,311 e +- 0,032. Os resultados mostram que a popula??o se encontra em desequil?brio de Hardy-Weinberg para a leptina, &#946;-lactoglobulina e PIT1 devido ao excesso de heterozigotos presentes na popula??o, entretanto, como estes genes est?o associados ? produ??o de leite, considera-se que os animais t?m potencial gen?tico para a produ??o leiteira nas condi??es do semi?rido brasileiro. Atrav?s da caracteriza??o do rebanho estudado n?o foram encontradas implica??es referentes ao polimorfismo da leptina, &#946; lactoglobulina e PIT1 na composi??o e qualidade do leite de vacas nos grupos gen?ticos 1/2, 3/4 e 7/8 Holand?s x Guzer?