The work deals with the analysis of some conditions to increase the level of piglets in factory farms. In addition to the genetic material used in crossing the farm, there is really important material support: good nutrition, breeding environment and nursing care. All these requirements were fullfilled in evaulated plant. In the breeding herd, were revealed a significant effect of early estrus and early pregnancy rate in the interval weaning of piglets. The obtained data showed that the percentage is not significantly different farrowing in sows and gilts. The number of live born piglets is no significant difference in sows and gilts. That's why is advantagous to continuously include gilts in basic herd and early replacement of saws according to their health status and number of past litters. Return breeding of sows should be at the annual breeding 23 to 25 piglets per sow.

Made available in DSpace on 2014-06-11T19:29:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-23Bitstream added on 2014-06-13T20:59:32Z : No. of bitstreams: 1 paula_mc_me_botfmvz.pdf: 465421 bytes, checksum: d4f7523bab03de870773e810dfc43208 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A cadela apresenta particularidades no ciclo estral e, o conhecimento de tais características é fundamental para a implantação de técnicas de reprodução assistida. A indução do estro é uma importante ferramenta tanto em pesquisas quanto no manejo reprodutivo de canis. Portanto, o presente trabalho utilizou um agonista da dopamina – cabergolina – 105 -120 dias após o final do estro na dose de 5μg/Kg por no máximo 15 dias ou até a fêmea apresentar sinais de estro, a fim de induzir e acompanhar os estros, espontâneo e induzido em cadelas, desde o início do proestro até o final do estro. As fêmeas foram divididas em 2 grupos: controle (espontâneo) e experimental (induzido). Amostras de sangue para a dosagem de progesterona e esfregaço vaginal foram coletadas a cada 2 dias, além de, observação dos sinais clínicos e comportamentais. Todas as 5 fêmeas do grupo experimental responderam ao tratamento com cabergolina em média após 42,6 dias, sendo que em 2 fêmeas essa resposta foi mais rápida e ambas apresentaram sinais de estro antes do final do tratamento. Ademais, o Intervalo Interestral (IIE) foi menor nas fêmeas do grupo experimental, 159 ± 15.01, em relação às do grupo controle, 169 ± 13.43 dias. O perfil da progesterona e o padrão citológico não apresentaram diferenças entre os grupos estudados bem como os sinais clínicos e comportamentais. Em suma, a cabergolina pode ser empregada como agente indutor do estro na cadela, a fim de diminuir o IIE e facilitar o manejo reprodutivo. / The bitch presents certain peculiarities in her estrus cycle that makes the knowing of such differences a sine qua non condition to the ones that want to implement assisted reproduction techniques. The estrus induction is an important tool not only for researches but also for kennels’ reproductive managements. Hence this present study has used the cabergoline, which is a dopamine agonist, from 105 to 120 days after the end of the estrus at 5μg/Kg until the bitch presented estrus signs (maximum of 15 days of injection). Both spontaneous and induced estruses were observed from the beginning of proestrus until the end of estrus. Bitches were divided into 2 groups: control (spontaneous) and experimental (induced). Blood samples to check progesterone levels and vaginal smears were taken every 2 days, and clinical signs and behavioral changes were also observed and taken into consideration. All 5 females from the experimental group responded to the cabergoline treatment (42,6 days), but 2 bitches responded earlier than that and both presented estrus signs before the end of the treatment. Not only that but also the interestral interval (IEI) was shorter for the bitches in the experimental group, 159 ± 15,01, if compared to the control group, 169 ± 13,43 days. The progesterone profile and the cytological standard did not present any difference among the studied groups, and so happened to the clinical and behavioral signs. To sum up, cabergoline can be used as a tool to induce estrus in bitches in order to reduce the IEI and facilitate the reproductive management.

