It is important to clarify the influence of essential fatty acids on the incorporation of other acids in cumulative essential fatty acids of egg yolk lipids. As the first step, laying hens were fed mainly a basal diet composed of corn starch and soybean meal and partially diets containing safflower oil linseed oil, or tallow fat, and the fatty acid distribution in egg yolk triglycerides and triglyceride compositions of egg yolk lipids were compared. As the result, the following conclusions were drawn. 1) Linoleic acid of dietary mixtures was preferentially esterified at the 2-position in triglyceride, whereas linolenic acid was esterified at the 1, 3-position rather than the 2-position in triglyceride. 2) Polyunsaturated fatty acids were esterified at the 2-position, and saturated fatty acid predominantly liked at the 1, 3-position in triglycerides of egg yolk lipids. 3) As compared with linoleic acid, linolenic acid showed only a very small incorporation into egg yolk lipids. The position isomerization of linolenic acid in linseed oil was presumed to be an important factor. Feeding of the basal diet and the diet supplemented with tallow showed the same tendency of affinity in the fatty acid distribution as in the triglyceride compositions of egg yolk lipids. 5) The triglyceride composition of egg yolk lipids varied considerably with the fatty acid composition of the diet. 6) The phospholipid fraction of the egg yolk lipid showed a higher distribution value of linoleic acid and little influence of linolenic acid and oleic acid.

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There is a considerable evidence to show that, with diets consisting mainly of roughage, voluntary intake is chiefly regulated by the physical distention or the rate of passage of digesta in the ruminant. This trial was conducted to investigate whether the voluntary intake of rice straw, which was remarkably lower than those of other roughages, was controlled by the similar mechanism or not. Rice straw of mature stage (RMS) was prepared for the control. Rice straw of ear emergence stage (RSEE) and orchard grass hay (OGH) were prepared for the treatment. These were fed ad libitum. As a basal diet, wheat bran was fed 400g a day, twice daily. 1) Total dry matter intake (g/W kg^0.75) was 48 and 69% higher for RSEE and OGH, respectively, than that of RMS. Gross energy intake (kcal/W kg^0.75) was 46 and 123% higher for RSEE and OGH, respectively, than that of RMS. 2) Voluntary intake of only roughage of RSEE and OGH was 82 and 121% higher, respectively, than that of RSEE. 3) Digestibility of total dry matter containing wheat bran was 15% higher for OGH than those of other two treatments. Digestibility of both crude fiber and cellulose was the highest in the case of OGH, the second and the lowest in the case of RSEE and RMS, respectively. There was about 10% variation among three treatments. 4) Digested amount of dry matter was 49 and 142% higher for RSEE and OGH, respectively, than that of RMS. Digested amount of energy presented the same tendency as above mentioned. 5) Reticulo-rumen retention time was 38.0 and 33.5 hr. for RSEE and OGH, respectively. Whereas, it was 54.8 hr. for RMS. 6) Estimated total alimentary tract fill was 66.3 and 67.3g/W kg^0.75 for RSEE and OGH, respectively, but for RMS, it was 50.7g/W kg^0.75 and was the smallest of all. 7) When mature stage rice straw was fed, the rate of passage from the reticulo-rumen of digesta was the slowest and total tract fill was the smallest of all. From these results, it is suggested that physical factors alone are not solely responsible for limiting the intake of rice straw, and that other factors may play a part in regulating the rice straw intake.

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The purpose of this experiment was to show the causes of lower voluntary intake of rice straw from the reticulo-rumen retention time of rice straw and the estimated total alimentary tract fill of all diets under the condition which could increase the voluntary intake of rice straw in wethers. A basal diet and feeding condition of this experiment were about same as the previous report, though three sheep were used including the two used in the previous experiment. The reticulo-rumen retention time and estimated total alimentary tract fill of rice straw crushed with husk machine (crushing) and soaked in 10 per cent sugar solution (soaking) were compared with rice straw (control). The results were as follows. 1) Daily dry matter intake of rice straw in each case of crushing and soaking was 128 and 118 per cent, respectively, of control, and the total dry matter intake per metabolic body size was 116 (crushing) and 111 (soaking) per cent. 2) The significant differences (P<0.05) of digestibility of each component in the total diets recognized among the treatments were as follows: crude fiber: crushing>the others, cellulose: crushing>control, nitrogen free extract: soaking>the others, dry matter and digestible energy: soaking>control. 3) The differences among the treatment in respect to the digested amount of each component in the diet were smaller than in the case of digestibility because of multiplication of intake and digestibility. The digested amount of nitrogen free extract, digestible energy, and dry matter of soaking were still significantly larger than in the other cases. However, the difference of digested amount of crude fiber was insignificant. 4) The reticulo-rumen retention time of rice straw was about the same in the control and the crushing, but in the case of soaking it was a little longer than in the other cases. The differences of reticulo-rumen retention time of those treatments increased according to the increase of amount of intake. The average reticulo-rumen retention time of the control, however, was less than in the cases of the crushing and the soaking, 10 and 16 per cent, respectively. 5) The estimated total alimentary tract fill of the control was the lowest with large difference, though the reticulo-retention time differed little between the control and the crushing. Therefore, it was suggested that the repressed intake of rice straw of the control was not caused by the stagnation of rice straw in reticulo-rumen.

