Optical lucky imaging polarimetry of HL Tau and XZ Tau in the Taurus-Auriga molecular cloud was carried out with the instrument PolCor at the Nordic Optical Telescope (NOT). The results show that in both the V- and R-band HL Tau show centrosymmetric structures of the polarization angle in its northeastern outflow lobe (degree of polarization ~30%). A C-shaped structure is detected which is also present at near-IR wavelengths (Murakawa, 2008), and higher resolution optical images (Stapelfeldt, 1995). The position angle of the outflow is 47.5+-7.5 degrees, which coincides with previous measurements and the core polarization is observed to decrease with wavelength and a few scenarios are reviewed. Measuring the outflow witdh versus distance and wavelength shows that the longer wavelengths scatter deeper within the cavity wall of the outflow. In XZ Tau the binary is partially resolved, it is indicated by an elongated intensity distribution. The polarization of the parental cloud is detected in XZ Tau through the dichroic extinction of starlight. Lucky imaging at the NOT is a great way of increasing the resolution, shifting increases the sharpness by 0.1 asec and selection the sharpest frames can increase the seeing with 0.4 asec, perhaps more during better conditions.

The cattle tick, Rhipicephalus Boophilus microplus (formerly Boophilus microplus), is the most significant parasite of cattle in Australia and threatens the improvement of cattle production in tropical and subtropical countries worldwide. Some cattle breeds of mainly Bos indicus origin develop a strong resistance to infestation with R. B. microplus, while other breeds of mainly Bos taurus origin will succumb to anaemia and ‘tick worry’ in tick-infested pastures. Resistance to cattle tick infestation is primarily manifest against the larval stage and results in the immature tick failing to make a successful attachment and obtain a meal. It is widely accepted that resistance to tick infestation in cattle is immunologically mediated and involves both cell-mediated and humoral immune responses. Previous research has demonstrated a role for the hypersensitivity response in the rejection of larvae from resistant B. taurus cattle. The immune response to R. B. microplus infestation in B. indicus and B. indicus × B. taurus cattle has not been studied in great detail and this thesis aimed to describe those responses of highly tick-resistant cattle that differ from those of tick-susceptible cattle. A pilot trial was conducted using six tick-resistant Brahman heifers (B. indicus) and six tick-susceptible Holstein-Friesian heifers (B. taurus). The animals were artificially infested for several weeks and blood samples obtained weekly for three weeks during the height of infestation, and on one occasion, skin biopsies obtained. It was found that significant differences existed between the two breeds with respect to the percentage of cellular subsets comprising the peripheral blood mononuclear cell (PBMC) population, cytokine expression by peripheral blood leukocytes (PBL), and levels of tick-specific immunoglobulin G1 (IgG1) antibodies measured in the peripheral circulation. These results in combination with whole genome expression analysis of circulating PBL suggested that the B. indicus cattle had developed a stabilised T cell-mediated response to tick infestation evidenced by their cellular profile and leukocyte cytokine spectrum. The B. taurus cattle demonstrated cellular and gene expression profiles consistent with a sustained innate, inflammatory response to infestation, although high tick-specific IgG1 levels suggested that these animals had also developed a T cell response to infestation. Gene expression analyses using quantitative PCR (qPCR) and whole genome expression platforms indicated that the B. taurus cattle elicited an innate inflammatory response in the skin at the site of larval attachment. This was supported by histological examination of the tick-attachment sites. Conversely, the B. indicus cattle appeared to limit the inflammatory response and instead exhibited increased expression of genes involved in wound healing and the structural integrity of the skin. A second trial was conducted using a group of tick-naïve Santa-Gertrudis heifers to eliminate any innate breed differences that may have confounded the results obtained in the pilot trial. Thirty-five animals were obtained from a tick-free region of Australia; thirty animals were artificially infested weekly for thirteen weeks while five animals remained at a tick-free quarantine property to serve as a control group. Following thirteen weeks of tick infestation the animals in this trial exhibited divergent tick-resistance phenotypes and those carrying the lowest and highest numbers of ticks were classified into tick-resistant (n = 6 animals) and tick-susceptible (n = 6 animals) groups, respectively. The larger number of animals in this study and repeated measurements over the course of the trial enabled a detailed analysis of the effect of tick infestation across all animals, and also within the groups identified as highly resistant or highly susceptible. A cell-mediated response to tick-infestation was detected in all tick-infested animals by twenty-one days after the initial infestation, a response which waned towards the end of the trial when the antibody response became more dominant. Similar to the pilot trial, the tick-susceptible animals developed significantly higher levels of tick-specific IgG1 antibodies compared with the tick-resistant group. Some differences were observed between tick-resistant and tick-susceptible animals with respect to the percentage of cellular subsets comprising the PBMC population. Skin biopsies were taken from these animals prior to initial infestation and then at twenty-one days and ninety-one days after the initial infestation and whole genome expression profiles were produced and analysed. At twenty-one days post infestation both tick-resistant and tick-susceptible animals demonstrated an upregulation of genes involved in leukocyte migration and complement activation, suggestive of an inflammatory response. While this response persisted in the tick-susceptible group at ninety-one days post-infestation, it appeared to lessen in the tick-resistant group. A dominant interleukin-8 (IL-8) response was observed in the skin of the tick-susceptible animals at both time points post-infestation that was not observed in the tick-resistant animals. This thesis demonstrates that tick-susceptible animals respond to infestation with R. B. microplus with an apparently non-protective antibody response, and that tick-resistant animals demonstrate different structural responses in the skin at the tick-attachment site compared with the intense inflammatory response observed in tick-susceptible animals. The results presented here suggest that the extreme susceptibility of pure B. taurus and some B. taurus × B. indicus individuals may be due to their heightened ability to recognise and respond to tick antigens introduced into the host via tick saliva during the blood feeding process. These animals’ increased ability to recognise and respond to these proteins may act to set up a chronic state of inflammation that is beneficial to the tick through increased capillary permeability providing a suitable environment for tick feeding and survival.

