The effect of environmental and genetic effects on the farrowing interval in Dalland (C-40) sows in the Southeast of Brazil was studied. Data consisting of 1,013 farrowing intervals recorded in two herds were analyzed, using a model that included the sire and the dam as random effects and the year of farrowing, the herd and the farrowing season as fixed effects, plus the covariables sow's age at farrowing, litter size at birth, lactation length and weaning-estrus interval. For the farrowing interval first only, variance components were estimated by REML, with an animal model that included, as fixed effect, a contemporary group and, as random effects, the additive genetic variance and the error. The mean farrowing interval was 140.9+5.7 days, with a 4.0% coefficient of variation. Variance analysis showed no effect of either year, season of farrowing or herd on the farrowing interval. The sire effect was not important for the farrowing interval, but the dam represented an important source of variation. The total number of piglets born and the sow's age at farrowing had no influence on the farrowing interval. The length of lactation exerted an influence on the farrowing interval, accounting for 19.4% of the total variation of this trait. Likewise, the linear regression of the weaning-estrus interval in relation to the farrowing interval was highly significant, accounting for 51.7% of the total variation. The heritability estimate was 0.00, suggesting that no genetic gain can be obtained by selection for a shorter farrowing interval.

The genetic and environmental factors that affect age at first conception (AFC) of gilts were evaluated, using 466 observations of Dalland animals (C-40). The software program MTDFREML was used to assess the genetic parameters on an animal model that included as fixed effect, contemporary group and, as random effects, the additive genetic, the common litter and the error. Mean value of AFC was 241.12±25.9 days, with CV of 8.5 %. Variance analysis showed that year (P<0.01), season (P<0.01) and herd effects (P<0.01) were important sources of variation of AFC. The throat effect (P=0.34) was not important for the AFC, but the mother of the gilts (P<0.01) was an important source of variation. The heritability estimate was 0.44±0.14 that this trait would yield genetic gain as a response to the selection.

Avaliaram-se o desempenho, as características de carcaça e a viabilidade econômica de coelhos sexados abatidos em diferentes idades. Foram usados 100 coelhos (50 machos e 50 fêmeas), em delineamento de blocos inteiramente ao acaso e arranjo fatorial 2×2 (dois sexos e duas idades ao abate), com quatro tratamentos e cinco repetições. Os coelhos foram desmamados aos 35 e abatidos aos 75 ou 90 dias de idade. Não houve diferença entre sexo (P>0,05) nos parâmetros avaliados. Os animais abatidos aos 90 dias (P<0,001) eram mais pesados e consumiram (diário) mais ração. Os abatidos aos 75 dias (P<0,001) ganharam mais peso (diário) e apresentaram melhor conversão alimentar. Coelhos abatidos aos 90 dias de idade tiveram maiores pesos relativos de carcaça (P<0,04), de coxa (P<0,001), de gordura interna (P<0,001) e de fígado (P<0,01) e, ainda, apresentaram maior peso final e melhores características de carcaça, cuja venda foi mais lucrativa quando realizada aos 75 dias ou quando foram abatidos aos 90 dias de idade.

Performance, carcass characteristics and economic viability of sexed rabbits slaughtered at different ages were evaluated. One-hundred rabbits (50 males and 50 females) were assigned to a completely randomized block design in a factorial arrangement of 2×2 (two sexes and two slaughter ages), with four treatments and five replicates. The rabbits weaned at 35 were slaughtered at 75 and 90 days of age. No effect of sex (P>0.05) on the evaluated parameters was observed. Animals slaughtered at 90 days were heavier(P<0.001), had a higher daily feed intake and a higher carcass weight than animals slaughtered at 75 days which showed higher daily weight gain and better feed: gain ratio. Rabbits slaughtered at 90 days of age had higher carcass weight (P<0.04), thigh (P<0.005), internal fat (P<0.001) and liver (P<0.01). They also showed better carcass characteristics. High rentability was obtained alternatively for animals sold alive at 25 days of age or slaughtered at 90 days of age.

