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1.
To ascertain whether growth rate modifies the oxidative capacity of fish white muscle, we examined the effects of individual
growth rate on the activities of four mitochondrial enzymes in white muscle of the fast growing Atlantic cod,Gadus morhua. Growth rates were individually monitored in cod held at three acclimation temperatures during experiments repeated in four
seasons. The size dependence of citrate synthase (CS), cytochrome C oxidase (CCO) and β-hydroxyacyl CoA dehydrogenase (HOAD)
activities was established using wild cod ranging from 115 to 17,350 g. Given their negative allometry, CS and CCO activities
in the experimental cod were corrected to those expected for a 1.2 kg animal. HOAD activities did not change with size. The
specific activities of CCO and CS were positively correlated with growth rate. However, for both enzymes, season explained
more of the variability than growth rate or temperature. Season was the only factor to significantly affect the activity of
HOAD, while temperature and season interacted to determine glutamate dehydrogenase activity. CS activity was positively correlated
with the initial condition of the cod, which differed among the seasons. The other enzymes did not show this relationship.
The independent changes of these enzymes suggest that mitochondria undergo qualitative modifications with changes in growth
rate, season and size. Although growth rate and the activities of CCO and CS are positively correlated, the activity of the
mitochondrial enzymes is more affected by size, physical condition and season. 相似文献
2.
H Lapierre G Pelletier D Petitclerc P Dubreuil J Morisset P Gaudreau Y Couture P Brazeau 《Journal of animal science》1991,69(2):587-598
Sixty male dairy grain-fed calves, raised from 70 to 223 kg BW in individual crates, were used in a 2 X 2 factorial arrangement to determine the effect of administration of human growth hormone-releasing factor (1-29)NH2 (GRF) and(or) thyrotropin-releasing factor (TRF). Calves received twice-daily s.c. injections of .9% NaCl (control), GRF (5 micrograms/kg BW), TRF (1 micrograms/kg BW) or GRF (5 micrograms/kg BW) plus TRF (1 micrograms/kg GTRF). Average daily gain and days on feed were not affected by treatments, but TRF treatment increased (P less than .05) total intake of dry matter (DM) and feed conversion ratio: 3.00, 3.02, 3.08, and 3.22 kg DM/kg weight gain for control, GRF, TRF, and GTRF, respectively. During two 7-d periods, after 66 and 75 d of treatment, feces and urine were collected from 40 calves (5 per treatment per period). Treatment with GRF increased (P less than .05) digestibility of DM, nitrogen (N), and energy and tended (P less than .20) to increase N retention. At slaughter, withers height was increased (P = .05) by GRF and carcass length was increased (P less than .05) by TRF. Pituitary and liver weights were increased (P less than .05) by TRF. The combination of GRF and TRF slightly increased (P less than .10) protein content and decreased (P less than .05) fat content of the 9-10-11th rib section. After d 1, GRF treatment chronically increased (P less than .05) insulin concentrations and also increased (P less than .10) IGF-I concentrations on d 29 and 57. In summary, chronic treatment with GRF and(or) TRF did not improve growth or efficiency, although GRF increased digestibility of DM, N, and energy and the GRF plus TRF combination resulted in slightly leaner carcasses. 相似文献
3.
Doucet D Otter DE Gauthier SF Foegeding EA 《Journal of agricultural and food chemistry》2003,51(21):6300-6308
Extensive hydrolysis of whey protein isolate by Alcalase was shown to induce gelation mainly via hydrophobic interactions. The aim of this work was to characterize the peptides released in order to better understand this phenomenon. The apparent molecular mass distribution indicated that aggregates were formed by small molecular mass peptides (<2000 Da). One hundred and thirty peptides with various lengths were identified by reversed-phase high-performance liquid chromatography coupled with electrospray ionization mass spectrometry. Alcalase was observed to have a high specificity for aromatic (Phe, Trp, and Tyr), acidic (Glu), sulfur-containing (Met), aliphatic (Leu and Ala), hydroxyl (Ser), and basic (Lys) residues. Most peptides had an average hydrophobicity of 1-1.5 kcal/residue and a net charge of 0 at the pH at which gelation occurred (6.0). Therefore, an intermolecular attractive force such as hydrophobic interaction suggests the formation of aggregates that further leads to the formation of a gel. 相似文献
4.
Dimitris Zianis Gavriil Xanthopoulos Kostas Kalabokidis George Kazakis Dany Ghosn Olga Roussou 《European Journal of Forest Research》2011,130(2):145-160
Empirical allometric equations relating biomass of aboveground components to dendrometric variables for Pinus brutia Ten. trees are derived in this paper. They are based on data collected from Lesvos (North Aegean Sea) and Crete (South Aegean Sea) Islands. Comparisons to published equations for the same species growing in northwestern and southeastern Turkey, for Pinus nigra A. growing in Turkey and Pinus halepensis Mill. found in Western Aegean (island of Evia), are also presented. The biomass of branches from destructively sampled trees (twelve in Crete and six in Lesvos) was divided into four size classes (0?C0.63 cm, 0.64?C2.5 cm, 2.51?C7.61 cm, and 7.62?C22.8 cm). Tree crown biomass was calculated as the sum of the biomass in the four classes plus the fraction of stem above crown base. Over bark stem biomass was estimated through bole volume conversion based on wood density. The results showed clearly that, for a given diameter, the Cretan trees had more crown biomass and a higher share of small branches than trees on Lesvos, probably due to differences in environment and stand structure. Comparisons to published diameter versus crown biomass equations reveal a lower crown biomass for Turkish sites of Calabrian pine and Aleppo pine on Evia Island, while only Turkish Black pine seems to be comparable to the Calabrian pine on Crete. The derived allometries can be used for landscape fire behavior modeling, for ecophysiological studies and for the Kyoto protocol requirements of carbon changes in Pinus brutia Ten. forests located in northern and southern Greek sites. 相似文献
5.
