Environmental requirements of three threatened plants on limestone glades in Southern Missouri

Information on critical area required to ensure the long-term survival of plant populations is lacking for the development of conservation policy. Here we examine the relative importance of critical area and environmental factors to the distribution of a threatened perennial Penstemon cobaea, biennial Stenosiphon linifolius, and annual Centarium texense on limestone glades in southern Missouri. Two of three plants show a glade-size dependent distribution: P. cobaea colonised large and S. linifolius small glades. C. texense successfully colonised glades of all sizes. Environmental requirements of populations of the three species differed, but overlap in range was evident. Diffuse competition may account for the observed patterns in distribution but further study is required. In the interim, we suggest that a useful approach for developing a conservation policy for natural plant communities is the intensive study of a few plant species with contrasting life-history strategies.     

Bovine plasma beta-mannosidase activity and its potential use for beta-mannosidosis carrier detection.

Plasma beta-mannosidase activities were determined for Salers cattle from 8 herds as an evaluation of this method for detection of beta-mannosidosis heterozygotes. Several biological factors, such as age, gender, herd, and risk of being a beta-mannosidosis carrier, were considered in this study. The mean enzyme activity for obligate heterozygotes (n = 8) was 55 U/ml (range = 43-65 U/ml), which was 59% of the mean enzyme activity for cattle that were low risk for being a carrier. These data indicate that bovine beta-mannosidosis is characterized by a gene dosage effect. The analytical and biological variation of plasma beta-mannosidase activity that was observed necessitates limiting the test to adult fullblood/purebred Salers cattle within a herd. Plasma beta-mannosidase analysis provides important information for intraherd selection of Salers cattle that are heterozygous for beta-mannosidosis.     

Investigations into the toxicity of Echium plantagineum in sheep: 1. Field grazing experiments

A field grazing trial was undertaken to monitor the health and production of crossbred sheep grazing pasture where Echium plantagineum constituted a considerable proportion of the available forage. The trial, conducted for 19 months over successive grazing seasons, demonstrated a significant difference in production, with sheep on the E. plantagineum pasture being lighter and growing less wool compared with sheep on Echium-free pasture. No mortalities involving pyrrolizidine alkaloid poisoning were recorded in sheep grazing E. plantagineum, although there was histological evidence of moderately severe liver damage associated with high liver copper concentrations in at least one sheep following the grazing of large quantities of the plant.     

A Report on the Sexual Cycle in the Kudu Bull Tragelaphus Strepsiceros Pallas and a Description of an Inter-Sex

The tendency of trauma to the eye, especially in the cases of infected perforating wounds or of parasitic infections, to involve all structures of the eye, is outlined and the need for surgical treatment is discussed. Difficulties and problems in operative procedures arising from the varied manifestations of panophthalmitis, particularly with regard to anaesthesia, immobilization, excision and resection of tissues, drainage and postoperative dressings, and the methods of overcoming them, are described on the basis of nineteen surgical cases.