Identification of Mycoplasma gallisepticum and M. synoviae by flow cytometry

Immunofluorescence and flow cytometric methods were examined to detect and distinguish Mycoplasma gallisepticum and M. synoviae. The procedure employed 24-hr broth cultures of each organism, direct immunofluorescence staining with either homologous or heterologous antiserum, and analyses by flow cytometry. The organisms were distinguishable on the basis of fluorescent profiles when stained with the appropriate antiserum.     

A systems analysis of the guyanese livestock industry

This paper attempts to contribute to the capability for livestock sub-sector analysis. A model structure which offers potential for evaluation of changes of policy, available production technology, or factor and product market conditions is described. The structure integrates a multi-year biological cattle simulator with a price endogenous model of the cattle sub-sector to yield a model designed to simulate aggregate behaviour of profit maximising cattle producers interacting through competitive factor and product markets. The general model structure is specified to reflect conditions in Guyana, South America. The model, specified for Guyanese conditions, is used to evaluate the probable impact of a number of technical and economic changes in the system.     

Identification of hindleg lameness

The use of markers placed over the tuber coxae on each side of a horse to aid identification of the relative movement of these structures at the trot, for teaching and research purposes, is described. In each case of hindleg lameness studied, the tuber coxae on the lame side showed a consistent increase in vertical displacement relative to that of the contralateral limb, and a characteristic pattern of movement throughout the stride irrespective of the site or cause of pain.     

Harvest-pruning and trellising of ‘Sultana’ vines. I. Effects on yield and vegetative growth

Yield reductions averaging 10% are reported from 2 experiments in which ‘Sultana’ vines were continuously harvest-pruned for 11 and 9 years respectively. Over the period of the study there was no evidence of the yield reduction increasing with time.Differences between treatments in bunch number, berry weight and total soluble solids did not account for the reduction in yield. However, berry number per bunch was consistently, if not always significantly, lower on treated vines. Harvest-pruned vines had lower pruning-weights than the control vines.Increases in trellis width from 0.30 to 0.45 m to 0.90 m generally led to increases in yield caused by increases in bunch number. A 0.30 m wide T-trellis, with foliage wires added to support the shoots vertically to a height of 2 m, also gave yield increases over the standard 0.30 m trellis in most seasons. Harvest-pruned vines on the 0.90 m wide trellis gave similar yields to control vines on the standard 0.30 m trellis.     

Harvest-pruning and trellising of ‘Sultana’ vines. II. Effects on early spring development

The yield reductions associated with the harvest-pruning system of drying sultanas could not be attributed to a consistent effect on any of the components of yield. However, in several experiments berry number per bunch was reduced on harvest-pruned vines and in others there was a trend in this direction. The cause of this reduction appeared to be flower number per inflorescence. A hypothesis is proposed to explain the effect.Harvest-pruning and associated trellising treatments had only small effects on bud-burst and early shoot growth.     

Differentiation of infectious laryngotracheitis virus strains using restriction endonucleases

Strains of infectious laryngotracheitis virus (ILTV) were examined using an indirect immunofluorescent test (IIF) and with restriction endonucleases for detecting intratypic differences. Electrophoretic analysis of ILTV DNA fragments cleaved with restriction endonuclease Hind 111 clearly distinguished between strains. The IIF test did not discriminate between strains. A molecular weight estimate of ILTV DNA was made by summation of restriction endonuclease fragments cleaved with BamH1 (102.1 X 10(6)) and Hind111 (97.35 X 10(6)). Differences between the estimates may indicate the presence of submolar fragments.