J. Margaret Eadie's scientific contributions

Publications (6)

Article
Synopsis In January 1956 a visit was made to North Ronaldshay, one of the Orkney Islands, to examine the rumen ciliate protozoa of the seaweed-fed native sheep. Rumen material from thirteen sheep was examined and the ciliate species identified. The numerical ratio of holotrich to oligotrich ciliates appeared to be much the same as in the hay-fed sh...
Article
SUMMARY : Many sparingly water-soluble neutral substances, including several indole derivatives, will quickly kill and often disintegrate washed living rumen ciliates at 85-39', when acting at or near the saturation point (0-002-0.1 M) in a phosphate + acetate buffer at pH '7. The toxic compounds are mostly readily soluble in light petroleum. Organ...
Article
When metabolizing glucose or other fermentable sugar in vitro at a temperature 8-12" below the normal rumen temperature, three species of rumen holotrich ciliates were liable to exhibit highly abnormal appearances which were not seen at 35-38'. These abnormal appearances consisted essentially in a contraction and fusing together of the bulk of the...
Article
Hogg and Elliott1 noted that indole and skatole were both highly toxic towards the aerobic free-living ciliate Tetrahymena pyriformis. A concentration of 0.01 per cent of indole, for example, killed all organisms in a vigorous culture in two hours, but these workers made no mention of any characteristic change in appearance of the cells. We have no...

Citations

... North Ronaldsay sheep fed a diet containing L. digitate seaweed had rumen microbial communities that differed greatly in ciliate protozoa (e.g., Dasytricha ruminantium species) and bacterial populations (Streptococcus bovis, Selenomonas ruminantium, Butyrivibrio fibrisolvens, and lactate-utilizing bacterial species) compared to those on a pasture-based diet (Greenwood et al., 1983;Orpin et al., 1985). This is similar to findings of Eadie (1957) and Mitsumori et al. (2012) who reported decreased relative abundance of methanogen, protozoa, and fungi populations when sheep and goats were fed diets containing brown seaweed (Laminaria sp.) or BCM (0, 0.5, 2.0, and 5 g/100 kg BW) supplementation. These results, however, are inconsistent with other data (Belache et al., 2016). ...
... Tetrahymena pyriformis, Isotricha, Dasytricha, and Ophryoscolex, leading to cell immobility and drastic disintegration (Hogg and Elliott, 1951;Eadie and Oxford, 1954). However, most of the J o u r n a l P r e -p r o o f studies were concentrated on pure isolates, and the roles of skatole on microbial community (in intestines, swine manure, and WWTPs) composition, assembly, and functions remain unclear. ...
... There are mixed reports on the effects on rumen protozoa. The early study of Eadie et al. (1956) showed that certain terpenes and other substances present in plant material had marked toxic properties towards rumen protozoa. However, ruminal protozoa counts were not affected when a blend of EO was used in vitro (McIntosh et al. 2003) and was fed to dairy cows @750 mg/day (Benchaar et al. 2007). ...
... De faunation also can be achieved by emptying the rumen, carefully washing the ruminai mucosa and treating the digesta by heating or freezing before reintroducing it into the rumen. Heating ruminai contents to 50°Cfor 15 min kills holotrich ciliates (Eadie and Oxford 1957), whereas freezing then thawing the digesta eliminates all protozoa (Jouany and Senaud 1979). Gossypol, a naphthalene derivative found in cottonseed, has been shown in vitro to kill many of the protozoa but to main tain holotrichs alive ( Ismartoyo et al. 1994). ...
... However, this problem seems to be mitigated by the ibex's strategy of retreating into steep rock walls that are inaccessible to terrestrial predators (Kohlmann, Muïler & Alkon 1996; Toı¨goToı¨go 1999). Second, and presumably more important, experimental evidence from cattle and sheep shows that lowered T r significantly impairs fermentation (Gengler et al. 1970 ), disturbs the ruminal microfauna (Eadie & Oxford 1955) and leads to increased food requirements (Bhattacharya & Warner 1968). Therefore, T r must not fall drastically over long periods of time to guarantee the animal's survival. ...