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In this study we investigated the fungal distribution in the cattle feeds. Two farms were epizootically selected at Tama district, Tokyo and we collected several kinds of cattle feeds for 4 times (February, June, August and November). Those feeds were beet pulp, brewer's grain, rice straw, soiling crops, formula feeds, barley, wheat bran and soybean meal. Rice straw and soiling crops were especially highly contaminated with Fusarium species, Penicillium species, Mucorales and other fungi. Those feeds showed more than 5 logarithmic value per gram. In the concentrates including formula feeds, barley, beet pulp and soybean meal, Aspergillus species (mainly A. glaucus) and Penicillium species were frequently isolated. Those feeds showed between 4 and 5 logarithmic value per gram. In general, there was no distinctive change of the contamination of fungi except for beet pulp, which showed the high differentiation between June and other three months. In this investigation, we isolated the fungi which might produce some mycotoxins. Those fungi were A. flavus, A. versicolor, P. citrinum, P. cyclopium and P. expansum in the concentrates, Fusarium species in rice straw and soiling crops.

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[in Japanese]

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It has been reported that a temporary increase of the plasma estradiol concentration as well as of the ovarian Δ5-3β-hydroxysteroid dehydrogenase (HSD) activity takes place in hens about 3 weeks before the time when their first eggs are to be laid. In order to examine the cause of this temporary increase, ovarian interstitial cells and connective tissue cells were observed electron-microscopically in the 15- to 20-week-old hens. The most significant results were obtained from the 16- to 17-week-old hens which were expected to be at the age about 3 weeks before laying their first eggs. In these hens, the interstitial cells suddenly lost a large majority of lipid droplets, provided with markedly well-developed smooth-surfaced endoplasmic reticulum and Golgi apparatus as compared with those in either younger or older hens. The cristae of mitochondria were also remarkably developed. In addition, many connective tissue cells located in the theca of small follicles as well as in the surrounding stroma became rounded in profile, containing smoothsurfaced endoplasmic reticulum, lipid droplets and mitochondria with tubular cristae. These structural changes in the rounded connective tissue cells almost resembled those in the interstitial cells, showing a strong Δ5-3β-HSD activity as did the interstitial cells. Also, among these rounded cells, some possessed well-developed rough-surfaced endoplasmic reticulum. On the other hand, cells located in the outer layer of the theca of large follicles still held ultrastructures characteristic of connective tissue cells, remaining unchanged. The morphological results presented here, particularly for rounded connective tissue cells, strongly support the physiological view of the temporary increase of the estradiol concentration as well as of the ovarian HSD activity at the time before the first eggs are laid.

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Blood typing has been recognized at the most useful technique for keeping of the exact registry of domestic animals in the world, and it has been already applied to the identification of individuals and parentage test for registry of racing horses (Thoroughbred and Anglo-Arab). However, in Japan, there has been no report published on the theoretical analysis in adaptation of each equine blood type systems. Therefore, this experiment has been undertaken to estimate gene frequencies of equine blood types, to clarify the usefulness of blood types as marker genes for identification of individuals and parentage test, to compare their theoretical efficacy with solving rates obtained in actual parentage tests, and thus to establish theoretical basis of utilizing efficacy of equine blood types. The results obtained are as follows: 1. Frequencies of D^cpf6 and Q^a in Thoroughbred were 0.4370 and 0.5913, respectively, which were 10-20% higher than in Anglo-Arab. On the other hand, the frequency of P^au₆ Anglo-Arab was 0.1551, which was 10% higher than in Thoroughbred. 2. In respect to gene frequencies of equine serum protein types, Alb^A in Anglo-Arab was 0.3307, which was 10% higher than in Thoroughbred. While, AlbB in Thoroughbred was 0.7786 and it was 10% higher than in Anglo-Arab. 3. Equnine blood type systems which showed more than 50% probability of identification of individuals were D, P, Tf and Alb systems. The probability of distinguishing individuals calculated from all blood type systems was 0.9994. 4. When genotype of sire was not taken into account, average probabilities negating one of two possible sires by D_b, U_a, P_a, U₆ and Pf₆ factors were 0.0819, 0.0817, 0.0726, 0.0697 and 0.0613 in the order of higher probability, respectively, which were similar to the order obtained in actually tested paternity cases. 5. Among 10 blood type systems, Tf system showed the highest value of average probability negating one of two possible sires. The probability of exclusions by all the systems, when genotype of sire was clarified was 0.8313. While, when his genotype was not taken into account, it was 0.7758. The latter value was similar to solving rate (0.7536) actually obtained in paternity cases.