Submitted by Nathália Faria da Silva (nathaliafsilva.ufv@gmail.com) on 2017-06-07T14:44:18Z No. of bitstreams: 1 texto completo.pdf: 274417 bytes, checksum: c9c56c059a20f3a90aab2b24c081fdc8 (MD5) / Made available in DSpace on 2017-06-07T14:44:18Z (GMT). No. of bitstreams: 1 texto completo.pdf: 274417 bytes, checksum: c9c56c059a20f3a90aab2b24c081fdc8 (MD5) Previous issue date: 2000-12-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O experimento foi conduzido na Fazenda Mundo Novo, município de Brotas - SP, de outubro de 1999 a março de 2000. Os objetivos foram determinar a eficiência do teste da libido realizado em curral, comparando-o ao teste realizado a campo, e relacioná-los à taxa de gestação em estação de monta de 120 dias; testar a tabela de classificação da libido proposta pelo CBRA (1998), para animais da raça Nelore (Bos taurus indicus); propor modificações no teste, e confirmar a relação comportamento sexual/aspectos físicos e morfológicos do sêmen. Foram utilizados 13 touros, todos classificados como aptos à reprodução, avaliados por exame andrológico (exame biométrico dos órgãos sexuais e exame físico e morfológico do sêmen e avaliação clínica), e submetidos ao teste da libido em curral, por 3 h. Destes, 9 touros foram submetidos à avaliação a campo, com proporção touro/vaca 1:33. A cada 21 dias, foi diagnosticada a gestação por ultra-sonografia. Observou-se que, quanto maior o tempo de teste, maiores foram os escores de classificação, sendo que nenhum touro conseguiu efetuar serviço completo dentro dos 10 minutos do teste. Touro classificado como muito bom teve 84,80% de prenhez, porém touros questionáveis tiveram 86,67% e 96,55% ao final da estação. As correlações entre características físicas e morfológicas do sêmen ficaram próximas de zero ou nulas (p>0,05). Os touros reconhecem a fêmea que está em estro pelo ato de cheirar ou lamber o corpo da fêmea, cheirar ou lamber a vulva, seguindo-se ou não o reflexo de Flehmen. A receptividade das fêmeas é testada e os machos efetuam o coito precedido por eventos tais como exposição de pênis, reflexo de monta, tentativa de monta, monta abortada e serviço completo ou cópula. / The experiment was carried out during the period from October 1999 to March 2000 in Fazenda Mundo Novo, Brotas county - SP. The objectives were: to determine the efficiency of the libido test performed in corral, by comparing it to the one accomplished at field, as well as to relate them to the gestation rate over a reproductive period of 120 days; to test the libido classification table proposed by CBRA (1998) for animals of the race Nelore (Bos taurus indicus); to propose modifications for the test and confirm the relationship sexual behavior/ physical and morphologic aspects of the semen. Thirteen bulls were used, all being classified as reproductors and evaluated by breeding soundness evaluation (sexual organ biometric evaluation, and physical and morphologic evaluation of the semen and clinical evaluation), and submitted to the libido test for 3 hours in corral. From these, nine bulls were submitted to the evaluation at field, with a bull/cow proportion of 1:33. At every 21 days, the gestation was diagnosed by ultrasonographic test. It was observed that as longer was the test time as higher were the classification scores, and no bull was able to perform a complete mating service within 10 minutes under testing. The bull classified as xiiivery good showed a conception rate of 84.80%, while the questionable bulls showed 86.67% and 96.55% at the end of the mating period. The correlation among physical and morphologic characteristics of the semen were close to zero or null (p>0.05). The bulls do recognize the female being in oestrous by either the act of smelling or licking the female body or smelling or licking the vulva, following or not the Flehmen reflex. The receptivity of the females is tested and the males perform the coitus preceded by some events such as: penis exhibition, mating reflex, mating attempt, aborted mating) and complete mating service or copulation.