Made available in DSpace on 2014-06-11T19:29:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-12Bitstream added on 2014-06-13T20:38:45Z : No. of bitstreams: 1 iwamura_j_me_botfmvz.pdf: 434455 bytes, checksum: ddccafed0c8a8b01cf8b0ac42dc74c37 (MD5) / Universidade Estadual Paulista (UNESP) / Objetivou-se avaliar protocolos de sincronização do estro e da ovulação, com esponja impregnada de acetato de medroxiprogesterona (MAP), mantida por diferentes períodos (G – grupo - I e GII – 6 dias, GIII e GIV – 9 dias e GV e GVI – 13 dias) e associado a duas dosagens de gonadotrofina coriônica eqüina (eCG, GII, GIV e GVI – 350UI e GIII, GV e GVI – 500UI). Assim, ovelhas da raça Santa Inês (n=53) receberam pessários intra-vaginais de MAP, com administração do eCG no momento da retirada. A inseminação foi realizada 48 horas após a retirada dos pessários, pela via cervical superficial, empregando-se sêmen fresco. A taxa de gestação foi determinada através da ultra-sonografia 60 dias após a inseminação. A progesterona plasmática foi determinada através de radiomunoensaio. As taxas de estro e prenhez nos grupos GI, GII, GIII, GIV, GV e GVI foram, respectivamente, 90% e 30 %; 100% e 33,3%; 100% e 33,3; 20% e 20%; 100% e 37,50 % e 80% e 40%. Foi observada diferença estatística quanto ao número de ovelhas em estro (P<0,05), mas a taxa de prenhez entre os grupos foram semelhantes. No momento da retirada do pessário, a concentração de progesterona foi superior (P<0,05) para os grupos de nove dias (GII e GV). Conforme os resultados obtidos neste estudo, conclui-se que a dosagem de eCG não influenciou os resultados obtidos e que o protocolo de curta duração pode ser utilizado com eficácia semelhante ao de longa duração, para a sincronização de estro das ovelhas. / The aim was to analyze the estrous and ovulation synchronization´s protocols, with medroxyprogesterone acetate (MAP), maintained by different periods (G – group - I and GII - 6 days, GIII and GIV - 9 days and GV and GVI - 13 days) and linked to two doses of equine chorionic gonadotropin (eCG, GII, GIV and GVI - 350UI and GIII, GV and GVI- 500UI). Thus, Santa Ines sheep breed (n=53) received intravaginal pessaries of MAP, with administration of eCG at the time of withdrawal. The insemination was performed 48 hours after the withdrawal of pessaries, through superficial cervical, using fresh sperm. The pregnancy rate was determined by ultrasound 60 days after insemination. The progesterone plasma was determined by radiomunoensaio. The rate of estrus and pregnancy in groups GI, GII, GIII, GIV, GV and GVI were respectively, 90% and 30%; 100% and 33.3%; 100% and 33.3; 20% and 20%; 100% and 37.50% and 80% and 40%. The number of ewes in estrus was a statistical difference in (P< 0.05) , but the pregnancy rates between the groups were similar. At the time of withdrawal of the pessaries, the concentration of progesterone was higher (P <0.05) for groups of nine days (GII and GV). It was concluded that the strength of eCG did not influence the results and that the protocol of short duration can be used with similar efficacy to the long-term for the synchronization of estrus of sheep.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Avaliou-se a eficiÃncia de dois protocolos de induÃÃo e sincronizaÃÃo do estro e da ovulaÃÃo (âCIDR-Bâ âOVSYNCHâ) em 90 novilhas acÃclicas da raÃa Girolanda. Os animais foram distribuÃdos em trÃs grupos, onde o primeiro (n=30) foi submetido ao protocolo âOVSYNCHâ, que consiste na aplicaÃÃo intramuscular (IM) de 1,0ml de GnRH, sete dias depois 2,0ml de prostaglandina F2a (PGF2a), 48h depois mais 1,0ml de GnRH e IATF 16h apÃs a segunda dose de GnRH. O segundo grupo (n=30) foi submetido ao tocolo âCIDR-Bâ, que consiste na introduÃÃo do implante intravaginal âCIDR-Bâ juntamente com a aplicaÃÃo IM de 2,0ml de benzoato de estradiol (BE), apÃs 8 dias à feita a remoÃÃo do âCIDR-Bâ e a aplicaÃÃo IM de 500UI de gonadotrofina sÃrica da Ãgua prenhe (PMSG) e 2,0ml de PGF2a, 24h apÃs à feita mais uma aplicaÃÃo IM de BE e IATF 30h depois desta aplicaÃÃo, ou seja, 54h apÃs a remoÃÃo do âCIDR-Bâ. O rceiro grupo (n=30), grupo controle, nÃo foi submetido a tratamento hormonal. Os diagnÃsticos de gestaÃÃes foram feitos 35 dias apÃs a primeira, segunda e terceira nseminaÃÃes artificiais (IA) por meio de ultra-sonografia (US). TambÃm foi avaliado o custo/benefÃcio de cada protocolo. O tratamento âCIDRBâ mostrou-se mais eficiente em primeira IA (p<0,05), assemelhando-se ao grupo controle com taxas de concepÃÃo e prenhez de 60 e 50%, respectivamente, demonstrando ter uma qualidade de estro comparÃvel ao natural. Na segunda IA, os tratamentos foram equivalentes nas taxas de prenhez, mas diferiram nas de concepÃÃo (96% âCIDR-Bâ e 76% âOVSYNCHâ). Deste modo, o protocolo âCIDR-Bâ mostrouse mais eficiente na induÃÃo da puberdade em novilhas girolandas com melhores taxas de