RESUMO O trabalho teve por objetivo estudar, por meio da técnica de soroaglutinação microscópica, a ocorrência de anticorpos para leptospira em populações de javalis, de diferentes cariótipos (2n=36, 2n=37 e 2n=38), criados em sistema semiconfinado. Foram analisadas 203 amostras de plasma sangüíneo de javalis (46 machos, 156 fêmeas e 1 intersexo) de seis municípios do Estado de São Paulo e dois do Estado do Paraná. Dessas amostras examinadas, 132 apresentaram cariótipo 2n=36, 44, 2n=37, 17, 2n=38 e 10 não foram cariotipadas, sendo uma delas de animal intersexo. Do total de animais, 43 (21,2%) foram reagentes e 160 (78,8%) não reagentes. Das 43 amostras reagentes, 25 reagiram contra o sorovar patoc, 13 contra o sorovar icterohaemorrhagiae e 5 contra o sorovar hardjo. Com relação ao sexo, 10 (21,7%) dos javalis machos e 32 (20,5%) das javalis fêmeas foram reagentes; o intersexo foi reagente. A relação entre reagentes e cariótipos mostrou que, dos 132 javalis com cariótipo 2n=36, 19 (14,4%) foram reagentes, nove (6,8%) reagiram contra o sorovar patoc, sete (5,3%) contra o icterohaemorrhagiae e três (2,3%) contra o sorovar hardjo. Dos 44 animais examinados com cariótipo 2n=37, 14 (31,8%) foram reagentes, sendo nove (20,4%) contra o sorovar patoc, quatro (9,1%) contra o icterohaemorrhagiae e um (2,3%) contra o sorovar hardjo. Das 17 amostras examinadas de javalis com cariótipo 2n=38, seis (35,3%) foram reagentes, sendo que cinco (29,4%) apresentaram anticorpos para o sorovar patoc e uma (5,9%) para o sorovar icterohaemorrhagiae. Já das 10 amostras não cariotipadas, quatro (40%) foram reagentes, sendo que duas (20%) reagiram para o sorovar patoc, uma (10%) para o sorovar icterohaemorrhagiae e uma (10%) para o sorovar hardjo. Os dados do presente trabalho não permitem associar os grupos genéticos com a susceptibilidade à infecção por leptospira, uma vez que as proporções de reagentes observadas podem estar associadas às diferenças de condições sanitárias entre os rebanhos estudados. estudar microscópica 2n36 n 2n 36 (2n=36 2n37 37 2n=3 2n38 , 38 2n=38) semiconfinado 20 46 (4 15 Paraná 2n=36 cariotipadas 4 21,2% 212 21 2 (21,2% 16 78,8% 788 78 8 (78,8% hardjo sexo 21,7% 217 7 (21,7% 3 20,5% 205 (20,5% reagente 14,4% 144 (14,4% 6,8% 68 6 (6,8% 5,3% 53 (5,3% 2,3% 23 (2,3% 31,8% 318 31 (31,8% 20,4% 204 (20,4% 9,1% 91 9 (9,1% 35,3% 353 35 (35,3% 29,4% 294 29 (29,4% 5,9% 59 (5,9% 40% 40 (40% 20% (20% 10% (10% estudados 2n3 (2n=3 2n= ( 21,2 (21,2 78,8 (78,8 21,7 (21,7 20,5 (20,5 14,4 (14,4 6,8 (6,8 5,3 (5,3 2,3 (2,3 31,8 (31,8 20,4 (20,4 9,1 (9,1 35,3 (35,3 29,4 (29,4 5,9 (5,9 (40 (20 (10 (2n= 21, (21, 78, (78, 20, (20, 14, (14, 6, (6, 5, (5, 2, (2, 31, (31, 9, (9, 35, (35, 29, (29, (2 (1 (2n (21 (78 (14 (6 (5 (31 (9 (35 (29 (7 (3

ABSTRACT This research aimed to investigate, by the microscopic agglutination test, the occurrence of antibodies to leptospira in wild boar populations, with different karyotypes (2n=36, 2n=37 and 2n=38), raised in semiconfined system. Two hundred and three blood plasma samples from wild boars (46 males, 156 females and 1 intersex) from 6 municipalities of the State of São Paulo and 2 from the State of Paraná were analysed. From these samples, 132 had karyotype 2n=36, 44 had karyotype 2n=37, 17 had karyotype 2n=38 and 10 were not karyotyped (one of them was an intersex). From the animals studied, 43 (21.2%) were reactors, 25 reacted to the serovar patoc, 13 to the serovar icterohaemorrhagiae and 5 to the serovar hardjo. With regard to the sex, 10 (21.7%) of the males and 32 (20.5%) of the females were reactors; the intersex was a reactor. The relationship between serological reaction and karyotype showed that from the 132 wild boars with karyotype 2n=36, 19 (14.4%) were reactors; from the 44 animals with karyotype 2n=37, 14 (31.8%) were reactors; from the 17 samples of wild boars with karyotype 2n=38, 6 (35.3%) were reactors, and from the 10 non-karyotyped samples, 4 (40.0%). The results of this study did not allow to associate genetic groups with susceptibility to leptospira infection, since the reactor rates observed may be related to the differences in sanitary contitions among the herds. investigate test populations 2n36 n 2n 36 (2n=36 2n37 37 2n=3 2n38 , 38 2n=38) system 46 (4 15 analysed 2n=36 one intersex. . studied 21.2% 212 21 (21.2% reactors patoc hardjo sex 21.7% 217 7 (21.7% 3 20.5% 205 20 (20.5% 14.4% 144 (14.4% 31.8% 318 31 8 (31.8% 35.3% 353 35 (35.3% nonkaryotyped non 40.0%. 400 40.0% 40 0 (40.0%) infection herds 2n3 (2n=3 2n= ( 21.2 (21.2 21.7 (21.7 20.5 (20.5 14.4 (14.4 31.8 (31.8 35.3 (35.3 40.0 (40.0% (2n= 21. (21. 20. (20. 14. (14. 31. (31. 35. (35. 40. (40.0 (2n (21 (20 (14 (31 (35 (40. (2 (1 (3 (40