W. S. Ferguson

The teart pastures of Somerset: I. The cause and cure of teartness

The scouring of cattle and sheep caused by the teart pastures of central Somerset is due to the presence of molybdenum in the herbage in amounts varying from about 20 to 100 parts per million in the dry matter. The scouring can be prevented and cured by feeding or drenching with copper sulphate. A daily dose of 2 g. copper sulphate for cows and 1 g. for young stock, is sufficient to cure and prevent the scouring on very teart land. Less copper sulphate may be enough on mildly teart land.

The chemical composition of grass silage

A short account is given of the main changes which take place during the ensilage process. Details are given of the methods of analysis used in examining samples of silage for p H, crude-protein, volatile base, amino acid, lactic acid, total volatile acid, acetic acid and butyric acid contents. The results of the examination of 293 samples of silage are discussed. Of these 258 were made from grassland herbage, 24 from silage crops, 9 from sugar-beet tops, and 2 from potatoes. The silages were made in towers, wood-lined pits, and a small number in stacks or clamps. The samples are divided up into those made by the ordinary process, with added molasses, with added whey, with moderate amounts of mineral acid with or without molasses, and with mineral acids added in amounts sufficient to bring the mass rapidly to a p H of 3·0–4·0—the A.I.V. process. For comparative purposes the silages made by these processes have been divided, within each process, into groups of varying p H. reaction.

The effect of nitrogenous fertilizers on the non-protein nitrogenous fraction of grassland herbage

The non-protein nitrogenous (NPN) fraction of grassland herbage given a range of repeated nitrogenous fertilizer treatments has been examined. The herbage was intended for conservation and the treatments were 0, 2, 4, and 6 cwt. ‘Nitro-Chalk’ per acre per cut, applied early, after cutting, and late, 10–14 days before cutting.

The losses of dry matter and digestible nutrients in low-temperature silage, with and without added molasses or mineral acids.

A series of experiments designed to measure the losses in dry matter and nutrients in different types of silage are described. These extend over a period of 4 years. The ordinary or low-temperature process (maximum temperature 80–100° F.) is described either with or without added molasses or whey solutions, and is compared with processes in which solutions of mineral acids are added. The A.I.V. process of Virtanen, in which the acidity of the mass is reduced rapidly to p H. 3·0–4·0 by the addition of a mineral acid solution, is considered in detail.

The time of cutting hay, and the losses entailed during haymaking

Experiments have been carried out from 1930 to 1935, to investigate the composition, digestibility and yield of meadow hay cut at a normal time, and also of hay cut some 3–5 weeks earlier. Due consideration has been given to the “aftermath” growth occurring on the areas cut for the early hay between the times of cutting of the early and ordinary hay. As was expected, the early hay, being less mature, was of better composition and digestibility than the ordinary hay. The average crude protein contents were 12·2 and 7·9 per cent of the dry matter respectively. The yield data, average of 5 years, are summarized below, stated as lb. per acre, the early hay values including the aftermath yields.

The chemical composition of bracken ( Pteridium aquilinum )

Samples of bracken were taken at fortnightly intervals from June to November at two centres. These were separated into leaf and stem and analysed. Larger samples were treated for the preparation of proteins and sugars by passing the bracken through a roller-mill, precipitating the protein with acid and concentrating the juice for sugars. Chemical composition . The main points in the analyses of the whole plants were as follows, all figures quoted being on a dry-matter basis: (1) The crude and true protein contents of young bracken in early June were high, 21 and 18%, but these fell rapidly to 10% in mid-July and finally to 3% in October. (2) The lignin content was high throughout, rising from almost 20% in young bracken to 34% in the nearly dead material. (3) The cellulose content followed the lignin content. (4) In July and August the bracken contained about 10% of total sugars. A rapid fall occurred in October, and the final samples contained very little sugars.

Marrow-stem kale silage.

Kale silage was made in five large silos and the losses of dry matter and kale constituents determined. The losses of dry matter averaged 33%, of N-free extract 41% and of crude protein 34%. The percentage losses are higher than with wellmade grass silage, but, nevertheless, the yields of silage (and animal nutrients) per acre compare very favourably with those of other crops, including grass. Inclusion of straw in kale silage did not reduce losses of dry matter; it merely reduced slightly the quantity of water lost.