Made available in DSpace on 2014-06-11T19:26:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-04-24Bitstream added on 2014-06-13T18:29:26Z : No. of bitstreams: 1 fonseca_pds_me_jabo.pdf: 310536 bytes, checksum: 07222b519d1969e1951a3e2fbf168660 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Na pecuária de corte, características de crescimento e de carcaça são de grande importância para programas de melhoramento genético. Para acelerar o processo de seleção, os marcadores moleculares auxiliam o estudo dessas características que são influenciadas por efeitos poligênicos. Os genes ACRP30, PPARGC1 e OLR1, foram associados à características ligadas a produção em Bos taurus taurus. Esses genes estão ligados aos processos de sínteses de lipídios, síntese metabólica e acúmulo de gordura no tecido adiposo. Em nosso estudo, foram genotipados 639 animais, através da técnica de PCR-RFLP, para os genes ACRP30/BsrI, PPARGC1/NheI e OLR/PstI, onde foram detectados polimorfismos correspondentes aos sítios de restrição. Para as linhas de seleção Controle (NeC), Seleção(NeS) e Tradição(NeT) em bovinos Nelore, do Instituto de Zootecnia de Sertãozinho-IZ, foram feitas associações com características de peso ao nascer, peso no desmame, peso ao sobreano das fêmeas, altura ao sobreano da garupa das fêmeas, peso ao sobreano dos machos, altura ao sobreano da garupa dos machos, área de olho de lombo, espessura de gordura da garupa, espessura de gordura subcutânea e polimorfismos nos genes estudados, utilizado o PROC MIXED, do programa SAS/STAT 9.1.3. para análises de associações e Teste de Fisher para diferenciação entre populações do programa Genepop. A correção dos testes de hipóteses para comparações múltiplas foi feita pelo método de Bonferroni Os genótipos apresentados foram associados com as características de crescimento e carcaça, não apresentando efeitos significativos na população estudada / In beef cattle production, growth and carcass traits are of great importance for animal breeding programs. To speed up the selection process, molecular markers help to study traits that are influenced by polygenic effects. The ACRP30, PPARGC1 and OLR1 genes were validated in some studies for traits related to production in Bos taurus. This genes are linked to processes of lipids and metabolic synthesis and accumulation of fat in the adipose tissue. In this study, 639 animals were genotyped by PCR-RFLP, for genes ACRP30/BsrI, PPARGC1/NheI and OLR/PstI, where polymorphisms were detected, corresponding to the restriction sites. For selection lines Control (NeC), Selection (NeS) and Tradition (NeT) in Nellore cattle, from the Institute of Zootecnia from Sertãozinho – IZ, associations were made with polymorphisms in the studied genes and the trais birth weight, weaning weight, yearling weight, yearling rump height, ribeye area, rump fat thickness and subcutaneous fat thickness, using the PROC MIXED from SAS/STAT 9.1.3. program for association analysis, and Fisher Test for population differentiation from Genepop program. The correctness of the hypothesis tests for multiple comparisons was made using the Bonferroni. The genotypes found were associated with the with growth and carcass traits but showed no significant effects on the studied population

Made available in DSpace on 2014-06-11T19:26:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-16Bitstream added on 2014-06-13T19:33:18Z : No. of bitstreams: 1 camargo_gmf_me_jabo.pdf: 1327591 bytes, checksum: 61ead412f84b2a4805a3817c99b641d0 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Na bovinocultura de corte, a probabilidade de prenhez precoce é uma característica de grande relevância devido ao alto valor econômico associado. Essa característica apresenta elevados valores de herdabilidade e há possibilidade de ganho genético por seleção. Todavia, a característica é de limiar com distribuição binária e suposições são feitas no intuito de analisá-la. Marcadores moleculares podem vir a auxiliar na avaliação genética desses animais, além de promover diminuição do intervalo de gerações. A proteína JY-1 é uma proteína específica dos oócitos de bovinos e que atua nas células da granulosa em co-ação com o LH e no desenvolvimento embrionário inicial podendo influenciar a chance de prenhez. Marcadores moleculares foram usados para estudar o gene JY-1 e foram encontrados sete polimorfismos do tipo SNP no éxon 3. As posições dos SNPs no referido éxon e as substituições são: 163 (T/C), 281(T/C), 321(T/C), 532(T/C), 652 (A/G), 679(T/C) e 722 (G/C) (Genbank: JN592587 JF262042.2). O SNP 163 está em região codificante e causa substituição de uma prolina por uma leucina. Os demais SNPs estão em região 3’UTR. Os SNPs 163, 281, 321 e 679 foram genotipados em 297 novilhas da raça Nelore. Os SNPs 163, 321 e 679 estavam em desequilíbrio de ligação entre si e em equilíbrio com o 281. Os genótipos não apresentaram correlação com probabilidade de prenhez precoce e características de crescimento (P<0,05) / In beef cattle production, the sexual precocity is important because of