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111.
ABSTRACT:   The effect of storage temperature (0, 5, 10, and 15°C) and killing procedure (instant, struggled, temperature shocked, and spinal cord destruction killing) on post-mortem changes in the muscle of the horse mackerel caught near Nagasaki, Japan, was investigated. Temporal changes in adenosine triphosphate (ATP), inosine monophosphate (IMP), and lactic acid concentrations were slowest at 10°C storage temperature. The increase in K -values was slower at 10°C and below than at 15°C storage temperature. In addition, 10°C storage temperature was most suitable for maintaining a constant breaking strength value of the muscle. Regarding the effect of killing procedure, temporal changes in ATP, IMP, and lactic acid concentrations were slowest when killed by spinal cord destruction. The increase in K -value and the decrease in breaking strength were also slowest in the spinal cord destruction group. From these results, it was considered that storage at 10°C temperature and spinal cord destruction killing procedure were most effective in delaying post-mortem change in the horse mackerel.  相似文献   
112.
The utilization of copra meal as a feed ingredient is limited because it contains a high level of mannan. However, recent findings indicate that the effect of copra meal on growth performance in broiler chickens can be improved by the supplementation of mannanase in the diet. In the present study, we examined the effect of mannanase‐hydrolyzed copra meal (MCM) on growth performance and muscle protein metabolism in growing broiler chickens (Gallus gallus domesticus). Forty 8‐day‐old male broiler chicks were assigned to two groups (four birds in each pen, five replicates) and fed either a commercial diet (as a control diet) or a diet containing MCM at 0.2% until 22 days of age. Dietary MCM significantly increased the weights of body, breast muscle, and thighs in chickens, whereas the weights of abdominal adipose tissue and liver were not affected. Cumulative feed intake was significantly increased by MCM. Dietary MCM significantly decreased plasma 3‐methylhistidine level. The messenger RNA and protein levels of muscle protein metabolism‐related factors were not altered by MCM. These findings suggest that the growth‐promoting effect of MCM is related to the suppression of muscle proteolysis in growing broiler chickens.  相似文献   
113.
Both the mean concentration and the pulse pattern of growth hormone (GH) in the blood are important for the metabolism and body growth of calves. Transportation is reported to decrease blood GH concentrations in prepubertal male calves. However, the effect of transportation on GH pulsatility remains unknown. Because transportation is important in moving these calves from calf‐production farms to markets or fattening farms, we tested whether transportation decreases their GH pulse frequency. Five calves were subjected to transportation by trucking (transport group), while five were left in their shed (non‐transport group). Both groups were subsequently subjected to frequent blood sampling at 15‐min intervals for 5 h. In the transport group, the cortisol concentrations increased in the first hour (P < 0.05) but significantly decreased thereafter (P < 0.05) to lower than those of the non‐transport group. During the 5‐hour study period, the transport group displayed a similar mean GH concentration relative to the non‐transport group, but displayed a delayed first GH pulse, and a lower number of GH pulses than the non‐transport group (P < 0.05). Hence, transportation is suggested to decrease GH pulse frequency under abnormal cortisol states, presumably suppressing metabolism and body growth in prepubertal male calves.  相似文献   
114.
The objective of this study was to evaluate the effect of substituting brown rice grain for corn grain in total mixed ration (TMR) silage containing food by‐products on the milk production, whole‐tract nutrient digestibility and nitrogen balance in dairy cows. Six multiparous Holstein cows were used in a crossover design with two dietary treatments: a diet containing 30.9% steam‐flaked corn (corn TMR) or 30.9% steam‐flaked brown rice (rice TMR) with wet soybean curd residue and wet soy sauce cake. Dietary treatment did not affect the dry matter intake, milk yield and compositions in dairy cows. The dry matter and starch digestibility were higher, and the neutral detergent fiber digestibility was lower for rice TMR than for corn TMR. The urinary nitrogen (N) excretion as a proportion of the N intake was lower for rice TMR than for corn TMR with no dietary effect on N secretion in milk and fecal N excretion. These results indicated that the replacement of corn with brown rice in TMR silage relatively reduced urinary N loss without adverse effects on feed intake and milk production, when food by‐products such as soybean curd residue were included in the TMR silage as dietary crude protein sources.  相似文献   
115.