concepÃÃo e prenhez em primeira IA, reduzindo onsideravelmente a idade ao primeiro parto. AlÃm disso, apresenta-se economicamente viÃvel com possibilidade de reutilizaÃÃo do implante, devendo-se atentar aos cuidados com higiene e manipulaÃÃo do produto. / Two oestrus and ovulation synchronization protocols (CIDR-B and OVSYNCH) were tested on 90 acyclical Girolanda heifers. The animals were distributed in three groups. Group I (n=30) was submitted to the OVSYNCH protocol, consisting of: intramuscular (IM) application of 1.0 ml gonadotropin-releasing hormone (GnRH), 2.0 ml rostaglandin F2a (PGF2a) after 7 days, 1.0ml GnRH 48h later, then timed artificial insemination (TAI) 16h after the second application of GnRH. Group II (n=30) was submitted to the CIDR-B protocol, consisting of: introduction of intravaginal CIDR-B implant and application of 2.0 ml estradiol benzoate (EB) IM, implant removal after 8 days, application of 500 UI pregnant mare serum gonadotropin (PMSG) and 2.0 ml PGF2a, a second IM application of BE 24h subsequently, then TAI 30h later (i.e. 54h following implant removal). Group III (n=30; control group) received no hormonal treatment. Gestation was verified ltrasonographically 35 days after the first, second and third AI. The cost-benefit ratio of each protocol was also determined: The CIDR-B protocol was most efficient in the first AI in which it was comparable to the control group in providing a near-natural oestrus quality (conception and pregnancy rates of 60% and 50%, respectively; p<0.05). In the second AI, the two treatments yielded similar pregnancy rates, but differed in conception rates (96% for CIDR-B; 76% for OVSYNCH). Thus the CIDR-B protocol was the more efficient in inducing puberty in Girolanda heifers, featuring the best conception and pregnancy rates in the first AI and considerably reducing age at first birth. It is moreover economically feasible as the implant may be reused provided apropriate care is given to hygiene and handling.

Foram realizados cinco experimentos com o objetivo de sincronização do estro e indução da ovulação em tempo fixo em éguas. Experimento I: avaliou a eficácia de um novo protocolo hormonal para a sincronização do estro, sendo realizado durante o período transicional em éguas cujo status reprodutivo era desconhecido. Experimento II: foi delineado para determinar o momento ideal para retirada dispositivo intravaginal de progesterona (DIP), sendo o dispositivo retirado no dia 7, 8 ou 9 do protocolo de tratamento hormonal. Experimento III: testou se a eficiência do protocolo é dependente da fase do ciclo estral da égua e definiu o melhor momento para indução da ovulação. Experimentos IV e V: as éguas foram submetidas ao protocolo completo de sincronização da onda folicular e indução da ovulação em diferentes fases do ciclo estral ou com status reprodutivo conhecido. A hipótese testada foi de que a sincronização do estro e indução da ovulação, com o uso do DIP de 1,44g provoca a supressão do crescimento folicular e através da indução da ovulação, com hCG e GnRH, promove a ovulação dentro de 42 ± 6 horas de no mínimo 75% dos animais. Para isso, os efeitos das prostaglandinas e progestágenos foram avaliados quanto à capacidade de sincronizar a onda de crescimento folicular. Um novo tratamento para induzir a ovulação em tempo fixo foi testado com uma combinação de GnRH e hCG em dois momentos estratégicos (D10 e D12) visando maximizar o número de éguas ovuladas. O protocolo com administração de prostaglandina no D0, D6 e D8 juntamente com a colocação do DIP mantido durante 8 dias (D0 ao D7) demonstrou ser eficaz para suprimir a taxa de crescimento folicular em éguas cíclicas. Nas éguas submetidas a este protocolo as ovulações que ocorreram naturalmente se concentraram entre os dias 10 e 13 do tratamento. Foi testada a eficiência da indução da ovulação no D10 e D12. Na maioria dos animais tratados, o folículo pré-ovulatório foi responsivo à combinação de GnRH e hCG promovendo o sucesso da indução da ovulação. A eficiência do protocolo hormonal testado para sincronização do estro e da ovulação foi de 76,73%, sustentando a hipótese deste estudo. Novos estudos devem ser realizados em um maior número de animais para possíveis adequações na terapia hormonal e verificação do resultado em um grande número experimental de animais. / Five experiments were conducted with the objective of estrus synchronization and fixed time ovulation induction in mares. Experiment I: evaluated the efficacy of a new hormonal protocol for estrus synchronization in mares whose reproductive status was unknown during the transitional period. Experiment II: was designed to determine the best time to remove the P4 intravaginal device (PID). The device was removed on day 7, 8 or 9 of the hormonal treatment protocol. Experiment III: tested if protocol efficiency depends on the stage of