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The purposes of this study were to examine the relationship between male artificial insemination (AI) fertility and sperm acrosomal conditions assessed by new and conventional staining techniques and to identify possible reproductive dysfunctions causing low conception rates in AI using frozen-thawed spermatozoa with poor acrosomal conditions in Japanese Black bulls. We investigated individual differences among bulls in the results concerning (1) acrosomal conditions of frozen-thawed spermatozoa as assessed by not merely peanut agglutinin-lectin staining (a conventional staining technique) but also immunostaining of acrosomal tyrosine-phosphorylated proteins (a new staining technique), (2) routine AI using frozen-thawed spermatozoa as assessed by pregnancy diagnosis, (3) in vivo fertilization of frozen-thawed spermatozoa and early development of fertilized eggs as assessed by superovulation/AI-embryo collection tests and (4) in vitro fertilization of frozen-thawed spermatozoa with oocytes. The percentages of frozen-thawed spermatozoa with normal acrosomal conditions assessed by the abovementioned staining techniques were significantly correlated with the conception rates of routine AI, rates of transferable embryos in superovulation/AI-embryo collection tests and in vitro fertilization rates. These results are consistent with new suggestions that the distribution of acrosomal tyrosine-phosphorylated proteins as well as the acrosomal morphology of frozen-thawed spermatozoa are AI fertility-associated markers that are valid for the prediction of AI results and that low conception rates in AI using frozen-thawed spermatozoa with poor acrosomal conditions result from reproductive dysfunctions in the processes between sperm insemination into females and early embryo development, probably failed fertilization of frozen-thawed spermatozoa with oocytes.  相似文献   
2.
ABSTRACT:   In order to find out the role of sodium bicarbonate (NaHCO3) on the initiation of sperm motility in the Japanese eel Anguilla japonica , interactions were investigated between NaHCO3 and various reagents (K+ channel blocker 4-aminopyridine [4-AP], ammonium chloride [NH4Cl], sodium acetate and calcium chloride [CaCl2]) that could regulate internal factors (intracellular K+, intracellular pH [[pH]i] and intracellular Ca2+) in sperm motility. Contradictory effects of NaHCO3 were observed (i.e. an inhibitory effect when 4-AP was absent and a promoting effect when 4-AP was present). Sodium bicarbonate inhibited the initiation of sperm motility in the Japanese eel. However, NaHCO3 restored the motility of immotile sperm that 4-AP inhibited. The inhibitory effect of NaHCO3 disappeared with the addition of NH4Cl, which raised [pH]i, but the promoting effect was not affected by [pH]i. Although NaHCO3 recovered motility in the presence of 4-AP, this recovery was also observed with the addition of CaCl2 instead of NaHCO3. In the initiation of sperm motility in the Japanese eel, two roles for NaHCO3 are suggested: an inhibitory role relating to the regulation of [pH]i and a promoting role relating to the uptake of another initiation factor, which could be Ca2+.  相似文献   
3.
To observe the effect of different forms of N, we have applied metabolic profiling using gas chromatography mass spectrometry to evaluate the metabolite composition of spinach. The aim of the present study was to find an appropriate indicator of overall metabolic response to N source. The effect of the     ratio on spinach tissue was investigated, comparing two cultivars that differed in their ability to use N. There was wide variation in     absorption without any distinct growth inhibition in either cultivar. Statistical analysis revealed that the metabolites could be broadly divided into two types, correlating either positively or negatively with     uptake in the culture solution. Principal component analysis (PCA) was an effective tool that extracted the indexes of the effect of the ratio of N forms as PCA scores. Close relationships between metabolite profiles and     uptake were observed, indicating that metabolic profiling is able to distinguish the invisible metabolic change in mature leaves of spinach and may provide a new tool for the investigation of quality features or rhizosphere nutritional condition.  相似文献   
4.
The effects of the fattening period on carcass characteristics, fatty acid composition of fat deposits, and muscle free amino acid (FAA) and inosinic acid (IMP) contents were evaluated in Japanese Black steers. Ten castrated, 10-month-old calves derived from the same sire were divided into five to be slaughtered at the age of 30 months after a 20-month fattening period (20-month group) and five to be slaughtered at the age of 34 months after a 24-month fattening period (24-month group). Concerning the fatty acid composition of subcutaneous fat, the percentage of palmitoleic acid was higher ( P  < 0.05) in the 24- than in the 20-month group, but no difference was noted in any other fatty acids. For intermuscular fat, no difference was observed in any fatty acids. The percentages of oleic acid and total monounsaturated fatty acid of intramuscular and perinephric fat were higher ( P  < 0.05) in the 24- than in the 20-month group. Of the FAAs in the longissimus thoracis muscle, the threonine and tyrosine contents were lower ( P  < 0.05) in the 24- than in the 20-month group. The IMP content was higher ( P  < 0.05) in the 24- than in the 20-month group, suggesting an effect of prolongation of the fattening period.  相似文献   
5.
