The use of synthetic progestagens released by vaginal devices is an important tool to overcome the Palavras-chave: pessário intra-vaginal, CIDR ® , esponja, progestageno, vaginite, ovelha.

No abstract

The aim of this study was to evaluate swine females of different genetic lines submitted to different reproductive management and housing systems during pregnancy on reproductive performance and animal welfare parameters. After artificial insemination protocol, 524 females were divided into two gestation housing systems: PEN1=animals housed in individual stalls during the breeding and after group-housed; PEN32=animals housed in individual stalls from breeding until 32 days of pregnancy and after group-housed. The number of piglets born, and the pregnancy and farrowing rates were evaluated. Welfare parameters related to the pregnancy phase were used. Females who weaned more piglets in the previous farrowing had a higher number of piglets born at the next farrowing. The pregnancy rate was affected by the number of semen doses. The farrowing rate was not influenced by the evaluated parameters, with average value of 91.36%. There was no effect of the gestation housing system and the genetic lines on pregnancy and farrowing rates, with values above 90.0%. The animal welfare indicators showed more compromised parameters in PEN1 system. PEN1 system did not impair the reproductive performance although it presented more compromised animal welfare parameters.

0,05). Na avaliação efetuada no D9, não foram constatadas diferenças (P>0,05) no percentual de blastocistos eclodidos, entre os dois sistemas de cultivo (29% e 24% para CP e TcP, respectivamente). Após coloração fluorescente dos núcleos, não foi observada diferença (P>0,05) entre o número médio de células dos blastocistos eclodidos (182,66 vs. 202,8) e expandidos (94,5 vs. 88), para o CP e TcP, respectivamente. Blastocistos bovinos produzidos in vitro podem ser cultivados individualmente do D7 ao D9, não havendo efeito do sistema de cultivo empregado (placas ou palhetas) sobre a taxa de eclosão e o número de células.]]>

The synthetic progestin altrenogest (ALT) has been widely used in sow farms to concentrate artificial inseminations (AIs) during the transition of weekly productive flow for the batch farrowing system of 14 or 21 days. The objective of the present study was to investigate the effect of the duration of ALT treatment on the reproductive performance of weaned sows during transition to batch farrowing. Retrospective data was evaluated regarding the reproductive performance of primiparous and multiparous sows that were either not treated (control, n = 165) or treated with 20 mg ALT during 7 days (ALT7, n = 161) or 14 days (ALT14, n = 199) post-weaning. The interval between weaning or the end of ALT supplementation and first AI did not differ among the groups, as well as the percentage of sows inseminated up to 7 or 10 days after the end of treatment or weaning (P ≥ 0.16). There was a tendency for a lower farrowing rate (P = 0.06) in ALT7 (77.2%) when compared to ALT14 (84.5%) and control (86.3%) groups. The total number of piglets born did not differ among groups (P = 0.35). In conclusion, despite the slight delay in the estrus onset, the proportion of estrous sows was not affected, whereas the adjusted farrowing rate was reduced when ALT was administered for 7 days after weaning in multiparous sows during transition to 21 days batch farrowing system.

In vitro embryo production (IVP) is an attractive technique because of the low-cost production of numerous bovine embryos, use in somatic cell and embryo cloning, production of transgenic cows, as well as for basic research. Protein in the culture media appeared to be one of the most significant limiting factors in the different steps of this technology. These protein sources are represented mostly by biological materials which provide nutrients and other poorly understood factors for the embryos. This study evaluated the possibility of using mare´s serum obtained at different stages during oestrus for bovine in vitro production. Complexes cumulus-oocytes (CCO) from slaughtered cows ovaries were matured in a controlled incubator (39ºC, 5%CO 2 , saturated humidity) for 22-24h in TCM-199 + HEPES + bLH + hFSHr + 10% mare serum collected at the 1 st day of oestrus (T1), 24-48h before ovulation (T2) and 24-48h after ovulation (T3) and a control group (C), using the same medium added 10% oestrus cow serum. In vitro fertilization (IVF) was performed in TALP-FERT under the same conditions and in vitro culture (IVC) on synthetic oviduct fluid (SOF)+5% of T1, T2, T3 or C serum, during 8 days under mineral oil. Cleavage rates were similar between treatments. Blastocyst rates at D7 were higher (T1=21%, T2=21% and T3=20%; P <0.05) than the controls (12%). Hatching rates in T1 (9,8%-47/477) were higher (P<0.05) than T2 (3.1%-15/477), T3 (4.2%-21/505) and C (4.1%-20/486). Hatched blastocysts of T3 had a lower (P<0.05) number of cells than those of T1 and Control. Considering it´s heterologous nature, the possibility of preventing disease transmission and the higher blastocyst rates at D7 reported here, the use of oestrus mare´s serum can be used for the IVP of bovine embryos.

0,05) entre os grupos. O fluido folicular de folículos médios e grandes pode ser utilizado para o manutenção de oócitos bovinos por 6h a 30°C, antes da maturação por 18h.]]>

Temperature and rainfall were analyzed daily during six years to evaluate their influence on in vitro production of bovine embryos. Weekly replications (n=480) were performed on 14,778 ovaries collected at slaughterhouses. Cumulus oocyte complexes (n=19,180) were fertilized with a pool of Bos taurus taurus semen in one incubator with 5% CO 2. Presumable zygotes were cultured in gasified plastic bags with 5% CO 2 , 5% O 2 , and 90% N 2 . In the first year, cleavage and embryo yield were 60.3% and 15.6%, respectively, being lower (P<0.05) than in the following years. Average cleavage rates were always lower in winter (P<0.0001), thus producing less embryos. Winter climatic conditions had a negative influence on in vitro production, when cleavage and embryo yield declined, possibly because of reduced availability and growth of native pasture.