| First Author | Krzanowska H | Year | 1965 |
| Journal | Mouse News Lett | Volume | 32 |
| Pages | 54-56 | Mgi Jnum | J:2444 |
| Mgi Id | MGI:50967 | Citation | Krzanowska H (1965) New inbred strains. Mouse News Lett 32:54-56 |
| abstractText | Full text of MNL contribution: New inbred strains of mice bred in the Department of Animal Genetics, Jagiellonian University, Cracow, Poland. Origin: Started in 1952 from F1 generation obtained by crossing two individuals: coAaBBPP (albino) x CCaabbpp (pink-eyed dilution, chocolate) of unknown origin. Twenty inbred strains of different genetic markers and an outbred strain were started and designated with the successive letters of the alphabet. Only two inbred strains, named KE and KP, survived, and have been successfully bred till now (38th generation of sister-brother mating). Characteristics: The characters of both inbred strains and their reciprocal crosses are presented in the accompanying table. Both strains perform very well at crossing. Heterosis refers especially to their reproductive performance. When compared with F1 crosses, inbred strains show a high degree of inbreeding depression, in each strain different stages of fertility being affected. Strain KE: normal ovulation rate, poor fertilization, low embryonal and postembryonal mortality (rather good maternal environment). Poor fertilization rate is connected with a high incidence of abnormal spermatozoa. The process of fertilization is retarded about 2 hrs when E strain sperm is used. Strain KP: lowered ovulation rate, fairly good fertilization rate in fertile matings but a high incidence of sterile copulations, high embryonal and postembryonal mortality (poor maternal environment) low libido of males. Further research aimed at elucidating hormonal aspects of the lowered fertility in both strains is still in progress. Also the inheritance of the factor(s) responsible for the high incidence of sperm abnormality is being investigated in the F2's and the back-crosses. Table: Character: phenotype; Strain KE: albino; Strain KP: chocolate pink-eyed dilution; F1: chocolate; Reference: -. Character: genotype; Strain KE: ccaabbPP; Strain KP: Ccaabbpp; F1: CcaabbPp; Reference: -. Character: mean body weight: a) at weaning (3 w.): Strain KE: 8.4 g; Strain KP: 7.5 g; F1: 8.5 g; Reference: Krzanowska 1963; b) 10 weeks, female: Strain KE: 22.3 g; Strain KP: 20.0 g; F1: 23.6 g; Reference: Krzanowska 1963; c) 10 weeks, male: Strain KE: 24.1 g; Strain KP: 23.6 g; F1: 26.4 g; Reference: Krzanowska 1963; d) 10 months, male: Strain KE: 35.2 g; Strain KP: 29.1 g; F1: 39.8 g; Reference: Krzanowska 1962; Character: mean length of oestrous cycle (days): a) in the absence of a male; Strain KE: 6.2; Strain KP: 4.8; F1: 4.7; Reference: Krzanowska in press; b) with a male present; Strain KE: 4.9; Strain KP: 4.1; F1: -; Reference: -; Character: mean number of ovulated ova; Strain KE: 11.4; Strain KP: 10.1; F1: 12.0; Reference: Krzanowska 1961; Character: percentage of fertilized ova, 24 hrs after coitus X); Strain KE: 74%; Strain KP: 86%; F1: 100%; Reference: Krzanowska 1960; Character: percentage of eggs with second polar body extruded X) 4 hrs after coitus; Strain KE: 33%; Strain KP: 46%; F1: 97%; Reference: Krzanowska 1964; Character: mean litter size X); Strain KE: 6.1; Strain KP: 5.0; F1: 11.2; Reference: Krzanowska 1963; Character: mean testes weight of adult males; Strain KE: 197 mg; Strain KP: 229 mg; F1: 238 mg; Reference: Krzanowska 1962; Character: mean number of spermatozoa in ejaculate (millions); Strain KE: 5.13; Strain KP: 4.38; F1: 9.89; Reference: Krzanowska 1962; Character: percentage of spermatozoa with abnormal heads; Strain KE: 17.6%; Strain KP: 7.7%; F1: 3.7%; Reference: Krzanowska 1962; X) data refer to sister-brother mating, both in inbred, strains and in F1 generation. References: Krzanowska H. 1960. Studies on heterosis. II. Fertilization rate in inbred lines of mice and their crosses. Folia Biologica. 8: 269-279. Krzanowska H. 1961. Analysis of the higher fertility in crossbred animals (in Polish). Roczn, Nauk Roln. 78-B-1. 97-114. Krzanowska H. 1962. Sperm quantity and quality in inbred lines of mice and their crosses. Acta Biologica Cracoviensia. Ser. Zool. 5: 279-290. Krzanowska H. 1963. Fl crosses as a laboratory material (in Polish). Zwierzeta Laboratoryjne. 1. 36-43. Krzanowska H. 1964. Time interval between copulation and fertilization in inbred lines of mice and their crosses. Folia Biologica 12: 231-244. Krzanowska H. 1964. Studies on heterosis. III. The course of the sexual cycle and the establishment of pregnancy in mice, as affected by the type of mating. Folia Biologioa (in press). |
