Rafael Kummer

Reproductive Performance of Gilts with Similar Age but with Different Growth Rate at the Onset of Puberty Stimulation

The aim of this study was to evaluate the reproductive performance of gilts that had a similar age but different weights at the onset of puberty stimulation by boar exposure at 144 days. Gilts were divided into two groups according to their lifetime growth rate from birth to approximately 144 days of age. Mean growth rates at this moment were 577 and 724 g/day for group 1 (G1; n = 58) and group 2 (G2; n = 58), respectively. After selection, gilts were weighed at approximately 155, 165 and 175 days of age, on the insemination day and at slaughter. Gilts were inseminated, on average, at 193 days of age and were slaughtered 32 days after insemination, when the number of corpora lutea and embryos were recorded. Higher growth rate gilts (G2) reached puberty earlier (155.3 vs 164.1 days; p < 0.01). More gilts of G2 group attained puberty by 190 days of age (p = 0.004) than G1 gilts (95%; 55/58 vs 76%; 44/58). The anoestrous rate, until 60 days after the onset of boar exposure was higher (p < 0.01) in G1 (19.0%; 11/58) than in G2 (3.4%; 2/58) group. However, there were no differences in the pregnancy rate (90.7 vs 94.5), ovulation rate (15.9 vs 16.5), total embryos (12.9 vs 11.7), viable embryos (12.0 vs 11.1) and embryo survival (73.7% vs 68.5%), between G1 gilts and G2 gilts, respectively (p > 0.05). High growth rate gilts attain puberty earlier and have a lower anoestrous rate than low growth rate gilts.

Nova pipeta para inseminação intra-uterina em suínos

The aim of this work was to evaluate the reproductive performance of 423 sows of 1 to 9 farrowings inseminated with two different intrauterine artificial insemination (IAU) pipettes. The first group (T1) was formed by sows inseminated with a new pipette whose extremity was not fixed in the cervix. The second group (T2) was formed by sows inseminated with a Verona® pipette model, with its extremity fixed in the cervix. The degree of difficulty to perform the insemination, the time spent during the insemination, the presence of blood after insemination and of semen backflow during insemination were considered for the comparison of these pipettes. Return to oestrus rate (RO), pregnancy rate (PR), adjusted farrowing rate (AFR) and total litter size (TLS) were also evaluated. All females were inseminated with 1 billion spermatozoa per dose applied at intervals of 24 hours. The catheter of IAU was successfully inserted in 95.9% of females without difference between treatments (P>0.05). The presence of blood, in at least one insemination, was observed in 20.6% of T1 and 15.2% of T2 females (P=0.14). The average time to perform the insemination was 2.1 minutes for T1 and 2.3 minutes for T2 females (P=0.26). The percentage of females with semen backflow was significantly higher (P=0.01) in T1 (8.4%) compared to T2 (2.9%) group. There were no differences (P>0.05) in RO (8.0% and 4.8%), PR (93.4% and 96.2%) and TLS (12.4 and 12.7 piglets) between T1 and T2 groups, respectively. AFR of T1 (90.6%) tended (P=0.07) to be lower than that of T2 (95.1%). Primiparous females of T1 showed higher RO and lower AFR in comparison to pluriparous (P<0.05). The results indicate that the new pipette can be used

Comparação entre diferentes métodos de inseminação artificial em suínos

O objetivo deste trabalho foi avaliar tres metodos de inseminacao artificial(IA) no suino em relacao ao tempo de infusao e perdas por refluxo da DI durante a IA e aos 120 minutos apos a IA, bem como dados de operacionalidade medido pelo grau de dificuldade verificado para execucao da IA e dados de desempenho reprodutivo. Foram utilizadas 604 matrizes ate a paricao 7 e IDE 0,05). As taxas de retorno ao estro foram 10,3, 7,4 e 8,5 %, a taxa de parto ajustada foi de 90,8, 94,0 e 91,7% com 10,9, 11,1 e 11,1 leitoes nascidos totais em T1, T2 e T3, respectivamente. O metodo auto IA e o metodo intermediario proporcionam IAs mais rapidas e podem substituir o metodo tradicional sem prejuizos ao desempenho reprodutivo.

Two different feeding levels during late gestation in gilts and sows under commercial conditions: impact on piglet birth weight and female reproductive performance

The increase in the litter size in past decades has caused reduction in the individual piglet birth weight. Therefore, nutritional strategies employed in the last third of gestation in order to improve the piglet birth weight have been studied. This study aimed to evaluate the effects of 2 different feeding levels (1.8 and 2.2 kg/d) in the last third of gestation on the piglet birth weight and the female reproductive performance. A total of 407 females were fed on a diet based on corn-soybean meal (3.25 Mcal ME per kg and 0.65% standardized ileal digestible lysine) from day 90 of gestation until farrowing. The females were weighed on day 90 and day 112 of gestation, and at weaning. Born alive and stillborn piglets were weighed within 12 h of birth. The lactation feed intake and the litter growth rate were measured in a randomly selected subsample of 53 sows from each treatment. The data were analyzed using the generalized linear mixed models, considering the females as the experimental unit. Parity, treatment, and their interaction were analyzed for all responses. The females fed on 2.2 kg/d of diet from day 90 to day 112 exhibited greater body weight gain compared to the females fed on 1.8 kg/d (P < 0.001). No evidence of the effects of feeding levels on the individual piglet birth weight and on the within-litter CV were observed, for both gilts and sows (P ≥ 0.90). Similarly, when the classes of the total born piglets were considered in the analysis (<15 and ≥15 for gilts; <16 and ≥16 for sows), no positive effects of increasing the feeding level were observed on the individual piglet birth weight and the within-litter CV (P ≥ 0.47). Also, no differences in the stillborn rate, mummified-fetus rate, and percentage of piglets weighing less than 1,000 g at birth were observed between the treatments (P ≥ 0.28). The females fed on 1.8 kg/d of diet exhibited greater feed intake during lactation, compared to the females fed on 2.2 kg/d (P < 0.05). Weaning weight, weaning-to-estrus interval, subsequent litter size, and culling rate were not affected by the dietary levels (P ≥ 0.23). In conclusion, increasing the feed intake from day 90 of gestation until farrowing increased the body weight gain in sow, demonstrated no effect on the piglet birth weight, and reduced the lactation feed intake. Furthermore, there was no evidence of the effects of the treatments on the litter growth rate or on the subsequent female reproductive performance.