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排序方式: 共有375条查询结果,搜索用时 421 毫秒
111.
Rainbow trout Oncorhynchus mykiss and mirror carp Cyprinus carpio were slaughtered by either percussion or asphyxiation. For determination of the physical (texture value) and biochemical
quality attributes [pH, lactic acid, total volatile basic nitrogen (TVB-N), and malondialdehyde (MDA) values] of trout and
carp, the fish were filleted immediately (within 2 h), 12 h after harvest (pre-rigor), 24 and 36 h after harvest (in-rigor),
and finally 48 and 60 h after harvest (post-rigor). For microbiological quality attribute (mesophilic and psychrophilic bacteria
count) analyses, the fish were filleted immediately (within 2 h) after harvest (pre-rigor), 24 h after harvest (in-rigor)
and 48 and 72 h after harvest (post-rigor). By percussion slaughtering followed by pre-rigor filleting, it was possible to
process rainbow trout and mirror carp without inflicting excessive handling stress. Percussion slaughter delayed onset of
rigor and the percussion-slaughtered fish exhibited a long pre-rigor period (≈24 h), giving plenty time for pre-rigor processing.
Percussion slaughtering and pre-rigor filleting of fish was considered to be superior to the traditional asphyxiation slaughtering
with respect to texture, TVB-N and MDA attributes. 相似文献
112.
Shearing male lambs in the cold season improves the carcass yield without affecting fattening performance 总被引:1,自引:0,他引:1
This research was carried out to determine the effects of shearing of different genotypes of male lambs (one from pure Karayaka stock and two from its crossbreed) in winter on bodyweight gain, feed consumtion, feed conversion efficiency, rectal temperature and carcass yield. A total of 21 lambs aged 8 months were allocated randomly to experimental groups according to a 2 × 3 factorial arrangement for shorn and unshorn animals. The lambs were fed grass hay (100 g/lamb/day) and commercial concentrate feed ad libitum during a 54‐day of fattening period. The lambs were shorn in the middle of the experiment (27 days after beginning the trial). The interaction between the shearing treatment × genotype of the studied parameters was found to be insignificant. The shearing process increased the rectal temperature (P < 0.01), hot carcass yield (P < 0.05) and dressing percentage (P < 0.05) and decreased the weight of the edible inner organs (P < 0.01). Some of these parameters were affected by the genotypes. It was concluded that shearing male lambs in the winter can have a beneficial effect on the hot carcass weight and dressing percentage without affecting fattening performance, and the performance of Karayaka lambs and its crossbred male lambs were similar under the conditions of the present study. 相似文献
113.
Mustafa A Rankaduwa W Campbell P 《The Canadian veterinary journal. La revue veterinaire canadienne》2001,42(1):54-56
Parasitic sea lice are serious problems in aquaculture. The true cost of these parasites is unknown. We demonstrate the economic burden imposed by sea lice, so that researchers, aquatic specialists, and policy makers can approximate the economic cost of this problem and work towards developing alternative control methods. 相似文献
114.
Yang G Wu L Jiang B Yang W Qi J Cao K Meng Q Mustafa AK Mu W Zhang S Snyder SH Wang R 《Science (New York, N.Y.)》2008,322(5901):587-590
Studies of nitric oxide over the past two decades have highlighted the fundamental importance of gaseous signaling molecules in biology and medicine. The physiological role of other gases such as carbon monoxide and hydrogen sulfide (H2S) is now receiving increasing attention. Here we show that H2S is physiologically generated by cystathionine gamma-lyase (CSE) and that genetic deletion of this enzyme in mice markedly reduces H2S levels in the serum, heart, aorta, and other tissues. Mutant mice lacking CSE display pronounced hypertension and diminished endothelium-dependent vasorelaxation. CSE is physiologically activated by calcium-calmodulin, which is a mechanism for H2S formation in response to vascular activation. These findings provide direct evidence that H2S is a physiologic vasodilator and regulator of blood pressure. 相似文献
115.
116.
