This group, which is concerned with the applications of mathematics to agricultural science, was formed in 1970 and has since met at approximately yearly intervals in London for one-day meetings. The thirty-fifth meeting of the group, chaired by Dr David Parsons of Silsoe Research Institute, was held in the Kohn Centre at the Royal Society, 6 Carlton House Terrace, London on Friday, 11 April 2003 when the following papers were read. [PUBLICATION ABSTRACT
The effect of base composition biases on codon usage patterns was investigated in the goat species Capra hircus, using custom-designed computational tools available within the public domain. Nucleotide frequencies were nearly equal and a slight increase of adenine-thymine (AT) over guanine-cytosine (GC) was detected throughout the dataset. However, this increase showed no influence on the bases at the third codon position (N3). C3 and G3 were found more often than A/T3, suggesting that there was a small or almost no influence of the general base composition on the N3 base composition. To understand more and analyse in-depth influence and interactions between base compositions and codons, further relative synonymous codon usage (RSCU) was investigated. Amino acid usage and the correlation between its usages were also investigated, using both basic sequence analysis and statistical analysis means (measures of correlation). These analyses were utilized to probe whether there were correlations between genes, genomic characteristics and their function. Genes with high GC and those with low GC were also investigated to see to what extent how a gene functions could influence its sequence structure and impose certain structural modifications. This investigation may shed light on many genomic features of Capra hircus genes and would be of significance for future biotechnology/research projects considering Capra for transgenic and advanced genomic initiatives.
The marginal winter pastures of reindeer and caribou (Rangifer tarandus) in Arctic and sub-Arctic areas are assumed to be nitrogen- and mineral-poor. Reindeer eat a mixed diet consisting of nitrogen deficient lichens and a wide variety of vascular plants in winter. Some reindeer populations manage to maintain carcass mass outside the growing season and very little is known about the ability of reindeer to utilize vascular plants in this season. The chemical composition and in vitro digestibility of 17 species of vascular forage plants and one species of moss collected mid-winter from beneath the snow at an inland winter pasture in northern Norway were determined. Wintergreen parts of graminoids had a high content of crude protein (72-108 g/kg dry matter (DM)) and water-soluble carbohydrates (98-167 g/kg DM) and were highly digestible (50-65 % DM) compared with the withered parts of the plants (27-53 % DM). The digestibility of both shrubs and graminoids was inversely related to content of cellulose and lignin, but positively correlated with increasing contents of water-soluble carbohydrates. Shrubs were relatively calcium-rich (3.6-6.1 g/kg DM) while wintergreen graminoids contained up to 10.0 g/kg DM of potassium, 1.5 g/kg DM magnesium and 2.1 g/kg DM phosphorus. The present study demonstrates that the wintergreen parts of several species of vascular plants are nutritious, containing high levels of nitrogen and minerals, and that they are highly digestible to reindeer in winter. Vascular plants may, therefore, be more important to reindeer and caribou in winter than previously realized.