Genetic Markers of Resistance to Leptospirosis in Pigs of the Large White

Przy tu lsk i T., D. Porae czkowska: Genetic Markers of Resistance to Leptospirosis in Pigs of the Large White Polish Breed. Acta vet. Brno, 49, 1980: 237 -244. , Data obtained from 1200 Large White pigs in two farms show that in pigs producing Am BB, Akp AB, Pra AB or BB, Tf AB there is a significantly lower incidence of leptospirosis than in pigs producing Am AB, Akp BB or Be, Pra AA and Tf BB phenotypes. A significantly lower incidence also appears in pigs heterozygous for Hpx as compared to homozygous and a higher incidence in homozygotes Hpx 1-1 as compared to the other homozygous considered together. This result was confirmed by the relationship between these phenotypes and the level of leptospira antibodies as" well as by the effect of selection in relation to polymorphic loci. Leptospirosis, pigs, polymorphism, resistance, blood. Leptospirosis in an important zoonotic disease. A large percentage of cases in domestic animals and wildlife animals was described by Zamora et a1. (1975), Smith er a1. (1976), Bizo n (1973), Sebek et a1. (1976), Sebek and Ro sicky (1975), Mateew and Manew (1975), Shotts et a1. (1975) Livestock herds can be protected against leptospirosis by a combination of proper management and vaccination procedures. The other way to protect the herds against leptospirosis is by breeding resistant animals. Pl esko (1977) found that young Chinese hamsters (Cricetulus griseus) were susceptible to the infection with leptospirosis. However, the animals inoculated with the cultures of the strains of Ballum and Tarassovi serogrups recovered and appeared healthy. The genetic resistance to leptospirosis in pigs of Large White breed has been described by Przytulski and Porzeczkowska (1980). The percentage of progeny with positive results from matings between resistant boars and sows was very small (2.2 %).On the other hand the percentage of progeny with positive results from matings between susceptible boars and sows was the highest (67.1 %). The phenotypes of blood enzymes and proteins may be genetic markers of resistance or susceptibility to leptospirosis in animals. Only a few studies are available on the association of protein and enzyme polymorphism in blood with leptospirosis in animals. Hodges et a1. (1976) analyzed relationship of haemoglobin phenotypes with leptospirosis in sheep and they found that sheep with AB type haemoglobin exhibited more marked following inoculation with L. pomona, than those with haemoglobin types A or B. The relationships between phenotypes of enzyme and protein in blood serum and leptospirosis in pigs was described by Przytulski and Porzeczkowska (1976, 1979b, 1979c). The aim of our investigation was to find differences in serological diagnosis of leptospirosis according to the phenotypes for blood serum protein and enzyme as well as the relationship between polymorphic systems and the level of leptospira antibodies.