Analysis of faeces for titanium by the X-ray fluorescence technique is shown to be a rapid and reliable method of determining soil content of faeces. Ingestion of soil by dairy cows has been followed monthly on a herd basis over the 1967-8 season on a limited number of town supply herds in the Kaitoke and Wairarapa districts, and on Nos. I, 2, and 3 Dairy Units at Massey University. Mean soil ingestion per cowan the private farms ranges from about 400 to 700 lb per year. Soil ingestion at Massey ranges from about 400 Ib per year on the lighter-stocked No.1 Unit (town milk supply) to over 1.000lb of soil per cow per year on the heavilystocked No. 3 Unit. Animals wintered on paddocks on No. 3 Unit ingest more soil than do the platform-wintered herd. Ingestion of soil on an individual animal basis at No.5 Dairy Farm at Ruakura Agricultural Research Centre was followed weekly from individual faeces samples collected over the 1965-6 season. Soil ingestions range from approximately 200 to 800 lb per cow per year, and can differ by a factor of two for different animals in the same herd. Evidence is presented to demonstrate that some twins may show inherited tendencies to either low or high soil ingestions. Soil content of faeces may provide some measure of the grazing behaviour of an animal. While yearly intakes of soil can reach approximately 1,000 lb, this is still less than about 2% of the weight of fresh pasture consumed. The possible importance of ingested soil as a source of DDT and micro elements for animals is discussed.

Two sheep were drenched each with 100 g of soil containing approximately 1 mc each of 60Co, 540Mn, 75Se, and 65Zn. Activities of these isotopes in blood, urine, and faeces were monitored at intervals over a lO-day period by gamma-ray spectroscopy. At the end of this period the animals were killed and a range of hard and soft tissue samples was taken for analysis. From the data obtained on blood and tissue samples taken at time of death, and from urine samples over the lO-day period, amounts of isotopes absorbed by the animals and amounts of isotopes originally held on the ingested soil were compared. The amounts of the isotopes absorbed by the animals from the soil, expressed as a percentage of an isotope held on the soil, were approximately: 75Se, 34 percent; 65Zn, 14 percent; 60Co, 1 percent; MMn, 0.4 percent.

No abstract

Establishment of 15 lines of legumes on two soils with differing nematode populations was studied under greenhouse conditions. Kokatau silt loam (yellow-grey earth) contained only Heterodera trifolii, but Egmont brown loam (yellow-brown loam) contained both H. trifolii and Me/oidogyne hap/a. Seven lines of white clover, two of red clover, two of subterranean clover, two of lotus, and two of lucerne were sown into unsterilised soil or soil sterilised with methyl bromide which served as control. Yields and nematode infestations were measured 20 and 33 days after sowing.The yields of all seven lines of white clover, representing four varieties, and the two lotus varieties were seriously reduced by both H. trifolii and M. hap/a. Subterranean clover was tolerant to attack, but yield of red clovers was reduced by M. hap/a. College glutinosa lucerne tolerated invasion by both nematodes, but 'Wairau' was susceptible to M. hap/a attack. ' 81

Clover and ryegrass samples from two areas grazed with 15 and 22 sheepfha contained approximately 10 and 25% of soil respectively, and mean soil contents of faeces from the two groups of sheep were 37 and 69% respectively. The concentration of a number of clements was five times or more higher in grazed pasture than in ungrazed. As soil is usually a component of grazed herbage, analysis of clean herbage will give only the minimum element intake of animals.'