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1.
G protein-coupled receptor (GPR) 120 is an unsaturated fatty acid receptor, which is associated with various physiological functions. It is reported that the genetic variant of GPR120, p.Arg270His, is detected more in obese people, and this genetic variation functionally relates to obesity in humans. Obesity is a common nutritional disorder also in dogs, but the genetic factors have not ever been identified in dogs. In this study, we investigated the molecular structure of canine GPR120 and searched for candidate genetic variants which may relate to obesity in dogs. Canine GPR120 was highly homologous to those of other species, and seven transmembrane domains and two N-glycosylation sites were conserved. GPR120 mRNA was expressed in lung, jejunum, ileum, colon, hypothalamus, hippocampus, spinal cord, bone marrow, dermis and white adipose tissues in dogs, as those in mice and humans. Genetic variants of GPR120 were explored in client-owned 141 dogs, resulting in that 5 synonymous and 4 non-synonymous variants were found. The variant c.595C>A (p.Pro199Thr) was found in 40 dogs, and the gene frequency was significantly higher in dogs with higher body condition scores, i.e. 0.320 in BCS4–5 dogs, 0.175 in BCS3 dogs and 0.000 in BCS2 dogs. We conclude that c.595C>A (p.Pro199Thr) is a candidate variant relating to obesity, which may be helpful for nutritional management of dogs.  相似文献   
2.
Estrus induction is an important step in embryo production. It has been difficult to induce estrus in miniature pigs by intramascular (i.m.) injection of prostaglandin F2alpha (PGF2(2alpha)) in the early luteal stage of the estrous cycle. In the present study, we injected two different doses of PGF2(2alpha) i.m. and into the submucosa of the vaginal vestibule (i.ves.) of miniature pigs, and examined the effect of these treatments on estrus induction. Fifteen miniature pigs were divided into five experimental groups (control, saline injected i.m.; PGF2alpha treated, 1.0 or 1.5 mg of PGF2alpha injected twice i.m. or i.ves.), and the estrus length and concentrations of 17beta-estradiol (E2) and progesterone (P) in the blood were examined. Estrus length was significantly shortened by a large amount of PGF2alpha injected i.ves. In addition, the concentration of P in the blood significantly decreased after two injections of PGF2alpha (i.m. or i.ves.). These results suggest that in miniature pigs, administration of at least 3.0 mg of PGF2alpha is required for the induction of luteolysis and injection of PGF2alpha into the vaginal vestibule is a useful method of estrus induction.  相似文献   
3.
An experiment was conducted using 17 male buffalo calves to assess the effects of plane of nutrition on dry matter intake (DMI), daily gain (DG), body size measurement, apparent digestibility and nitrogen (N) balance. To attain 250 kg BW, the calves were allocated into three groups: H, L‐H and L, receiving the concentrate at 1.50% of BW, 0.75% of BW until 190 kg BW and 1.50% thereafter and 0.75% of BW, respectively. The animals had ad libitum access to urea‐treated rice straw (UTRS). The DMI of UTRS through the experiment was higher in L and L‐H than H, showing 3.52, 2.90 and 2.62 kg/day, respectively (P < 0.01), but the total DMI did not differ among the treatment groups. The DG throughout the experiment was high in the order of H, L‐H and L, showing 0.72, 0.57 and 0.45 kg, respectively (P < 0.01). The digestibility of DM, organic matter, crude protein, neutral and acid detergent fiber and N retention were higher in H than in L (P < 0.05). The findings of this study thus revealed the greater DG has an advantage of shortening the growing period around 3 months, and consequently increasing benefit in fattening of buffalo calves in Nepal.  相似文献   
4.
The meat quality of farmed yellowtail Seriola quinqueradiata fed on extruded pellets (EP) containing 0.5% (v/v) red pepper (experimental group) was compared with yellowtail of the same age fed on EP (control group). In 1-year-old yellowtail, the crude lipid content of the dorsal muscle of the experimental group tended to be lower than that of the control group. In contrast, there was no difference in the lipid content of the dorsal muscle between the control group and the experimental group in 2-year-old yellowtail. The muscle texture of the experimental group was significantly firmer than that of the control group, with the effect of red pepper unrelated to fish age and lipid content. Color change of red muscle of the experimental group was significantly lower than that of the control group, and the content of thiobarbituric acid-reactive substances in the red muscle was significantly lower in the experimental group than in the control group. These results are the first to demonstrate that the inclusion of red pepper in the diet is able to reduce the loss of muscle texture firmness and to slow down color change in red muscle of yellowtail.  相似文献   
5.
In this study, the effect of a vacuum impregnation (VI) process with pulsed electric field (PEF) pretreatment on fortification of whole potato with ferric pyrophosphate was investigated. The VI process and PEF pretreatment were optimized with respect to physicochemical attributes of PEF-VI-processed samples using response surface methodology (RSM). The results indicated that the iron content of VI-processed and PEF-VI-processed potatoes was increased about 126 and 457%, respectively, compared to unprocessed potatoes. A more intensive PEF pretreatment led to a higher cell disintegration, decrease in colour and textural parameters and also increase in components leakage from treated potato. Our study suggests that whole 180-g potatoes should be pretreated at 394 V/cm with 36 pulses and then treated at 3.5 kPa for 37 min in vacuum stage and 39 min restoration time in atmospheric stage to achieve the highest iron fortification and the lowest physicochemical changes during PEF-VI processing.  相似文献   
6.
