Orientador: José Luiz Moraes Vasconcelos / Resumo: Os objetivos foram avaliar o efeito da remoção de bezerros (RB) no desenvolvimento folicular e na indução de ciclicidade e a eficácia do MGA precedendo protocolos de IATF, que utilizam GnRH ou BE, nas taxas de concepção a IATF e gestação. Foram utilizadas 163 vacas paridas em anestro da raça Nelore com 80 ± 29 dias pós-parto e ECC de 3,0 ± 0,29, divididas em 4 grupos: G1: (n=40, controle); G2: (n=42, RB): RB (60 h) 11 dias antes da estação de monta (EM); G3: (n=43, MGA + GnRH): MGA (MGA PREMIX®, 0,5 mg/dia, v.o.) por 10 dias, seguido por RB (60 h), após este período receberam GnRH (CYSTORELIN®, 50 mcg, i.m). Após 6,5 dias, PGF2α (LUTALYSE®, 25 mg, i.m.) que foi seguida por outra RB (54h). Após a RB, todos os animais receberam GnRH e foram inseminados; G4: (n=38, MGA + BE): MGA por 10 dias, seguido por RB (60h), após este período receberam BE (Estrogin , 1,0 mg, i.m.). Após 7 dias, PGF2α que foi seguida por outra RB (54h). Após 24 horas da PGF2α, os animais receberam BE e foram inseminados 30 horas depois. Após a IATF, nos 4 grupos, foi realizado observação de cio e IA (30 d) e por monta natural por mais 32 dias. A ciclicidade, o efeito do MGA e RB no desenvolvimento folicular, as taxas de sincronização, concepção e gestação foram determinados por exames ultra-sonográficos. A variável dias para ficar gestante foi analisada pela curva de sobrevivência, enquanto que as variáveis binomiais e contínuas foram analisadas por regressão logística e pelo GLM do SAS, respectivamente. Foram incluídos no modelo efeito de tratamento, ordem, sexo da cria e suas interações e ECC como co-variável. O MGA foi fornecido, ao G3 e G4, diariamente e os animais ingeriram, em média, 0,99 mg/dia de MGA. O MGA aumentou (P<0,05) o diâmetro do maior folículo (11,2 ± 0,28 vs. 10,3 ± 0,29 mm, respectivamente), que também foi maior (P<0,05) na associação MGA + RB... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objectives of this trial were to evaluate the effects of calf removal (CR) on follicular development and its ability to induce cyclicity and the effects of melengestrol acetate (MGA) preceding TAI protocols, with GnRH or EB on conception and pregnancy rates. Suckled anestrous Nellore cows (n=163) with 80 ± 29 days postpartum and BCS of 3.0 ± 0.29 were assigned into one of four groups: G1: (n=40, control); G2: (n=42, CR): calf removal (60 h) 11 days before the breeding season (BS). G3: (n=43, MGA + GnRH): MGA (MGA PREMIX®, 0.5 mg/day, v.o.) per 10 days, followed by CR (60 h), and GnRH (CYSTORELIN®, 50 mcg, i.m) after CR. Cows received by PGF2α (LUTALYSE®, 25 mg, i.m.) 6.5 days later, and another CR (54h) followed by GnRH and TAI; G4: (n=38, MGA + EB): MGA per 10 days, followed by CR (60h) and injection of EB (Estrogin , 1.0 mg, i.m.) after CR. Cows received PGF2α 7 days later and 24 hours after that, all animals received another EB and were TAI 30 hours later. Calf removal was performed between PGF2α and EB (54 h). After TAI, in all groups, was performed heat detection and AI (30 d) and natural service per more 32 days. Cyclicity status, effect of MGA supplementation and CR on follicular development, synchronization, conception and pregnancy rates were determined by ultrasound. The variable days to pregnancy was analyzed by survival analyses and the binomial and continuous variables were analyzed by logistic regression and GLM of SAS, respectively. The effects of treatment, parity, calf gender and interactions were included in the model, BCS was included as covariable. The MGA was offered to G3 and 4 daily (mixed into the mineral) and the average consumption was 0.99 mg/day. MGA supplementation increased (P<0.05) follicular diameter (11.2 ± 0.28 vs. 10.3 ± 0.29 mm, respectively) Follicular diameter was also increased (P<0.05) when MGA was associated with CR (11.3 ± 0.26 mm)... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2014-06-11T19:27:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2005Bitstream added on 2014-06-13T18:31:49Z : No. of bitstreams: 1 perez_gc_me_botfmvz.pdf: 244671 bytes, checksum: d92a00f6fbf47e3db20740d4e0a01437 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os objetivos foram avaliar o efeito da remoção de bezerros (RB) no desenvolvimento folicular e na indução de ciclicidade e a eficácia do MGA precedendo protocolos de IATF, que utilizam GnRH ou BE, nas taxas de concepção a IATF e gestação. Foram utilizadas 163 vacas paridas em anestro da raça Nelore com 80 ± 29 dias pós-parto e ECC de 3,0 ± 0,29, divididas em 4 grupos: G1: (n=40, controle); G2: (n=42, RB): RB (60 h) 11 dias antes da estação de monta (EM); G3: (n=43, MGA + GnRH): MGA (MGA PREMIX®, 0,5 mg/dia, v.o.) por 10 dias, seguido por RB (60 h), após este período receberam GnRH (CYSTORELIN®, 50 mcg, i.m). Após 6,5 dias, PGF2α (LUTALYSE®, 25 mg, i.m.) que foi seguida por outra RB (54h). Após a RB, todos os animais receberam GnRH e foram inseminados; G4: (n=38, MGA + BE): MGA por 10 dias, seguido por RB (60h), após este período receberam BE (Estrogin , 1,0 mg, i.m.). Após 7 dias, PGF2α que foi seguida por outra RB (54h). Após 24 horas da PGF2α, os animais receberam BE e foram inseminados 30 horas depois. Após a IATF, nos 4 grupos, foi realizado observação de cio e IA (30 d) e por monta natural por mais 32 dias. A ciclicidade, o efeito do MGA e RB no desenvolvimento folicular, as taxas de sincronização, concepção e gestação foram determinados por exames ultra-sonográficos. A variável dias para ficar gestante foi analisada pela curva de sobrevivência, enquanto que as variáveis binomiais e contínuas foram analisadas por regressão logística e pelo GLM do SAS, respectivamente. Foram incluídos no modelo efeito de tratamento, ordem, sexo da cria e suas interações e ECC como co-variável. O MGA foi fornecido, ao G3 e G4, diariamente e os animais ingeriram, em média, 0,99 mg/dia de MGA. O MGA aumentou (P<0,05) o diâmetro do maior folículo (11,2 ± 0,28 vs. 10,3 ± 0,29 mm, respectivamente), que também foi maior (P<0,05) na associação MGA + RB... / The objectives of this trial were to evaluate the effects of calf removal (CR) on follicular development and its ability to induce cyclicity and the effects of melengestrol acetate (MGA) preceding TAI protocols, with GnRH or EB on conception and pregnancy rates. Suckled anestrous Nellore cows (n=163) with 80 ± 29 days postpartum and BCS of 3.0 ± 0.29 were assigned into one of four groups: G1: (n=40, control); G2: (n=42, CR): calf removal (60 h) 11 days before the breeding season (BS). G3: (n=43, MGA + GnRH): MGA (MGA PREMIX®, 0.5 mg/day, v.o.) per 10 days, followed by CR (60 h), and GnRH (CYSTORELIN®, 50 mcg, i.m) after CR. Cows received by PGF2α (LUTALYSE®, 25 mg, i.m.) 6.5 days later, and another CR (54h) followed by GnRH and TAI; G4: (n=38, MGA + EB): MGA per 10 days, followed by CR (60h) and injection of EB (Estrogin , 1.0 mg, i.m.) after CR. Cows received PGF2α 7 days later and 24 hours after that, all animals received another EB and were TAI 30 hours later. Calf removal was performed between PGF2α and EB (54 h). After TAI, in all groups, was performed heat detection and AI (30 d) and natural service per more 32 days. Cyclicity status, effect of MGA supplementation and CR on follicular development, synchronization, conception and pregnancy rates were determined by ultrasound. The variable days to pregnancy was analyzed by survival analyses and the binomial and continuous variables were analyzed by logistic regression and GLM of SAS, respectively. The effects of treatment, parity, calf gender and interactions were included in the model, BCS was included as covariable. The MGA was offered to G3 and 4 daily (mixed into the mineral) and the average consumption was 0.99 mg/day. MGA supplementation increased (P<0.05) follicular diameter (11.2 ± 0.28 vs. 10.3 ± 0.29 mm, respectively) Follicular diameter was also increased (P<0.05) when MGA was associated with CR (11.3 ± 0.26 mm)... (Complete abstract click electronic access below)