A 3-month-old Quarter Horse colt sustained a penetrating injury over the coronary band on the right forelimb resulting in an articular bone sequestrum and septic arthritis of the distal interphalangeal joint. Despite aggressive treatment for septic arthritis, severe osteoarthritis and ongoing sepsis resulted in persistent lameness. Facilitated ankylosis of the distal interphalangeal joint was performed using a combination of open surgical debridement, placement of an autogenous cancellous bone graft and stabilisation within a transfixation cast. Bony ankylosis of the joint was observed radiographically 7 weeks following surgery. Evaluation of the horse 30 months following surgery revealed complete fusion of the middle and distal phalanges, and the distal sesamoid bone. The horse is pasture sound and is used as a breeding stallion. This report describes the surgical approach and case management employed to achieve facilitated ankylosis as a treatment for unresolved septic arthritis of the distal interphalangeal joint. This is the first report of successful facilitated ankylosis of the distal interphalangeal joint in a foal. 相似文献
6.
Ruenphet S Jahangir A Shoham D Takehara K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(4):477-480
A total of 516 slaughter-age ostrich sera were collected in Japan during 2006-2009. Sixty-one of five hundred and sixteen were positive by virus neutralization (VN) test and the titer of most positive samples was low level. Within the 61 positive sera, 35 sera were collected from unvaccinated ostriches. This result implies that these ostriches might have been infected naturally with low-virulent Newcastle disease virus (NDV). Within the 455 negative samples, 125 samples were from vaccinated ostriches. Since ostrich farmers use live attenuated vaccines, it is reasonable that the titer decreased to below detection level by 1 or 1.5 year-old. The above data indicate that NDV has infiltrated into ostrich farms in Japan, and that the efficacy of ostrich ND vaccination is often time-limited. 相似文献
7.
Dany Domínguez-Pérez Carlos Manlio Diaz-Garcia Neivys García-Delgado Yusvel Sierra-Gómez Olga Casta?eda Agostinho Antunes 《Marine drugs》2013,11(8):2873-2881
The phylum Cnidaria is an ancient group of venomous animals, specialized in the production and delivery of toxins. Many species belonging to the class Anthozoa have been studied and their venoms often contain a group of peptides, less than 10 kDa, that act upon ion channels. These peptides and their targets interact with high affinity producing neurotoxic and cardiotoxic effects, and even death, depending on the dose and the administration pathway. Zoanthiniaria is an order of the Subclass Hexacorallia, class Anthozoa, and unlike sea anemone (order Actiniaria), neither its diversity of toxins nor the in vivo effects of the venoms has been exhaustively explored. In this study we assessed some toxicological tests on mice with a low molecular weight fraction obtained by gel filtration in Sephadex G-50 from Zoanthus sociatus crude extract. The gel filtration chromatogram at 280 nm revealed two major peaks, the highest absorbance corresponding to the low molecular weight fraction. The toxicological effects seem to be mostly autonomic and cardiotoxic, causing death in a dose dependent manner with a LD50 of 792 μg/kg. Moreover, at a dose of 600 μg/kg the active fraction accelerated the KCl-induced lethality in mice. 相似文献
8.
Landscape Ecology - Intensification of farming practices is a key factor in population declines of many species, including aerial insectivores. Of these species, Tree Swallow populations have been... 相似文献
9.
Surveillance and characterization of Newcastle disease viruses isolated from northern pintail (Anas acuta) in Japan during 2006-09 总被引：1，自引：0，他引：1
Ruenphet S Jahangir A Shoham D Morikawa K Miyoshi Y Hanawa E Okamura M Nakamura M Takehara K 《Avian diseases》2011,55(2):230-235
A total of 38 Newcastle disease virus (NDV) isolates were obtained from 6060 fecal samples from northern pintail (Anas acuta) ducks collected in the Tohoku district in Japan during 2006-09. One isolate from each sampling location and date was selected for a total of 38 isolates, then 15 of these were characterized for their pathogenicity by mean death time of minimum lethal dose (MDT/MLD) using chicken embryos and by plaque formation on chicken embryo fibroblasts. Furthermore, nine isolates were randomly selected from these 15 isolates, and the fusion protein genes were sequenced to characterize amino acid sequences around the cleavage site. All 15 were confirmed to be nonvirulent by MDT/MLD test, and nine isolates were also confirmed as nonvirulent by the cleavage site of the fusion protein 112G/E-K/R-Q-G/E-R*L117 that was specific for nonvirulent NDVs. The characteristics of nine isolates identified by phylogenic analysis of the fusion protein gene indicated that the isolates belong to genotype I or II. In addition, we also isolated 68 avian influenza viruses and 28 other hemagglutinating viruses. Our data indicate that northern pintails are subclinically infected by, perpetuate, and distribute NDV along with different subtypes of avian influenza viruses and other hemagglutinating viruses during their migrations across vast areas over the Northern Hemisphere to Japan. 相似文献
10.