mares estrus cycle and indicated the best time for hormonal induction of ovulation. Experiments IV and V: mares were submitted to the full protocol of follicular wave synchronization and ovulation induction at different stages of estrus cycle or at known reproductive status. The tested hypothesis was that the estrus synchronization and induction of ovulation, using an PID of 1.44g, causes suppression of follicular growth, and ovulation induction using hCG and GnRH promote ovulation within 42 ± 6 hours of at least 75% of treated animals. The effect of prostaglandin and progestagens at specific times were evaluated for the ability to synchronize follicular wave. A new treatment to induce fixed time ovulation was tested with GnRH and hCG combination in two strategic moments (D10 and D12) to maximize the number of ovulated mares. Administration of prostaglandin at D0, D6 and D8 together with PID maintained for 8 days (D0 to D7) proved to be effective to suppress follicular growth during reproductive period. In mares submitted to this protocol, ovulation occurred naturally and concentrated between D10 and D13. The ovulation induction efficiency was tested at D10 and D12. Most of the animals had preovulatory follicle responsiveness to GnRH and hCG, promoting the success of ovulation induction. The efficiency of the tested synchronization of estrus and ovulation induction protocol was 76.73% and supported the hypothesis of this study. Further studies should be performed on a larger number of animals for possible adjustments in hormonal therapy and verification of the result in a large number of animals.

The biological process of estrus in cattle is known to initiate behavioral responses as a result of fluctuations in hormones, which may alter time budgeted for feeding. The current study aimed to quantify these variations that may exist in feed intake and behaviors in the days pre and post estrus. For this study, 517 estrous cycles in crossbred beef heifers of divergent sizes were used to analyze the impact of estrus behavior on feeding behavior with or without the presence of a bull. There were few differences in estrus behavior among heifers of divergent sizes, however the presence of a bull influenced all estrus activity parameters. Our findings indicate that feed intake and behaviors were sharply decreased on the day of estrus, but returned to baseline levels the following day. Thus, decreases in feed intake and behavior may serve as an additional tool indicating the onset of estrus.

Prolonging function of the corpus luteum (CL) is a method of suppressing estrus that maintains secretion of endogenous progesterone to keep mares out of heat naturally. The use of oxytocin to prolong CL function is becoming more popular. In these therapies, upregulation of cyclooxygenase-2 is inhibited, which impairs prostaglandin F2α ( PGF2α) production. Intramuscular (IM) administration of 60 IU of oxytocin once daily from 7 to 14 days after ovulation is currently the most common treatment protocol. Although that protocol is efficacious in ≥70% of treated mares, the need for daily administration is a drawback to its use. A proprietary slow-release oxytocin formulation (SR-OT) with a two-injection protocol to prolong CL function was evaluated in the first experiment. Mares were examined to determine the day of ovulation (day 0) and then randomly assigned either to a non-treated control group or an SR-OT treatment group (n = 8 mares/group). Mares in the treated group received 1.0 mL of SR-OT containing 2,400 IU oxytocin IM once on Day 7 and again on Day 10 after ovulation. Jugular blood samples were collected on day 0 and then every M, W, and F continuously. Serum progesterone concentrations were evaluated to assess CL function, which was prolonged in 0/8 (0%) control mares and 6/8 (75%) of the SR-OT treated mares (p< 0.01). In a second study, the ability of the endometrium to synthesize PGF2α was evaluated in mares in a state of prolonged CL function. Mares were designated into groups 50-59, 60-69, or 70-79 days post-ovulation (50s, 60s, 70s) and 14-day post-ovulation controls. PGF2α synthesis was evaluated by measurement of a prostaglandin metabolite in response to a single 10 IU intravenous oxytocin bolus (0 minutes). Blood samples were collected serially from 30 minutes before until 120 minutes after oxytocin administration. The metabolite response was significantly higher in the 70s versus the 50s and 70s versus the 60s groups (p< 0.001; p< 0.02, respectively); and there was no significant difference between the 70s group and the control group (P>0.36). Luteal function was maintained after oxytocin administration in 4/4, 3/4, and 0/3 mares in the 50s, 60s, and 70s groups, respectively. Collectively, these results indicate that the luteolytic mechanism returns approximately 70 days into the period of prolonged CL function.