the high associated economic value. The heritability values are high which permits genetic gain by selection. However, it is a threshold trait with binary distribution and suppositions are done in order to analyze it. So, molecular markers may auxiliary the genetic evaluation of these animals and reduce the generation interval. The JY-1 protein is an oocyte specific cattle protein and acts in granulose cells with LH and also in early embryo development and may influence sexual precocity. The gene of the protein was analyzed by molecular markers and seven SNP polymorphisms were found in exon 3. The SNPs positions in the exon and the substitutions were: 163 (T/C), 281(T/C), 321(T/C), 532(T/C), 652 (A/G), 679(T/C) e 722 (G/C) (Genbank: JN592587 JF262042.2) The SNP 163 is in CDS region and it causes a substitution of a prolin by a leucin. The others SNPs are in 3’UTR region. The SNPs 163, 281, 321 and 679 were genotyped in 297 Nellore heifers. The SNPs 163, 321 and 679 were in linkage disequilibrium among them and the SNP 281 was in equilibrium. The genotypes did not show correlation with sexual precocity and growth traits (P<0.05)

Made available in DSpace on 2014-06-11T19:29:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-17Bitstream added on 2014-06-13T20:59:08Z : No. of bitstreams: 1 arantes_fcc_me_araiq.pdf: 1216127 bytes, checksum: 3965b43021ae3aaf6af565984dff1085 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho envolve a síntese e caracterização espectroscópica de compostos mononucleares de Pd(II) obtidos a partir da interação entre o precursor [PdCl2(MeCN)2], tiouréias N-substituídas (metu = N-metiltiouréia; ftu = N-feniltiouréia) e trifenilfosfina (PPh3), na presença dos íons SCN- e Br - . A reação entre [PdCl2(MeCN)2], tiouréias N-substituídas e a trifenilfosfina, na razão molar de 1:1:1, respectivamente, forma os complexos [PdCl2(Rtu)(PPh3)] (Rtu = metu, ftu). Os complexos [PdX2(PPh3)(Rtu)] (Rtu = metu, ftu; X- = SCN, Br) foram preparados a partir da interação entre o respectivo cloro-complexo e sais KX, razão molar de 1:2, respectivamente. A coordenação das tiouréias N-substituídas pelo átomo de enxofre na série [PdX2(PPh3)(Rtu)] (X- = Cl, SCN, Br) foi evidenciada pela espectroscopia no IV pelo deslocamento da banda C-NHR para freqüências mais altas em relação a do ligante livre, indicando o fortalecimento da ligação CN. Os espectros de RMN também mostram a coordenação via átomo de S pelo deslocamento do sinal de 13 C do grupo tionila para regiões de campo alto quando comparado ao do ligante Rtu, evidenciando o enfraquecimento da ligação CS após a coordenação. Já a presença da trifenilfosfina foi sugerida pelo aparecimento das suas bandas no IV típicas em 1098 cm-1 (CH), 693 cm-1 (anel) e 520 cm-1 (modo y). As curvas TG-DTA obtidas mostram que os complexos se decompõem em Pd0 sem formar uma fase estável de sulfeto metálico. A reação entre a N,N´-difeniltiouréia e íons Cu(II) também foi investigada neste trabalho. O composto obtido de fórmula [CuCl(dftu)2]n foi caracterizado pelas espectroscopias no IV e de RMN de 1 H e 13 C{1 H}. A atividade inibitória dos compostos dftu e [CuCl(dftu)2]n frente ao crescimento dos fungos Candida albicans, Candida krusei, Candida parapsilosis e Candida neoformans também foi avaliada. / This work deals with the syntheses, spectroscopic characterization of Pd(II) mononuclear compounds obtained from the interaction among [PdCl2(MeCN)2] precursor, N-substituted thioureas (metu = N-methylthiourea; ftu = N-phenylthiourea) and triphenylphosphine (PPh3), in the presence of SCN- e Br - ions. The reaction among [PdCl2(MeCN)2], N-substituted thioureas and triphenylphosphine, in the molar ratio 1:1:1, respectively, yield the complexes [PdCl2(PPh3)(Rtu)] (Rtu = metu, ftu). The compounds [PdX2(Rtu)(PPh3)] (Rtu = metu, ftu; X- = SCN, Br) were prepared from the interaction between the appropriate chloro-complex and KX salts, in molar ratio 1:2, respectively. The coordination of N-substituted thioureas through sulfur atom in the serie [PdX2(PPh3) (Rtu)] (X- = Cl, SCN, Br) was inferred by IR spectroscopy by the shift of C-NHR band to higher frequencies than those of the free ligand, indicating an increasing in the CS bond strenght. NMR spectra also showed the S-coordination by the upfield shift of the 13 C signal of thionil group when compared to those of the free ligand, suggesting the weakening of the CS bond after coordination. The presence of triphenylphosphine was confirmed by the appearance of its typical bands at 1098 cm-1 (CH), 693 cm-1 (ring) e 520 cm-1 (y). TG-DTA curves showed that Pd(II) compounds decompose into Pd0 without the formation of a stable intermediate of metal sulphide. The reaction between N,N´-diphenylthiourea and Cu(II) íons was also investigated in this work. The compound [CuCl(dftu)2]n was characterized by IR and 1 H and 13 C{1 H} NMR spectroscopies. The inhibitory activity of the compounds dftu e [CuCl(dftu)2]n towards the growth of Candida albicans, Candida krusei, Candida parapsilosis e Candida neoformans was also evaluated.

