It is well known that oxidative rancidity takes place more rapidly in cooked meat than in raw meat. In order to elucidate this reason, the effect of heat-treatment on the amount of free lipids released from isolated mitochondrial fraction and their fatty acid composition has been investigated in the present work. The amount of free lipids extracted with petroleum, ether from isolated mitochondrial fraction of chicken muscle tissue (M. pectoralis profundus), their phospholipids and free fatty acids, and polyunsaturated fatty acids in the free lipids. were found higher in heated and overheated mitochondrial fractions than in unheated one. Judging from the above results, one of the reasons why oxidative rancidity is more accelerated in cooked meat than in raw meat seems to lie in the increase in the amount of phospholipids and of polyunsaturated fatty acids in the free lipids caused by heat-treatment.

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Most of the heme compounds present in skeletal muscle tissue might be myogbin which is considered as one of the principal compounds responsible for the development of oxidative rancidity in meats, however, the relationship between the development of oxidative rancidity and the amount of myoglobin in meat does not seem to have been investigated in detail. Therefore, the effect of metmyoglobin (MetMb) on the development of oxidative rancidity in mitochondrial (M) fraction from chicken skeletal muscle under unheated, heated and over-heated conditions has been investigated. In the unheated M fraction-MetMb system, the addi-tion of MetMb up to 0.2% to the M fraction equivalent to 5 g of wet muscle tissue promoted the development of oxidativerancidity in the M fraction, while the addition of MetMb above 0.2% did not promote the oxidative rancidity any more. In the heated M fraction-MetMb system the development of oxidative rancidity was considerably promoted by the addition of MetMb up to 0.2%, whereas the addition of MetMb above0.2% resulted in a gradual decrease in oxidative rancidity. In both unheated and heated M fraction-MetMb systems containing 0.2% of MetMb and various amounts of M fraction equivalent to 5-20 g wet muscle tissue, the rate of the development of oxidative rancidity increased linearly with the increased amount of M fraction added. From the above results, it was suggested that the ratio of lipid to heme compound may play an important role in the development of oxidative rancidity in cooked meat. In the over-heated M fraction-MetMb system, the addition of MetMb inhibited the development of oxidative rancidity.

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1) Effect of dietary supplement of safflower oil or safflower seed on the hydrogenation of unsaturated fatty acids in the rumen was investigated in a feeding experiment with two goats'. 2) With both treatments, hydrolysis of triglycerides occurred very rapidly in the rumen and unesterified fatty acids increased correspondingly. The more rapid rate of increase in the proportion of unesterified fatty acids was obtained with the feeding of safflower oil than that of safflower seed. 3) The proportion of unesterified C18 decreased until 6 hours after the feeding of safflower oil or safflower seed, while that of unesterified C1=18 increased until 9 and 6 hours, respectively, after the feeding of safflower oil or safflower seed. The greater effect on these fatty acids was observed with the feeding of safflower oil than that of safflower seed.

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The eating and ruminating behaviour of four cows fed hay ad libitum were recorded in order to study the diurnal feeding pattern under tie stall onditions. The animals were fed once a day at 8 a.m. in the first period and at 8 p.m. in the second period, and the feeding patterns were compared. When hay was offered at 8 a.m. mean hay intake was slightly higher (non-significant) and the time spent ruminating was longer (P<0.05) than when offered at 8 a.m. The peaks of time spent eating and the rate of eating were observed immediately after the hay was offered; the pattern of eating, therefore, can be assumed to be governed largely by the time feed was offered, although the effects of the time of day were still recognized. The diurnal pattern of rumination was affected by the time spent eating during each hour throughout the day. The pattern of the total time spent chewing was the highest immediately after the feed was offered and declined gradually during a 24-hour period.

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Adult female sheep were kept in a climatic room at 20°C for 1 week, then exposed to 0°C for 1 week, and re-exposed to 20°C for 1 week. Effects of the temperature shift upon urinary excretion of noradrenaline and adrenaline were determined spectrophotofluorometrically. Rectal temperature, heart rate and respiratory rate were also measured. In sheep exposed to 0°C, urinary excretion of noradrenaline (μg/24 hrs) increased from 18.5 at 20°C to 49.5 at 0°C. The elevated noradrenaline excretion remained high during re-exposure to 20°C. Adrenaline excretion (μg/24 hrs) increased from 3.0 at 20°C to 11.7 at 0°C and returned to 2.8 at re-exposure to 20°C. Normothermia was maintained all through the experimental period. Heart rate (beats/min) increased significantly by cold exposure from 72 to 88, and was 88 by re-exposure to 20°C. Cold exposure had a slight but a significant effect on respiratory rate (breaths/min) which decreased from 20 at 20°C to 14 at 0°C, and by re-exposure to 20°C increased to 29. Cold exposure increased the release of oradrenaline by sympathetic nerve terminals and adrenaline by the adrenal medulla. The elevated activity of the noradrenergic nervous system, when once acclimated, at least partially, to cold, remained high even after returning the animals to thermoneutral environment, while deacclimation to cold occurred in the adrenomedullary system one or two days after the same treatment.

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The aim of this paper is to detect or identify amines and neutral compounds in smell of fresh egg white by thin layer and gas chromatography. These compounds were collected by nitrogen gas permeation method or the extraction method from deproteinized solution of fresh egg white. As amines, ammonia, methylamine, laurylamine, hexylamine, octylamine, 1, 3-diaminopropane, putrescin, cadaverin, ethylenediamine, 1, 6-hexamethylenediamine and monoethanolamine were identified and spermine and spermidine were detected. As carbonyl compounds, acetaldehyde, acetone, 2-butanone, 2-heptanone, methanol, ethanol, and butanol were identified. Any sulfur compounds could not be detected. It seems likely that smell of fresh egg white is originated from mixing these amines and neutral compounds detected in this and the previous report.

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