Detection of universal variable fragments as markers for genetic studies. A novel technology for DNA fingerprinting.

A novel DNA technology enables the detection of universal variable fragments (UVF), thus revealing genetic variation without a priori sequence information. The detection of UVF markers is based on two amplifications of genomic DNA with the polymerase chain reaction. In the first amplification, two short oligonucleotide primers produce a large number of fragments. One primer is based on a microsatellite sequence, whereas the second primer can have any sequence. In the second amplification, the length of the primers is increased in order to decrease the number of amplicons. This enables the selection of polymorphic fragments. Restriction digestion can be used to further increase the number of polymorphisms. Until now, we have demonstrated UVF in several different species. In addition, with the present study we have contributed to the linkage map of the rabbit by localizing 11 UVF markers on different linkage groups. Mendelian inheritance was shown in this linkage study through a backcross of two inbred rabbit strains. The power of the UVF technique is based on the selection for microsatellite variation in combination with the detection of single-nucleotide polymorphisms. UVF thus offers the possibility of increasing the clustering of markers and localizing genes in species for which sequence information is either not present or only scarcely present.

A carcinogenicity study with mutagenic organic concentrates of drinking-water in the Netherlands.

The carcinogenicity in male and female Wistar SSP TOX rats of organic drinking-water concentrates that are positive in the Ames test was studied at three doses. The organic mutagenic concentrates were prepared weekly from drinking-water from one location in The Netherlands by adsorption onto XAD-4/8 resins and elution with dimethylsulphoxide. The organic concentrates in dimethylsulphoxide were mixed with non-mutagenic drinking-water before exposure of the rats. Dose levels were based on multiples of expected human exposure levels. For the calculation the average human daily intake of drinking-water was taken as 2 litres for a body weight of 70 kg. There was no significant increase in tumour induction when male Wistar SSP TOX rats were exposed for 106 wk to 4.5, 14 or 40 times the expected human exposure level and females to 7,22 or 68 times the human level. The development and types of tumours were similar in the treated and control groups. The numbers of animals with tumours and of animals that died as a result of tumours in the exposed groups did not differ significantly from those in the control groups. These results suggest that these organic mutagenic drinking-water concentrates did not contain very potent carcinogens in effective concentrations.

[Neonatal hemolytic icterus in foals. A study of antibodies in colostrum and serum]. / Neonatale hemolytische icterus bij het veulen. Een onderzoek naar antilichamen in colostrum en serum.

Investigations for the presence of antibodies to red blood cell antigens were carried out in equine colostrum and serum. Material from 181 mares without clinical disease was tested. The object was to obtain information on the number of mares producing antibodies capable of inducing haemolytic disease in newborn foals. Of the mares 2.8% was positive for haemolysins. These mares are expected to be a risk for haemolytic disease. In addition agglutinating antibodies were identified in 39.2 per cent of the mares examined. It is not known whether or not these antibodies constitute a hazard for the foals. A smaller group of sera from mares was analysed to verify or disprove the diagnosis of haemolytic disease. Some of these mares showed very high haemolysin titres. Several cases are reported in greater detail. It is clear that the information obtained from these cases shows that haemolytic disease of newborn foals also occurs after the first pregnancy of mares.

[Twins in cattle. Freemartin or not a freemartin? Preliminary Communication]. / Tweelingen bij runderen. Wel of geen kwee? Voorlopige mededeling.

The preliminary results of comparative studies designed to make it possible to establish a diagnosis of 'freemartin' are reported. Three methods were used, namely typing of the blood, chromosome analysis and determination of the length of the vagina. In a very large number of cases, the diagnosis may even be established in very young calves by measuring the length of the vagina. Laboratory studies may provide a solution in doubtful cases.

[American Quarter Horses and HYPP]. / American Quarter Horses en HYPP.

Hyperkalaemic periodic paralysis is a genetic disease that affects the American Quarter Horse population and is caused by a mutation. As a result of this mutation in a gene which codes for the sodium channel in muscle cells, severe muscle weakness can appear. Reliable DNA-tests can establish whether a horse is homozygous negative, heterozygous, or homozygous positive for this mutation. Therapy and prevention are discussed.

[Twins in cattle. Freemartin or not? Current aspects]. / Tweelingen bij runderen. Wel of geen kwee? Actuele informatie.

Methods are described for the detection of freemartins. The first step is to measure the length of the vagina, followed, if necessary, by laboratory investigations--blood group, chromosome, or DNA typing.

[The relationship between hereditary characteristics in the blood (Phi-PO2-Pgd) and susceptibility to stress in swine. A pilot study]. / De relatie tussen erfelijke kenmerken in het bloed (Phi-PO2-Pgd) en stressgevoeligheid bij varkens. Een oriënterend onderzoek.

Deaths during transport and the incidence of a poor quality of the meat in pigs were the most important reasons for studying the stress-syndrome (MHS) during the past twenty years. MHS is controlled by an autosomal Hal locus with two alleles N and n. Only pigs of genotype nn are sensitive to halothane and susceptible to stress. As a standard test for use in practice, the halothane test was developed in the Netherlands in 1974 and only this test is used to detect MHS. Heterozygotes can not be detected using this test. Since 1986, additional blood typing was carried out for the systems Phi, Po2 en Pgd in litters including at least one halothane-positive reactor. Blood typing was carried out in 533 pigs of four different lines of breeding company Cofok in Oosterhout and was found to be very successful (using the linkage groups) in identifying the heterozygotes. In 15.5 per cent of the offspring, it could not be stated whether the genotype was HalNN or HalNn. This was due to the fact that in these Nn x Nn matings the two haplotypes of one or both parents were identical. In this population, the haplotype PhiB-Po2S-PgdB was strongly (72-89 per cent) linked to the Haln-allele.

An international parentage and identification panel for the domestic cat (Felis catus).

Seventeen commercial and research laboratories participated in two comparison tests under the auspices of the International Society for Animal Genetics to develop an internationally tested, microsatellite-based parentage and identification panel for the domestic cat (Felis catus). Genetic marker selection was based on the polymorphism information content and allele ranges from seven random-bred populations (n = 261) from the USA, Europe and Brazil and eight breeds (n = 200) from the USA. Nineteen microsatellite markers were included in the comparison test and genotyped across the samples. Based on robustness and efficiency, nine autosomal microsatellite markers were ultimately selected as a single multiplex 'core' panel for cat identification and parentage testing. Most markers contained dinucleotide repeats. In addition to the autosomal markers, the panel included two gender-specific markers, amelogenin and zinc-finger XY, which produced genotypes for both the X and Y chromosomes. This international cat parentage and identification panel has a power of exclusion comparable to panels used in other species, ranging from 90.08% to 99.79% across breeds and 99.47% to 99.87% in random-bred cat populations.

The role of A-O-incompatible blood transfusions in porcine orthotopic liver transplantations.

The consequences of administrations of A-O-incompatible blood transfusions during porcine orthotopic liver transplantations (OLT) are described. Two series, both subjected to the same standard procedure except for the administration of compatible or incompatible blood, are compared. The striking differences in peroperative and direct post-operative morbidity, mortality, and causes of death between the two series are presented. Although not generally applied, blood transfusions in experimental surgery should undergo the same precautionary measures as blood transfusions in humans.