Norikatsu Miwa

Paternity discrimination and inter-group relationships of chimpanzees at Bossou

A small group of wild chimpanzees at Bossou, southeastern Guinea, is semi-isolated, occupying a home-range which is several kilometers from those of other groups. The group has had only one adult male since 1985, raising the probability of inbreeding. Direct observation suggests that this male was the father of all infants born in the group since 1985. In 1991 individually identified samples of food wadges, hair, and feces were collected from most of the group members. These samples were analyzed using GT dinucleotide repeat polymorphisms to determine familial relationships. The genetic analysis revealed that the resident adult male was the probable father of only three out of the four infants analyzed. It is suspected that an adult male from a neighboring group was the father of the fourth infant, born in late 1986 or early 1987.

Yersinia pseudotuberculosis infection in breeding monkeys: detection and analysis of strain diversity by PCR

In the last three decades, several monkeys reared in outdoor/indoor–outdoor breeding colonies and cages of the Primate Research Institute, Kyoto University, died of yersiniosis caused by Yersinia pseudotuberculosis, necessitating introduction of a method to detect the bacteria rapidly and thus allow preventive measures to be undertaken. A rapid nested polymerase chain reaction (PCR) method for identification of Y. pseudotuberculosis in fecal samples and a random amplified polymorphic DNA (RAPD)‐PCR approach for distinguishing between bacterial strains were therefore developed. Yersinia pseudotuberculosis isolates from monkey specimens were found to be classifiable into several types. To determine the source of infection, hundreds of fecal samples of wild rats, pigeons, and sparrows were collected from around the breeding colonies and cages, and subjected to PCR analyses. Yersinia pseudotuberculosis was detected in 1.7% of the fecal samples of wild rats. The DNA fingerprints of the bacteria revealed by RAPD‐PCR were the same as that of one strain isolated from macaques, suggesting the wild rat to be a possible source of infection.

Autoimmune hemolytic anemia (AIHA) in an infant rhesus macaque (Macaca mulatta)

Autoimmune hemolytic anemia (AIHA) is a disorder associated with the destruction of red blood cells (RBCs) by autoantibodies. We report a rare case of AIHA in an infant rhesus macaque (Macaca mulatta) which received a continuous administration of four drugs, a dopamine agonist, dopamine receptor inhibitor, and two Γ‐aminobutyric acid receptor inhibitors into the brain during the course of neurophysiological experiments. The main clinical findings were severe anemia and splenomegaly. Hematological and serological examinations revealed the appearance of peripheral erythroblasts and autoantibodies against RBCs. Medical treatments, including washed RBC transfusion and corticosteroids, transiently improved the animals anemia, but euthanasia was decided on 331 days after the start of the experiment. The pathological findings revealed severe anemia, splenomegaly, and extramedullary hematopoiesis in the liver and kidneys. These findings and the clinical course suggest that this anemia was a warm‐antibody type of AIHA induced by the administration of the drugs for the neurophysiological experiment.