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This study was carried out in order to clarify whether a heterosis effect of locus, controlling the protein polymorphism of Japanese quail, is to be revealed by inbreeding or not. Test of single-gene heterosis in the inbred strain was examined on the acid phosphatase locus (Experiment I) and on the hemoglobin locus (Experiment II), independently. Brother-sister matings using the heterozygote of the acid phosphatase type or of the hemoglobin type were carried out to produce the inbred strains of Japanese quail. The authors ascertained the heterosis effect of each locus in each inbred generation by comparing the observed ratio with the expected one (1: 2: 1) from AB×AB martings. The results are summarized as follows. 1. Viabilities in the Experiment I and the Experiment II were ascertained to be about 80% in the initial generation (generation 0), decling with the advance of the inbreeding coefficient. The inbred strain in the Experiment I became extinct at the fourth generation. The strain in the Experiment II was maintained during the nine generations of inbreeding and it is now utilizing to produce the strain with more intensive inbreeding coefficient. 2. Progenies obtained from brother-sister mating using the heterozygote of the acid phosphatase type(AB×AB)were segregated into the phenotypes AA, AB and BB in the ratio of 1:2:1, in each generation, except the second generation. 3. Brother-sister mating using hetrozygote of the hemoglobin type, AB×AB, was carried throughout the 10 generations (0th-9th). The phenotypes of AA, AB and BB in each generation were segregated in the ratio of 1:2:1, approximately, although C-value (observed/expected number) of the BB phenotype was a little lower than those of the other phenotypes. 4. From the above results on segregation of phenotypes in both loci in each generation, it was recognized that the heterosis effect in these loci was not to be revealed by inbreeding.

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Structure of the rabbit cervix in estrus was examined macroscopically and microscopically, as a part of physiological and morphological studies of the rabbit cervix. Two cervical canals surrounded by mucosa and musculature were separated completely by a thick median septum. Each canal was provided with the external and internal ora. The cervical mucosa was characterized by the formation of longitudinal folds with many complex crypts. The mucous membrane was lined with a single layer of high columnar epithelial cells composed of two cell types, ciliated and non-ciliated secretory cells. The ciliated cells were predominant in the internal os rather than in the mid-cervix and the external os. Macroscopic examination revealed a distinct transtion of the mucosa from uterus to cervix at the internal os, although the transition was histologically gradual. Both inner circular and outer longitudinal muscular layers were well developed in the uterus, and their muscular bundles were arranged uniformly and regularly. At the proximal end of the cervix, the uterine musculature became loose and the muscular bundles became slender, decreased in number, and dispersed to the vaginal wall. The rabbit cervix contained much fibrous connective tissue as compared with the uterine horn.

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Nine sheep were divided into three groups, three sheep in each. Each group was given a ration containing respectively 0.1, 0.6 and 1.2% calcium. The dietary calcium level was adjusted by the addition of calcium carbonate. From the 30th and the 60th day after the beginning of trial, urine, fecal and serum samples were taken for seven days. After a 67-days feeding period, two sheep from each group were sacrificed, and the livers and spleens were examined to determine trace mineral concentrations. The amount of all trace minerals excreted via urine were too little to affect the mineral balances. There was no significant difference in serum mineral concentrations among treatment groups. Fecal excretion of iron and copper significantly increased and retentions of these trace minerals became negative when the highest calcium ration was given. Liver iron and copper concentrations did not consistently alter, but spleen iron and copper showed a decreasing trend as the dietary calcium was increased. It may be possible that iron and copper requirements increase when a high level of calcium carbonate is given to cattle and sheep.

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