The Cry proteins produced by Bacillus thuringiensis are considered to be highly specific insecticidal proteins. Judged to be safe for humans and farm animals due to their insect-oriented selective toxicity, the proteins have been utilized as a biological pesticide and introduced into genetically modified plants. However, some critical fundamental characters of the Cry proteins remain unclear, and the direct effects of activated Cry proteins on mammalian cells have not yet been fully confirmed. Therefore, in this study we employed primary cultured bovine hapatocytes as a model system to determine if Cry1Ab, a Cry protein, affects mammalian cells. There were no significant changes in the secretion of albumin or the morphology of the Cry1Ab-treated cells. The LDH release showed a tendency to increase after the administration of Cry1Ab, but not significantly. Taking these results on bovine hepatocytes into consideration, Cry1Ab has little acute toxicity on mammalian cells.  相似文献   
116.
The insecticidal activity of dinotefuran and 23 related compounds against the housefly, Musca domestica (L) was measured by injection with metabolic inhibitors. Dinotefuran was less active than imidacloprid and clothianidin by a factor of 10 in molar concentrations. Their binding activities to the fly-head membrane preparation were measured by using [125I]alpha-bungarotoxin ([125I]alpha-BGTX) and [3H]imidacloprid ([3H]IMI) as radioligands. The activity of some selected compounds measured with [3H]IMI was 10(4)-fold higher than that measured with [125I]alpha-BGTX. With [3H]IMI as a radioligand, dinotefuran was 13-fold less active than imidacloprid. The inhibitory effect of dinotefuran on the binding of [3H]IMI to the membrane preparation was in a competitive manner. Quantitative analysis of the insecticidal activity of the test compounds with the binding activity measured with [3H]IMI showed that the higher the binding activity, the higher was the insecticidal activity.  相似文献   
117.
A survey was done in an attempt to investigate the epidemiological status of Echinococcus multilocularis in red foxes and raccoon dogs in Otaru city from June to September 1999. Sixty-seven red foxes (Vulpes vulpes schrencki) and 13 raccoon dogs (Nyctereutes procyonoides albus) were captured, and postmortem examinations were conducted with them. Thirty-eight red foxes (56.7%) and 3 raccoon dogs (23.1%) were found to be infected with E. multilocularis. The total biomass of E. multilocularis in all infected red foxes and raccoon dogs were 2,817,000 and 1,515 worms, respectively. Nine of the infected red foxes harboring more than 100,000 worms accounted for 90.6% of the total biomass. No significant differences in the prevalence were observed between male and female, and juvenile and adult. However, the worm burden was higher in juvenile than in adult foxes. In one of the infected raccoon dogs, mature worms and eggs of E. multilocularis were found in the intestine and fecal sample, respectively. This result suggested that the raccoon dogs are probably playing a small role in the egg contamination of the environment. The validity of coproantigen ELISA for diagnosis of foxes was confirmed by comparing the results of autopsy, egg examination and coproantigen ELISA using rectal fecal samples.  相似文献   
118.
We investigated the effect of rice grain conservation methods on feed intake, milk production, blood metabolites, and rumen fermentation in dairy cows. Raw rice grain was dried before crushing (DRY), ensiled after crushing (ENS‐A), or ensiled before crushing (ENS‐B). Twelve multiparous Holstein cows were used in a replicated 3 × 3 Latin square design with three dietary treatments comprising ad libitum access to one of three total mixed rations (TMRs; containing DRY, ENS‐A, or ENS‐B at 17% of dietary dry matter) plus a standard allowance of 2.0 kg/day of dairy concentrates. The dietary treatments did not affect the feed intake, milk yield, or milk composition. The selected blood constituents were not influenced by the rice conservation method. The ruminal lactic acid and total volatile fatty acid (VFA) concentrations and the VFA proportion in the cows were not influenced by the rice conservation method. These results demonstrate that the rice grain conservation method has little impact on lactation performance when cows are fed a TMR containing 17% treated rice grain (dry matter basis).  相似文献   
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