350
ABSTRACTS
A quantitative study of vitamins in the rumen contents of sheep and cows
fed on vitamin low diets. L. W. McELROY and HAROLD GOSS (1940-
41). (1) Riboflavin and Vitamin K. J. Nutrition 20, 527.
(2) Vitamin B 6 (Pyridoxine). J. Nutrition, 20, 541.
(3) Thiamin. J. Nutrition 21, 163. (4) Pantothenic
acid. J. Nutrition, 21, 405
T HE authors have pointed out that owing to the lack of more recent knowledge
in the field of the complex nature of B vitamins and also to the lack of well-
defined methods of assaying, the problem of vitamin B requirements of ruminants
was much handicapped. Attempts have, therefore, been made, in these papers to
establish the synthesis of (1) riboflavin and vitamin K, (2) vitamin B 6 (pyridoxine), (3)
thiamin and (4) pantothenic acid in the rumen of sheep and cows, one of the cows having
a permanent rumen-fistula.
For riboflavin assay a modification of the method of Jukes [1937], for vitamin K
assay the method of Almquist and Klose [1939], for vitamin B 6 assay a modified method
of Dimick and Schreffler [1939], for thiamin assay the method of Jukes and Heitman
[1940] and for pantothenic acid assay the 'filtrate factor' method of Jukes [1937]
were employed.
(1) On a deficient ration with less than 0.3 microgram of riboflavin per gram, the
rumen contents of sheep contained 33 micrograms and of fistulated cow 25 micrograms
of riboflavin per gram. The riboflavin contents of milk produced was 16 to 18 mg.
per day, a figure rather too high as compared with maximal intake of only 1.8 mg. per
day in the feed. Though the experimental ration of the cow was practically free from
vitamin K, the rumen proved to be a considerable rich source of it.
(2) On a deficient ration containing between 1 and 1.5 micrograms of vitamin B 6
per gram, the dried rumen and reticulum contents of four sheep and a fistulated cow
contained approximately 10 micrograms and 8 micrograms of vitamin B 6 per gram
respectively, the amount in milk being in no way less than that of cows on normal
feed.
(3) The dried rumen and reticulum contents of sheep fed on deficient ration con-
raining less than 0.4 microgram of thiamin per gram contained approximately 7 micro-
grams of thiamin per gram, but, contrary to expectation, the dried rumen contents of a
fistulated cow yielded no more thiamin than was present in the basal diet, while the
analysis of milk showed an appreciable amount of the vitamin. Experimental results,
however, showed that thiamin could be obtained from the rumen of the non-fistulated
cow on a deficient ration, which suggested that the presence of an artificial opening in
the rumen might have altered the physiological functions in such a way as to render it
unfavourable for the growth of rumen organisms, capable of synthesising thiamin.
(4) Pantothenic acid of the rumen and reticulum contents estimated on dry matter
basis per gram was 70 micrograms in the case of sheep, 61 micrograms in the case of non-
fistulated and 94 micrograms in the case of fistulated cow, the animals in all cases being
on a vitamin B-complex deficient diet with utmost maximum availability of even less
than 2.8 micrograms of pantothenic acid per gram. Dried skim milk from the milk
of the fistulated cow showed an excretion of 46 micrograms of pantothenic acid per
gram.
In the light of the aforesaid observations, it seemed to the authors that the differen-
tial passage of materials from the rumen as a possible cause of increase in the vitamin
potency of its contents was inadequate to explain in the face of such high increase.
The authors therefore concluded that these vitamins were truly synthesised in the
rumen of these animals by the bacterial flora and as such were" not dietary essentials
in their ration. [A. K. P.]
Studies on Listerella infection in sheep. H. E. BRISTER and L. H,
SCHWARTE (1939). J. Infec. Dis. 64, 135-44
T HE authors describe the isolation of Listerella (ovis) from brain tissue of sheep
in two field outbreaks of a disease characterized by disturbance of the central
nervous system. Histological examination of brain and spinal cord of affected cases