Blood Factor Fb In Pigs

Anirn. Blood Grps biochem. Genet. I (1970) 125-126

Blood factor Fb in pigs 3. Hradeckjl and 3. Hojnjl Laboratory of Physiology and Genetics of Animals, Libtchov, Czechoslovakia Received: 7 October 1968

Blood group system F in pigs was described by Andresen (1955, 1957) as a one-factor open system. In the course of the Third International Pig Blood Grouping Comparison Test (Gottingen, 1968) some laboratories compared antibodies detecting another blood factor of the F system, designated F b (GB/Sc, SU/CH). The same specificity was found in antibody CZ 18 (CS). Antibody anti-CZ 18 was obtained from sow L 49-25 (Landrace breed) by immunization with blood from a closely related boar L 314/5. Owing to its low titre, the monospecific serum was tested in the dextran test (Hojnjl and Hradecky, 1968). We tested 552 pigs of the Large White, Landrace, Black and White, PieStice and Cornwall breeds and a group of laboratory pigs, and did not find a single animal to react negatively with both CZ 18 and antibody anti-Fa (the same as Voron, 1968, pers. comm.). These findings caused us to devote more attention to the relationship between these factors by observing families from selected types of mating. The results of the distribution of 218 offsprings from 27 families according to F phenotypes (Table 1) showed that blood factor Fa and anti-CZ 18 (Fb) are opposite markers of one genetically closed system. The three genotypes correspond to the three known phenotypes: Phenotype F(a+b-) F(a+ b F(a-b+)

+>

Genotype

FaFa FaFb FbFb

The results of parallel testing of 234 animals proved the full identity of our reagent Fb (CZ 18) with antibody Fb (SU/CH) of the Kharkov laboratory. Unsolved, however, remains the question of identity of the above reagents with anti-Fb of the Edinburgh laboratory (GB/SC). According to a personal communication with Dr Imlah (1968) and contrary to our results, there are animals that are negative with both antibody Fa and Fb. If his results are not due to antibodies of different specifity, it may be presumed that the theory of a closed F-system need not apply to all pig breeds. This would be similar to the case of blood factors Ha and Hc (Andresen, 1964). In agreement with the results of Fa allele frequency (Gavalier et al., 1966), the new blood factor F b occurs at a high frequency in all breeds tested.

126

J. HRADECKP AND J. HOJN?

TABLE 1. Distribution of offsprings from 27 families of selected types of mating according to F phenotypes. Type of mating Number of families

Number of offsprings

z2

Distribution of offspring according to phenotypes Fa

FaFb

Fb

obexobexobexserved pected served pected served pected Fa x Fa Fa x FaFb Fa x Fb FaFb x FaFb FaFb x Fb FbXFb

2 3 4 3 12 3

12 18 36 15 106 31

12 12

4

-

12 9

3.75 -

-

-

-

-

6 36 8 54 -

9 36 7.5 53 -

-

-

-

-

2.00

3 52 31

3.75 53 31

0.17 0.04

References Andresen, E., 1955. Blood groups of the pig. Danish.) Ugeskr. Landm. 100: 555-561. Andresen, E., 1957. Investigations on blood groups of the pig. Nord. VetMed. 9: 274-284. Andresen, E., 1964. Further studies on the H blood group system in pigs with special reference to a new red cell antigen Hcl. Acta genet. Base1 14: 319-326. Gavalier, M., Hojnjr, J., Hradeckjr, J., Linhart, J. & Schroffel, J., 1966. Blood groups and serum proteins in pigs. Polymorphismes biochimiques des animaux Xe Congr. eur. Grpes sang. Polymorph. biochim. Anim., Paris, p. 159-164. Hojnjr, J. & Hradeckjr, J., 1968. Dextran-test in the study of blood groups in pigs. XIth Conf: Blood Grps Protein Polymorphism Anim. Warsaw, 1-6 July 1968.

Anim. Blood Grps biochem. Genet. 1 (1970)