No description available.

Two studies were conducted to determine if 7-d MGA or PRID treatment initiated on d 17 of the estrous cycle altered: 1) follicular development, 2) estradiol-17β (E2) and progesterone (P4) concentrations, and 3) patterns of release of luteinizing hormone (LH). In both studies, Angus, Angus x Holstein or Holstein cows 2 to 6 yr of age were randomly assigned to receive either MGA (.5 mg⋅hd⁻¹⋅d⁻¹; n = 23) or PRID (n = 26) for 7 d or to serve as untreated controls (n = 14). Real time, B-mode ultrasound, equipped with a 7.5 mHz linear-array transrectal transducer, was used to conduct daily ovarian scans beginning 3 (Study 1) or 9 d (Study 2) after onset of estrus. Jugular venous blood samples (45 ml) were collected coincident with ovarian scans. In study 2, cows were fitted with indwelling jugular catheters 17 (Control, MGA and PRID), 20 and 23 d (MGA and PRID) after onset of estrus and blood samples were collected at 15-min intervals for 6 h for determination of LH. Interestrus interval was extended (P<.05) for 3 to 5 d in MGA-treated cows exhibiting two or three dominant follicles (classified as MGA-2 and MGA-3, respectively) or PRID-treated cows compared to controls exhibiting two or three dominant follicles during the estrous cycle (control-2 and control-3, respectively). Forty-four percent of MGA-treated cows ovulated the dominant follicle present at the beginning of MGA treatment. In both studies, days from detection of the ovulatory follicle until ovulation were greater (P<.01) in MGA-2 and control-2 cows than control-3, MGA-3 and PRID cows. Diameter of the ovulatory follicle was greater (P<.01) 9 d before estrus and growth rate of the ovulatory follicle was less (P<.02) in MGA-2 and control- 2 cows than control-3, MGA-3 and PRID cows. Serum P4 decreased 3 d earlier (P<.02) during the estrous cycle of MGA-2 and control-2 cows than control-3, MGA-3 and PRID cows. Serum E2 was greater (P<.01) 7 d before estrus in MGA-2 cows than all other treatment groups. Changes in mean and baseline LH concentrations and amplitude of LH pulses on d 17, 20 and 23 after onset of estrus did not differ (P>.10) among treatments. Luteinizing hormone pulse frequency was greater (P<.03) on d-20 after onset of estrus in MGA-2 cows than MGA-3 and PRID cows (4.3 ± .6 vs 2.6 ± .3 and 3.2 ± .4, respectively). In addition, LH pulse frequency did not differ (P>.10) 17 or 23 d after onset of estrus among treatments. In conclusion, MGA treatment extended the dominance phase of development of ovulatory follicles, which resulted in the premature increase in serum E2 and frequency of LH release, whereas the dominant follicle present at the beginning of PRID treatment underwent atresia and another preovulatory follicle developed. / Ph. D.

Estrus detection programs practiced on most U.S. dairy farms are not intense enough to provide the information needed to accurately time insemination, thus preventing AI from obtaining its full conception rate potential. Herds (n = 17) participated in a trial designed to evaluate percent pregnant relative to various characteristics of estrus. Herds utilized HeatWatch® electronic estrus detection system to detect and record mounting activity for cows in estrus. Inseminations were performed daily during a three hour interval for all cows identified in estrus the previous 24 h. Model characterizing percent pregnant for cows (services = 2661) included effects of interval from first mount to AI (P < 0.01), mounts per estrus (P < 0.01), DIM at insemination (P < 0.01), herd (P <0.05), and season of AI (P < 0.05). As mounts per estrus and days in milk increased, percent diagnosed pregnant increased. Interval affected probability of pregnancy with highest odds ratios for percent pregnant occurring >4 to 16 h following onset of estrus. Model for heifers (n = 306) included linear effects of interval (P < 0.01), season (P < 0.05), and herd (P < 0.01). In dairy heifers, as interval from first mount to AI increased, percent pregnant decreased. Timing of insemination in dairy cows can now be performed relative to first mount of estrus, with highest probability of pregnancy occurring between >4 to 16 h after onset. If onset of estrus is not known, insemination should be performed at the next most convenient time within 3 h. / Master of Science