O objetivo deste estudo foi determinar os efeitos da aplicação de hCG no quarto dia após a inseminação a tempo fixo (IATF) sobre o tamanho do corpo lúteo (CL) existente, a indução de CL acessórios, a concentração de progesterona (P4) sérica e taxa de prenhez de vacas de corte em lactação. Nos três experimentos, vacas de corte multíparas (n=569), cruza Bos taurus, com período pós-parto entre 45 e 70 dias, foram sincronizadas com a administração de 2mg de benzoato de estradiol i.m. e a inserção de um dispositivo intravaginal contendo 0,750g de P4 (Dia -9). Sete dias após, administraram-se 150 μg de D-cloprostenol e 0,5 mg de cipionato de estradiol, i.m., no momento da retirada do dispositivo (Dia -2). Sessenta vacas de corte em lactação foram divididas aleatoriamente em dois grupos: hCG (n=30) tratadas com 1500UI i.m. de hCG e Controle (n=30) injetadas com 1,5 mL de solução salina i.m. no dia 4 depois do estro (Dia 0). Realizaram-se coletas sanguíneas dos animais para mensuração da concentração sérica de P4 nos Dias 4, 7, 10 e 14 do ciclo estral. Para acompanhamento da dinâmica ovariana, sessenta animais foram divididos aleatoriamente nos grupos hCG (n=30) ou Controle (n=30) e receberam o mesmo protocolo hormonal como citado anteriormente. No Dia 0, os ovários foram examinados por ultrassonografia transretal para determinar o diâmetro do folículo ovulatório; no Dia 4, o diâmetro do FD e presença do CL e no Dia 7 para mensurar a área luteal do CL e a presença de CL acessório. Quinhentas e sessenta e nove vacas (hCG, n= 269 e Controle, n= 300) foram inseminadas a tempo fixo 52-56 horas depois da retirada dos implantes de P4 e tratadas no Dia 4, conforme o protocolo descrito. O diagnóstico de prenhez foi realizado por ultrassonografia 30 dias após a IATF. Os resultados observados, mostraram que vacas tratadas com hCG no Dia 4 apresentaram maiores concentrações sérica de P4 no Dia 7, comparadas com as do grupo Controle (4,45 vs. 3,37ng/mL, respectivamente; p<0,05), mas níveis semelhantes de P4 nos Dias 10 e 14. Os animais do grupo hCG apresentaram CL com maior (p<0,01) área luteal no Dia 7, em relação ao grupo Controle (3,52 cm² vs. 2,66 cm², respectivamente) e uma incidência de 29,6 % de indução da ovulação do FD presente no Dia 4. Observou-se uma taxa de prenhez maior (p=0,071) no grupo tratado com hCG (53,9%) comparando-se com as vacas não tratadas (46,3%). Conclui-se que a administração de hCG no quarto dia do ciclo estral promove o aumento da área do CL, melhora função luteal, pode induzir a formação de CL acessório e tende a aumentar a taxa de prenhez de vacas de corte em lactação. / The aim of this study was to determine the effects of injection of hCG on the fourth day after the TAI on the size of the existing corpus luteum (CL), the induction of CL accessories, the concentration of progesterone (P4) levels and the possibility of increasing the rate of pregnancy of lactating beef cows subjected to synchronization of estrus and ovulation. Multiparous beef cows (n= 569), Bos taurus crossbreed with postpartum between 45 and 70 days were synchronized by administration of 2mg of estradiol benzoate im and the insertion of an intravaginal device containing 0,750g of P4 (Day -9). Seven days later, were administered 150mg of D- cloprostenol 0.5 mg of estradiol cypionate, im, at the time of device removal (Day -2). Sixty lactating beef cows were randomly divided into two groups: hCG (n= 30) treated with im 1500UI hCG and Control (n= 30) injected with 1.5 ml of saline im on day 4 after estrus (Day 0). There were blood collections of animals for measurement by radioimmunoassay of serum P4 on Days 4, 7, 10 and 14 of the estrous cycle. To evaluate the ovarian dinamics, sixty animals (hCG, n= 30 and Control, n = 30) received the same hormonal protocol and were uniformly distributed into groups according to the diameter of the ovulatory follicles on day 0 (estrus). On Day 0, the ovaries were examined by transrectal ultrasonography to determine the diameter of the ovulatory follicle, on Day 4, the diameter of the dominant follicle (DF) and the presence of CL on Day 7 to measure the area of the luteal CL and the presence of accessory CL. Five hundred and sixty-nine cows (hCG, n= 269 and Control, n= 300) were inseminated at a fixed time 52 to 56 hours after removal of the P4 devices treated on Day 4, according to the protocol described previously. The diagnosis of pregnancy were performed by ultrasonography 30 days after