Wireless Sensor Networks (WSNs) consist of a large number of resource constrained sensor nodes equipped with various sensing devices which can monitor events in the real world. There are various applications such as environmental monitoring, target tracking forest fire detection, etc., which require clock synchronization among the sensor nodes with certain accuracy. However, a major constraint in the design of clock synchronization protocols in WSNs is that sensor nodes of WSNs have limited energy and computing resources. Clock synchronization process in the WSNs is carried out at each sensor node either synchronously, i.e., periodically during the same real-time interval, which we call synchronization phase, or asynchronously, i.e., independently without worrying about what other nodes are doing for clock synchronization. A disadvantage of asynchronous clock synchronization protocols is that they require the sensor nodes to remain awake all the time. Therefore, they cannot be integrated with any sleep-wakeup scheduling scheme of sensor nodes, which is a major technique to reduce energy consumption in WSNs. On the other hand, synchronous clock synchronization protocols can be easily integrated with the synchronous sleep-wakeup scheduling scheme of sensor nodes, and at the same time, they can provide support to achieve sleep-wakeup scheduling of sensor nodes. Essentially, there are two ways to synchronize the clocks of a WSN, viz. internal clock synchronization and external clock synchronization. The existing approaches to internal clock synchronization in WSNs are mostly hop-by-hop in nature, which is difficult to maintain. There are also many application scenarios where external clock synchronization is the only option to synchronize the clocks of a WSN. Besides, it is also desired that the internal clock synchronization protocol used is fault-tolerant to message loss and node failures. Moreover, when the external source fails or reference node fails, the external clock synchronization protocol should revert back to internal clock synchronization protocol with/without using any reference node. Towards this goal, first we propose three fully distributed synchronous clock synchronization protocols, called Energy Efficient and Fault-tolerant Clock Synchronization (EFCS) protocol, Weighted Average Based Internal Clock Synchronization (WICS) protocol, and Weighted Average Based External Clock Synchronization (WECS) protocol, for WSNs making use of peer-to-peer approach. These three protocols are dynamically interchangeable depending upon the availability of external source or reference nodes. In order to ensure consistency of the synchronization error in the long run, the neighboring nodes need to be synchronized with each other at about the same real time, which requires that the synchronization phases of the neighboring nodes always overlap with each other. To realize this objective, we propose a novel technique of pullback, which ensures that the synchronization phases of the neighboring nodes always overlap. In order to further improve the synchronization accuracy of the EFCS, WICS, and WECS protocol, we have proposed a generic technique which can be applied to any of these protocols, and the improved protocols are referred as IEFCS, IWICS, and IWECS respectively. We then give an argument to show that the synchronization error in the improved protocols is much less than that in the original protocols. We have analyzed these protocols for bounds on synchronization error, and shown that the synchronization error is always upper bounded. We have evaluated the performance of these protocols through simulation and experimental studies, and shown that the synchronization accuracy achieved by these protocols is of the order of a few clock ticks even in very large networks. The proposed protocols make use of estimated drift rate to provide logical time from the physical clock value at any instant and at the same time ensure the monotonicity of logical time even though physical clock is updated at the end of each synchronization phase. We have also proposed an energy aware routing protocol with sleep scheduling, which can be integrated with the proposed clock synchronization protocols to reduce energy consumption in WSNs further.