Oogenesis in the common Japanese conger Conger myriaster   总被引:1,自引:0,他引:1  
TOMOKO  UTOH  NORIYUKI  HORIE  AKIHIRO  OKAMURA  YOSHIAKI  YAMADA  SATORU  TANAKA  NAOMI  MIKAWA  ATSUSHI  AKAZAWA  HIDEO P  OKA 《Fisheries Science》2003,69(1):181-188
ABSTRACT:    We investigated the process and characteristics of oogenesis in the common Japanese conger Conger myriaster . Young fish caught in November 1996 were reared for use in this experiment. Fish were sampled monthly from December 1997 to August 1998. Some were injected with human chorionic gonadotropin to stimulate ovarian maturation from May to August 1998. Oocytes from the chromatin nucleolus stage to the secondary yolk globule stage were obtained from non-hormone-treated fish; those of more advanced stages were obtained from hormone-treated ones. We divided oocyte development into eight stages from the chromatin nucleolus stage to the maturation stage. The yolk vesicle stage was not separated because yolk vesicles began to appear just after appearance of yolk globules. Oocyte, oil droplet, yolk globule and nucleus diameters all increased concomitant with oocyte development. Oil droplet and yolk globule diameters increased remarkably at the maturation stage. However, zona radiata thickness peaked at the secondary yolk globule stage, decreasing gradually thereafter. Increased gonadosomatic index was related to oocyte development as found in European and Japanese eels receiving hormone treatment to mature. The present study is the first report describing oogenesis characteristics in congrid eels. It indicates that oogenesis is almost identical to that of other anguillid eels.  相似文献   
6.
The objective of this study was to investigate the relationship between marbling and serum leptin concentrations. First, we compared serum leptin concentrations between Japanese Black cattle and Holstein calves, and found that the mean serum concentration was significantly higher (P < 0.05) in Japanese Black cattle (2.67 ± 0.41 ng/mL, n = 13) than in Holstein calves (1.79 ± 0.43 ng/mL, n = 5). We then examined the effects of roughage intake or vitamin A on the serum leptin concentrations in Japanese Black cattle. Although the leptin concentrations for the high roughage group were significantly higher than those for the low roughage group at 4, 7 and 20 months old, there was no significant difference in the carcass characteristics of the two groups. In addition, although there was a significant difference in the marbling score between the high vitamin A group and low vitamin A group, there was no significant difference in serum leptin concentrations between the groups. These results suggest that although serum leptin concentrations were not significantly correlated to the marbling scores they may be related to the genetic advantage for marbling in Japanese Black cattle.  相似文献   
7.
The effects of crude protein (CP) concentration in feed using soybean meal as its source in the early fattening period on the levels of free amino acids (FAAs) and dipeptides in the blood, and the levels in the M. longissimus thoracis after slaughter were studied in Japanese Black steers. Sixteen steers were divided into four groups and given feed with a CP content of 12, 14, 16, or 18% of dry matter (DM) from 10 to 20 months old, and they were fed with the same level of CP (13.5–13.9% of DM) until slaughter at 30 months of age. There was no significant difference in the weight gain, carcass weight or marbling score between the groups. Concerning the serum FAA and dipeptide contents at 20 months of age, the alanine, tyrosine and tryptophan levels decreased, while the carnosine (Car) level increased, with increases in the CP level in the feed. Although there were no significant differences in the FAA contents of the Longissimus thoracis muscle between the groups, the Car content decreased with increases in the feed protein level.  相似文献   
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9.
NORIYUKI  HORIE  TOMOKO  UTOH  YOSHIAKI  YAMADA  AKIHIRO  OKAMURA  HUAN  ZHANG  NAOMI  MIKAWA  ATSUSHI  AKAZAWA  SATORU  TANAKA  HIDEO P  OKA 《Fisheries Science》2002,68(5):972-983
Development of embryos and larvae in the common Japanese conger Conger myriaster was observed after artificial fertilization. Eggs were obtained from females matured artificially by hormone injections and milt was obtained from males matured naturally. Fertilized eggs were kept in seawater at 12–14°C. The first cleavage occurred at 4 h, epiboly began at 24 h, the embryonic body was formed at 38 h and hatching occurred at 84 h after insemination. Newly hatched larvae were approximately 2.5 mm (total length) and similar to those of Anguilla japonica in terms of external features. The mouth and anus opened on the 7th day after hatching. Pigments began to appear at the tip of the tail on the 10th day. The total length of the larvae reached approximately 8 mm on the 11th day. Eye pigmentation began on the 14th day. One larva lived for 19 days without food.  相似文献   
10.
One of the bovine growth hormone (GH) genetic variants is a substitution of leucine (Leu) to valine (Val) at amino acid position 127 of the protein. The GH genotypes of 14 Japanese black steers used in the present study were Leu/Leu (A, n = 7) and Val/Val (B, n = 7). The steers in each genotype group were divided into two groups based on intended growth rate (high, 1.0 kg/day; low, 0.6 kg/day) during 10–17 months of age. The overall mean concentration of plasma GH was higher (P < 0.05) in the A group than in the B group. The serum concentration of insulin‐like growth factor‐I was higher (P < 0.05) in the B group than in the A group. The carcass weight of the A group was greater (P < 0.01) than that of the B group. However, there was no significant difference in carcass weights between the 1.0 kg/day and 0.6 kg/day groups (P > 0.05). The rib thickness of the 1.0 kg/day group was greater (P < 0.05) than that of the 0.6 kg/day group. The crude fat content of longissimus muscle was greater (P < 0.05) for the 0.6 kg/day group compared with the 1.0 kg/day group.  相似文献   
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