Bouchon M Karabulut H Aktar M Ozalaybey S Schmittbuhl J Bouin MP 《Science (New York, N.Y.)》2011,331(6019):877-880
Laboratory and theoretical studies suggest that earthquakes are preceded by a phase of developing slip instability in which the fault slips slowly before accelerating to dynamic rupture. We report here that one of the best-recorded large earthquakes to date, the 1999 moment magnitude (M(w)) 7.6 Izmit (Turkey) earthquake, was preceded by a seismic signal of long duration that originated from the hypocenter. The signal consisted of a succession of repetitive seismic bursts, accelerating with time, and increased low-frequency seismic noise. These observations show that the earthquake was preceded for 44 minutes by a phase of slow slip occurring at the base of the brittle crust. This slip accelerated slowly initially, and then rapidly accelerated in the 2 minutes preceding the earthquake. 相似文献
117.
Yasin Demiraslan İftar Gürbüz İsmail Demircioğlu Mustafa Orhun Dayan 《Anatomia, histologia, embryologia》2021,50(3):572-578
The aim of the present study is to reveal the anatomical structure of lumbosacral plexus of barn owl. Six barn owls were included in the study. Nerves originating from plexus were dissected individually, and findings of innervation areas of nerves were determined. Lumbosacral plexus of barn owl was observed to be formed by ventral rami of ten synsacral spinal nerves. It was found that while the r. cutaneus femoris lateralis, the n. obturatorius, the n. coxalis cranialis, the r. cutaneus femoris medialis, the n. cutaneus femoris cranialis and the n. femoralis originated from the lumbar plexus, the n. isciofemoralis, the n. cutaneus femoris caudalis, the n. coxalis caudalis and the n. ischiadicus originated from the sacral plexus. Consequently, when the results of the study were compared with information of different avian species, it was observed that differences focused on the formation of the lumbar and sacral plexuses and innervation level of digits. 相似文献
118.
The effects of a single injection of mammalian superactive analogue [d ‐Ser(tBu)6,Pro9‐NEt]‐LHRHa (20 μg/ kg?1) combined with the dopamine antagonist, haloperidol (HAL, 0.5 mg kg?1), for induction of ovulation in the koi carp broodstocks were determined under routine hatchery conditions. The results were compared with classic carp pituitary extract (CPE, double injection) application (water temperature 22 °C). Physiological saline (0.7% NaCl)‐injected fish were used as a control group and no ovulation occurred in this group. The spawning ratio was high in the LHRHa+HAL treatment group and in the CPE treatment group (6/7 and 5/7 respectively). The latency period was 14–16 h in the LHRHa+HAL treatment group and 12–14 h in the CPE treatment group (after the second injection). There was no difference between the two ovulating groups with respect to the spawning index (the weight of eggs as a percentage of female body weight) and fertilization rate of eggs (P>0.05). As a result, ovulation can be induced successfully in koi carp broodstocks with 20 μg kg?1 [d ‐Ser(tBu)6,Pro9‐NEt]‐LHRHa+0.5 mg kg?1 HAL treatment in a single injection without decreasing the egg quality. Application of this combination can be useful for hatchery and broodstock management in koi carp culture. 相似文献
119.
120.
An isolated non-working trout heart, cannulated through the coronary artery and perfused with oxygenated saline with a coronary
pressure head of 3.0 kPa has been used in this study. Effects on the coronar resistance of catecholamines, thromboxanes (TXs)
and prostacyclin (PGI2) were analyzed. The effects of PGI2 and TXs in presence of noradrenaline were also evaluated. Both adrenaline and noradrenaline vasoconstrict the trout coronary
system, noradrenaline being more potent than adrenaline. TXA2 induces 45% vasoconstriction at 10−6M, while TXB2 at the same concentration is a slight vasodilator. PGI2 acts as a weak vasodilator (about 20% decrease in resistance at 10−6M). In presence of 10−7M noradrenaline, 10−8M TXA2 reduces the vasoconstriction induced by the catecholamine alone from 60% to about 15%. Under similar conditions, 10−9M PGI2 potentiates the vasoconstrictive response induced by noradrenaline while a much higher PGI2 concentration (10−6M) completely abolishes the vasoconstriction. The β-receptor antagonist propranolol induces vasoconstriction, and 10−9M PGI2 in presence of propranolol further increases the vasoconstriction. The α-receptor antagonist phentolamine induces vasodilation
and 10−9M PGI2 does not affect coronary resistance induced by phentolamine. These results imply a possible interaction between noradrenaline
and prostanoids (TXs and PGI2) in the vasomotion of trout coronary system. 相似文献