I . Effects of feeding liquid milk-substitute to young calves either by nipple-pail or open-bucket o n the rumen by-pass and on the rate of passage were studied.z. Sixteen Holstein calves, aged I week initially, were used in three experiments in which calves were slaughtered after they were given liquids (milk-substituteand water) containingchromic oxide and SrCI, .6H,O as a tracer either by the nipple-or bucket-feeding method, and the distribution of tracers to the rumen, abomasum and the lower alimentary tracts was examined.3. When the liquid milk-substitute containing tracers was given by the nipple-or bucket-feeding method to calves having been trained to the corresponding procedures for the preceding I week, most of the tracers was directed into the omasum and abomasum. There seemed no difference in the functioning of oesophageal groove closure between the two feeding procedures. Even when the liquid milk-substitute containing tracers was given by the nipple-or bucket-feeding method to calves which had been accustomed to different procedures for the preceding week, the majority of tracers were found in the abomasum immediately after administration, though a slightly greater proportion of the tracers entered the reticulo-rumen.4. Continuing bucket feeding of liquid milk-substitute effected an efficient closure of the oesophageal groove at least up to 16 weeks of age. After calves were accustomed t o consume liquid milk-substitute from the bucket from I to 4 weeks of age, drinking warm water from the bucket also caused efficient closure at least up to 16 weeks of age.5. When tracers were administered with warm water, Cr,O, and strontium, especially the latter, transferred much more rapidly to the lower gut than when they were administered with liquid milk-substitute, probably reflecting the curd formation of the milk-substitute in the abomasum. When liquid milk-substitute with tracers was fed by the bucket-feeding method, Sr transferred more rapidly to the lower gut than when the milk-substitute was fed by the nipple-feeding method, indicating that the feeding procedure of liquid milk-substitute has a n apparent effect on the rate of passage.Milk-substitutes have been used in many intensive farms as the means of reducing cost of rearing calves. Feeding procedures of the liquid milk-substitute are divided into two main classes : the nipple-feeding method and the bucket-feeding method. The nipple-feeding method has been considered to be more adequate for young calves from the physiological aspect than the bucket-feeding method, in view of earlier work which showed that the reflex closure of the oesophageal groove depended on the stimuli associated with sucking milk from a teat (Wise & Anderson, 1939) or on the posture of calves while sucking (Wise et al. 1942). However, the bucket-feeding method has been adopted by large numbers of Japanese farmers because of its simplicity.Subsequently, Hegland et al. (1957) observed a complete closure of the oesophageal groove of calves during 6 weeks after birth, independe...

MG exposure significantly increases the long-term risk of death from respiratory cancer and chronic bronchitis/emphysema. The Okuno-jima MG Index may be a useful indicator for estimating cumulative MG exposure.

1. Nutritional effects of a diet consisted of corn , soybean meal and other common feedstuffs by-passing the rumen of calves were compared with those of the same diet undergoing the rumen fermentation . 2. An equal amount of the diet given daily to two groups of seven Holstein calves each from 7 to 12 weeks of age , eigher in a pelleted form to suffer the rumen fermentation ('dry-fed' group; DFG) or in liquid suspension from a bucket to avoid the rumen fermentation ('liquid-fed' group; LFG) .At 87 days of age, two calves each in one group were sacrificed , and jugular blood samples were taken from the remaining calves. 3. The quantity of ammonia in the rumen was similar in both groups, but that in the large intestine tended to be greater in DFG than in LFG. The quantity of volatile fatty acids (VFA) in the rumen was greater in DFG than in LFG, but their quantity in the large intestine tended to be greater in LFG than in DFG. 4. In DFG, the molar proportion in the VFA of acetic acid was higher, and that propionic and butyric acids was lower in large intestine than in the rumen .In LFG, the molar proportion of acetic acid was higher, and that of butyric and isobutyric acids was lower in the rumen than in large intestine. 5. The plasma glucose was at the same level in both groups. Plasma levels of ketone bodies (P<0.01) and glycogen content in liver (P<0.05) were significantly lower in LFG than in DFG. 6. Plasma levels of triglycerides and phospholipids were significantly higher in LFG (P <0.05).The content of total lipids in liver was significantly higher in LFG than in DFG (P< 0.05). Total lipids in liver of LFG calves had significantly increased lipid fractions of triglycerides, total cholesterol and free fatty acids (P<0.05), and contained larger amounts of highly unsaturated C18 fatty acids. 7. Riboflavin levels in blood and liver were similar in both groups.The rumen plays a very important role in the nutrition and the metabolism of ruminant animals. In our previous report1) , it was described that body-weight gains were much depressed when calves were given a diet consisted of corn, soybean meal and other common feedstuffs in liquid suspension to avoid the rumen fermentation. Apparent digestibilities of crude protein and nitrogen-free extracts were lower when the same diet was introduced into the rumen and suffered the fermentation in it. However, the digestibility of crude fibre was not lowered in calves receiving liquid feed, and these calves had more developed caecum and large intestine as well as less developed rumen and omasum than calves receiving dry feed, predicting some shifts in the

1. Studies were done on the effects of giving calves two types of concentrate diet, both in a liquid form from an open pail or in a dry pelleted form, on the closure of oesophageal groove, body-weight gains and the digestibility of rations. 2. Twenty-four Holstein calves were used in an experiment by dividing into two groups of twelve calves each. The 'dry-fed' group (DFG) was given a pelleted concentrate, F1, from 25 to 42 d of age, and then given another type of pelleted concentrate, F2, from 43 to 87 d of age, and again given F1 from 88 to 112 d of age. The 'liquid-fed' group (LFG) was given from a pail a liquid suspension of the equivalent amount of the same concentrates as those fed to DFG calves, for the same periods. F1 contained skim milk and glucose with lower levels of maize and soya-bean meal than F2 which did not contain skim milk or glucose; F1 and F2 were both supplemented with 10 g methionine/kg and also supplemented with lysine at 5 and 10 g/kg respectively. All calves were allowed free access to roughage, and digestibilities were measured at 12 and 16 weeks of age. 3. Wet weights of reticulo-rumen and abomasal tissues (% whole stomach weight) were respectively 69.8 and 17.6 in DFG, and 59.0 and 26.4 in LFG at 42 d of age; at 87 d of age, the corresponding values were 68.0 and 16.3 in DFG, and 52.8 and 36.6 in LFG, and further, LFG had significantly more developed caecums and large intestines as well as significantly less developed reticulo-rumens and omasums than DFG. 4. Free amino acid patterns in plasma did not vary in DFG, but varied in LFG in response to the change in diet from F1 to F2 and to the difference between diets in lysine supplementation. 5. Feeding F1 in a liquid form and F2 in a dry form significantly improved calf gains. The intake of roughage in DFG exceeded that in LFG especially when F2 was fed. 6. The digestibility of diethyl ether extracts did not vary with feeding procedures, but that of crude protein (nitrogen x 6.25) was significantly higher in DFG independent of the type of diet. Digestibilities of dry matter and N-free extracts were significantly higher in LFG for F1, while higher in DFG for F2. The digestibility of acid-detergent fibre did not differ significantly between groups at 12 weeks of age, but was significantly higher in LFG at 16 weeks of age, suggesting a possible compensatory contribution of the large intestine to the digestion of fibre in LFG. 7. The efficiency of liquid feeding of a concentrate diet to ruminants compared with that of dry feeding is discussed.