TAI. The results demonstrate that cows treated with hCG on Day 4 showed higher serum concentrations of P4 on Day 7, compared with the control group (4.45 vs. 3.37ng/mL, respectively, (p<0.05), but similar levels of P4 on Days 10 and 14. The animals of hCG group had greater (p<0,01) luteal area on Day 7, compared to the Control group (3.52cm² vs. 2.66cm², respectively) and a 29.6% incidence of induction DF ovulation present on Day 4. We observed a higher rate of pregnancy (p= 0.071) in the group treated with hCG (53.9%) comparing with untreated cows (46.3%). We conclude that administration of hCG on the fourth day of the estrous cycle increase the CL area, improves luteal function, can induce the formation of accessory CL and tends to increase the pregnancy rate of lactating beef cows.

O objetivo deste estudo foi determinar os efeitos da aplicação de hCG no quarto dia após a inseminação a tempo fixo (IATF) sobre o tamanho do corpo lúteo (CL) existente, a indução de CL acessórios, a concentração de progesterona (P4) sérica e taxa de prenhez de vacas de corte em lactação. Nos três experimentos, vacas de corte multíparas (n=569), cruza Bos taurus, com período pós-parto entre 45 e 70 dias, foram sincronizadas com a administração de 2mg de benzoato de estradiol i.m. e a inserção de um dispositivo intravaginal contendo 0,750g de P4 (Dia -9). Sete dias após, administraram-se 150 μg de D-cloprostenol e 0,5 mg de cipionato de estradiol, i.m., no momento da retirada do dispositivo (Dia -2). Sessenta vacas de corte em lactação foram divididas aleatoriamente em dois grupos: hCG (n=30) tratadas com 1500UI i.m. de hCG e Controle (n=30) injetadas com 1,5 mL de solução salina i.m. no dia 4 depois do estro (Dia 0). Realizaram-se coletas sanguíneas dos animais para mensuração da concentração sérica de P4 nos Dias 4, 7, 10 e 14 do ciclo estral. Para acompanhamento da dinâmica ovariana, sessenta animais foram divididos aleatoriamente nos grupos hCG (n=30) ou Controle (n=30) e receberam o mesmo protocolo hormonal como citado anteriormente. No Dia 0, os ovários foram examinados por ultrassonografia transretal para determinar o diâmetro do folículo ovulatório; no Dia 4, o diâmetro do FD e presença do CL e no Dia 7 para mensurar a área luteal do CL e a presença de CL acessório. Quinhentas e sessenta e nove vacas (hCG, n= 269 e Controle, n= 300) foram inseminadas a tempo fixo 52-56 horas depois da retirada dos implantes de P4 e tratadas no Dia 4, conforme o protocolo descrito. O diagnóstico de prenhez foi realizado por ultrassonografia 30 dias após a IATF. Os resultados observados, mostraram que vacas tratadas com hCG no Dia 4 apresentaram maiores concentrações sérica de P4 no Dia 7, comparadas com as do grupo Controle (4,45 vs. 3,37ng/mL, respectivamente; p<0,05), mas níveis semelhantes de P4 nos Dias 10 e 14. Os animais do grupo hCG apresentaram CL com maior (p<0,01) área luteal no Dia 7, em relação ao grupo Controle (3,52 cm² vs. 2,66 cm², respectivamente) e uma incidência de 29,6 % de indução da ovulação do FD presente no Dia 4. Observou-se uma taxa de prenhez maior (p=0,071) no grupo tratado com hCG (53,9%) comparando-se com as vacas não tratadas (46,3%). Conclui-se que a administração de hCG no quarto dia do ciclo estral promove o aumento da área do CL, melhora função luteal, pode induzir a formação de CL acessório e tende a aumentar a taxa de prenhez de vacas de corte em lactação. / The aim of this study was to determine the effects of injection of hCG on the fourth day after the TAI on the size of the existing corpus luteum (CL), the induction of CL accessories, the concentration of progesterone (P4) levels and the possibility of increasing the rate of pregnancy of lactating beef cows subjected to synchronization of estrus and ovulation. Multiparous beef cows (n= 569), Bos taurus crossbreed with postpartum between 45 and 70 days were synchronized by administration of 2mg of estradiol benzoate im and the insertion of an intravaginal device containing 0,750g of P4 (Day -9). Seven days later, were administered 150mg of D- cloprostenol 0.5 mg of estradiol cypionate, im, at the time of device removal (Day -2). Sixty lactating beef cows were randomly divided into two groups: hCG (n= 30) treated with im 1500UI hCG and Control (n= 30) injected with 1.5 ml of saline im on day 4 after estrus (Day 0). There were blood collections of animals for measurement by radioimmunoassay of serum P4 on Days 4, 7, 10 and 14 of the estrous cycle. To