A preliminary report on the occurrence of maedi‐visna in sheep in Morocco

Summary

A small scale serological survey for antibodies to maedi‐visna virus among 15 flocks of sheep in Morocco revealed the infection in one flock. Infection appeared to be related with imported sheep. In addition, two abattoir surveys yielded, 0.1% lungs with gross and histological lesions suggestive of maedi.     

Heritability of plasma cholinesterase activity in inbred mouse strains

The activity of cholinesterase was measured in the plasma of 543 mice of both sexes from 23 inbred mouse strains. Differences between strains were highly significant. The heritability of this characteristic was 0.70 in females and 0.67 in males.     

Distribution and phylogeny of Potamophila parviflora R.Br. a wild relative of rice from eastern Australia

Potamophila parviflora is a wild relative of rice from Eastern Australia. The species was found in the Richmond, Clarence, Macleay and Hastings River systems of northern New South Wales. Existing populations had wider leaves (10–15 mM) than those previously reported (4–6 mM). This species and North American wild rice, Zizania palustris were investigated as genetic resource for rice improvement. Both species, Potamophila , and Zizania , occur in colder climates than rice (Oryza sativa). Sequencing of the ITS1 of the ribosomal genes of these two species indicated that Zizania and Potamophila were more closely related to each other than either was to Oryza sativa. Potamophila has a similar number of chromosomes (n=12) and a greater sequence homology to rice and may thus be a better source of useful genes for rice improvement.     

Prevalence of antibody to rotavirus in Moroccan cattle

A serological survey was carried out in order to determine the prevalence of antirotavirus antibodies in Moroccan cattle under different management conditions. From the 493 serum samples examined, 325 (65.9%) were found positive, using a counter-immunoelectroosmophoresis technique. Animals of indigenous breed coming from farms with rapid turnover or large number of animals, or having frequent contacts with imported cattle, had a higher rate of seropositivity; however, positive sera were also found in cattle from small farms in remote areas, showing that rotavirus infection is ubiquitous in that country. No relationship was found between the prevalence of anti-rotavirus antibodies and the frequence of calf diarrhoea. The percentage of seropositive animals in a herd has to be considered as an epidemiological indicator.