evaluate the ovarian dinamics, sixty animals (hCG, n= 30 and Control, n = 30) received the same hormonal protocol and were uniformly distributed into groups according to the diameter of the ovulatory follicles on day 0 (estrus). On Day 0, the ovaries were examined by transrectal ultrasonography to determine the diameter of the ovulatory follicle, on Day 4, the diameter of the dominant follicle (DF) and the presence of CL on Day 7 to measure the area of the luteal CL and the presence of accessory CL. Five hundred and sixty-nine cows (hCG, n= 269 and Control, n= 300) were inseminated at a fixed time 52 to 56 hours after removal of the P4 devices treated on Day 4, according to the protocol described previously. The diagnosis of pregnancy were performed by ultrasonography 30 days after TAI. The results demonstrate that cows treated with hCG on Day 4 showed higher serum concentrations of P4 on Day 7, compared with the control group (4.45 vs. 3.37ng/mL, respectively, (p<0.05), but similar levels of P4 on Days 10 and 14. The animals of hCG group had greater (p<0,01) luteal area on Day 7, compared to the Control group (3.52cm² vs. 2.66cm², respectively) and a 29.6% incidence of induction DF ovulation present on Day 4. We observed a higher rate of pregnancy (p= 0.071) in the group treated with hCG (53.9%) comparing with untreated cows (46.3%). We conclude that administration of hCG on the fourth day of the estrous cycle increase the CL area, improves luteal function, can induce the formation of accessory CL and tends to increase the pregnancy rate of lactating beef cows.

A espécie Bos indicus, particularmente a raça Nelore, é grande maioria no rebanho bovino da região acima do trópico no Brasil. Embora a habilidade desses animais em resistir às doenças parasitárias, condições climáticas e pastagens de baixa qualidade enalteçam a utilização em larga escala desta raça, estes animais não são considerados bons conversores de alimento e, conseqüentemente, precoces em comparação aos seus homólogos Bos taurus. Durante a formação das raças zebuínas brasileiras, houve uma participação das linhas maternas de Bos taurus, que pode ser demonstrada pela contribuição majoritária do genoma mitocondrial desta subespécie. Embora em escala muito menor, estima-se que exista também uma participação destas linhas maternas no genoma nuclear. O objetivo deste trabalho foi iniciar os estudos para estimar esta participação. Para os estudos foram utilizados 104 animais da raça Nelore e 8 animais de diferentes raças européias. Cinco regiões do DNA que produzem fragmentos microssatélites taurus/indicus específicos (HEL1, HEL9, ETH225, ILSTS005 e INRA063) foram amplificadas com a utilização de primers marcados com sondas fluorescentes. Os fragmentos foram submetidos à eletroforese em gel de poliacrilamida desnaturante 6% e visualizados após excitação com laser. No total foram encontrados 23 alelos para os microssatélites analisados o que representa uma média de 4,6±1,82 alelos por locus. Amplificou-se também uma região do DNA satélite 1711b que posteriormente foi digerida com a enzima de restrição Msp I. Verificou-se a existência de três possíveis genótipos entre os animais Nelore mtDNA Bos taurus e mtDNA Bos indicus. Os animais europeus analisados apresentaram sempre o mesmo padrão de restrição. A comparação dos componentes de variância do tamanho dos alelos intra e inter população usando os fragmentos microssatélites permitem a separação dos animais Bos taurus dos animais Nelore, mas não dos Nelore de origem materna distinta. No entanto, a freqüência de alelos indicus específicos nos microssatélites e de padrões de digestão do DNA satélite também indicus específicos sugerem uma participação da ordem de aproximadamente 6% do genoma taurus na população de gado Nelore. / Bos indicus specie, especially Nellore breed is responsible for the majority of Brazilian tropical herd. These animals are notably capable to endure parasite infection as well as hot weather and low quality feed. In one hand this qualities suggest the large scale application of this breed, but in other hand this same breed is well characterized as bad food converter and consequently far from having good precocity status compared with its Bos taurus homologues. It has been reported a matrilineal European participation in Zebu cattle since its introduction in American lands. This hybridization is confirmed by the majority contribution of Bos taurus mtDNA in these animals. Although in a much lower frequency, we hypothesize a Bos taurus cow participation in nuclei genome. The main aim of this work was to give the firsts steps towards the estimation of this participation. A total of 104 Nellore and 8 animals of different European breeds were used for DNA analysis. Five microsatellites fragments (HEL1, HEL9, ETH225, ILSTS005 e INRA063) were amplified applying primers with fluorescent dye. Amplified fragments were used in 6% polyacrilamide electrophoresis and visualized after laser excitation. Overall 23 alleles were detected averaging 4.6±1,82/locus. Variance components of microsatellites allele size comparisons allowed the formation of two clusters separating both subspecies. No significant variation was observed between Nellore with different maternal origins. A satellite 1711b DNA was also amplified and digested with the restriction enzyme Msp I. Three possible genotypes were identified in Nellore animals harboring B. taurus and B. indicus mtDNA. European originated animals always showed the same restriction pattern. Finally B. indicus specific microsatellite allele and satellite 1711b digestion patterns frequency allowed the estimation of 6% of B. taurus contribution in purebred Nellore. These results are discussed in terms of application in cattle genetic improvement.

Orientador: Josineudson Augusto II de Vasconcelos Silva / Resumo: A raça Gir (Bos indicus) é importante recurso genético para produção de carne e leite no Brasil e em países tropicais. Estudos genômicos entre populações são de interesse para identificar regiões genômicas importantes e aplicar na seleção de caraterísticas de produção. As corridas de homozigose (ROH) são regiões homozigotas contíguas do genoma, utilizadas na identificação de genes associados a características de interesse econômico, bem como na obtenção dos coeficientes de endogamia. A interação genótipo ambiente (IGA), também representa papel importante no estudo de populações de bovinos e na seleção dos melhores reprodutores para os diferentes ambientes. Com isto, os objetivos do presente estudo foram analisar o comprimento e a distribuição das ilhas ROH do genoma, com identificação dos gene presentes, além de avaliar a acurácia da imputação utilizando diferentes painéis comerciais e a interação genótipo ambiente da produção de leite em bovinos da raça Gir do Brasil e Colômbia. Na avaliação das ilhas ROH foram utilizados dados genotípicos de 173 animais selecionados para produção de carne e 291 animais selecionados para produção leiteira e obtidos os resultados via programa Plink. Análise da acurácia utilizando diferentes painéis de SNPs (GGP Bovine 30K, GGP indicus 35K e HD 777K) de 464 animais do Brasil e da Colômbia foram avaliados e os resultados comparados via correlação simples (CS) e taxa de concordância (CR). Na análise da IGA foi utilizado modelo de norma de reação... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Gir breed (Bos indicus) is an important genetic resource for meat and milk production in Brazil and in tropical countries. Genomic studies between populations are of interest to identify important genomic regions and apply in the selection of production traits. Runs of Homozygosity (ROH) are contiguous homozygous regions of the genome, used to identify genes associated with characteristics of economic interest, as well as to obtain inbreeding coefficients. The environment genotype (IGA) interaction also plays an important role in the study of bovine populations and in the selection of the best breeders for different environments. Thus, the objectives of the present study were to analyze the length and distribution of the ROH islands of the genome, with identification of the present genes, in addition to assessing the accuracy of imputation using different commercial panels and the environment genotype interaction of milk production in cattle of the Gir breed from Brazil and Colombia. In the evaluation of the ROH islands, genotypic data from 173 animals selected for beef production and 291 animals selected for milk production were used and the results were obtained through the Plink program. Accuracy analysis using different SNP panels (GGP Bovine 30K, GGP indicus 35K and HD 777K) from 464 animals from Brazil and Colombia were evaluated and the results were compared using simple correlation (CS) and concordance rate (CR). The IGA analysis used a bi-traits reaction standard... (Complete abstract click electronic access below) / Doutor