To identify differences in root plasticity patterns of two upland New Rice for Africa (NERICA) varieties, NERICA 1 and 4, in response to drought under conditions with contrasting soil profile characteristics, soil moisture gradients were imposed using a sloping bed system with depths ranging 30–65 cm and a line-source sprinkler system with a uniformly shallow soil layer of 20 cm depth. Varietal differences in shoot and root growths were identified only under moderate drought conditions, 11–18% v/v soil moisture content. Further, under moderate drought soil conditions where roots could penetrate into the deep soil layer, deep root development was greater in NERICA 4 than in NERICA 1, which contributed to maintaining dry matter production. However, under soil conditions with underground impediment to deep root development, higher shoot dry weight was noted for NERICA 1 than for NERICA 4 at 11–18% v/v soil moisture content, which was attributed to increased lateral root development in the shallow soil layer in NERICA 1. Enhanced lateral root development in the 0–20-cm soil layer was identified in NERICA 1 even under soil conditions without an impediment to deep root development; however, this did not contribute to maintaining dry matter production in upland rice. Thus, we show different root developmental traits associated with drought avoidance in the two NERICA varieties, and that desirable root traits for upland rice cultivation vary depending on the target soil environment, such as the distribution of soil moisture and root penetration resistance.  相似文献   
7.
We evaluated the acute toxicity of the antifouling biocide Sea-Nine 211 to the algae Chaetoceros calcitrans, Dunaliella tertiolecta, Tetraselmis tetrathele, and Skeletonema costatum, the crustacea Tigriopus japonicus and Portunus trituberculatus, and the polychaete Perinereis nuntia. The algae, and especially the diatoms C. calcitrans and S. costatum, were sensitive to Sea-Nine 211 toxicity, with the average acute toxicity values being 0.32, 3.9, 1.6, 0.22, 1.6, 12, and 27 μg/l for C. calcitrans, D. tertiolecta, T. tetrathele, S. costatum, T. japonicus, P. trituberculatus, and P. nuntia, respectively. A sediment toxicity test for Sea-Nine 211 using the polychaete P. nuntia revealed demonstrated that the 14-day median lethal concentration was 110 μg/kg dry-wt sediment and that growth was the most sensitive indicator. The chronic toxicity values of Sea-Nine 211 for the diatoms C. calcitrans and S. costatum were within the range of reported Sea-Nine 211 concentrations in seawater in coastal Japan, and the toxicity values for P. nuntia were within the reported concentrations in sediment. Based on these results, Sea-Nine 211 may have toxic effects on some sensitive species residing in the coastal areas of Japan, but the ecological risk posed by Sea-Nine 211 would appear to be confined to a limited area of Japanese coastal waters.  相似文献   
8.
A combination of silvicultural species [Prosopis cineraria (L.), Ailanthus excelsa Roxb. and Colophospermum mopane (J. Kirk ex Benth.)] were planted with horticultural species [Ziziphus mauritiana (L.), Cordia myxa (Forster), and Emblica officinalis (Gaertn)] and intercropped with wheat (Triticum aestivum). Z. mauritiana +P. cineraria combination produced greater fruit, fodder and fuel wood and was less competitive to wheat crop. Crop yield reduced by 5% to 23% in the agroforestry systems than the yield in sole crop plot. Lowest yield was in C. mopane + C. myxa combination. Fodder yield was 0.53, 0.20 and 0.07 t ha?1 from C. mopane (cursive), P. cineraria and A. excelsa, respectively, whereas utilizable biomass was 2.63 t ha?1 from C. myxa (cursive) + P. cineraria, 2.21 t ha?1 from C. myxa (cursive) + C. mopane and 2.18 t ha?1 from Z. mauritiana + P. cineraria combinations. Soil organic carbon and NH4–N increased (by 7% and 8%, respectively), whereas NO3–N and PO4–P decreased in agroforestry compared to the sole tree plots. Primary root attributes of P. cineraria, A. excelsa and C. mopane were higher in agroforestry and mostly concentrated in the top 0–25 cm of the soil layer. Z. mauritiana + P. cineraria were the best combination with minimum yield reduction and were found to be beneficial in enhancing soil fertility.  相似文献   
9.
O-sec-butylphenyl methylcarbamate (BPMC), an anticholinesterase carbamate, was injected once (100 mg/kg, s.c.) or repeatedly (50 mg/kg/day for 10 days) into mice. Animals were examined for their behavior and for parameters of cholinergic activity in the forebrain. Mice that received only a single injection exhibited reduced ambulation, hypothermia, and impairment of rotarod performance for up to 3 hr after a single injection. BPMC increased levels of acetylcholine (ACh) in the forebrain for up to 6 hr, and decreased acetylcholinesterase (AChE) activity for up to 24 hr. Both high-affinity choline uptake (HACU) and binding of [3H]quinuclidinyl benzilate (QNB) were reduced 20 min after a single injection without any effect on choline acetyltransferase (ChAT) activity. In behavioral tests conducted 10 min prior to the daily injections, rotarod performance and ambulation were slightly impaired for a few days before and after cessation of injection. Repeated treatment decreased HACU and binding of [3H]QNB for 24 hr after the final injection without any changes in levels of ACh content, AChE activity and ChAT activity. BPMC may reversibly impair cholinergic functions through effects not only on AChE activity but also on HACU and binding of [3H]QNB.  相似文献   
10.
Corkwing wrasse, Symphodus melops, is one of the main species used as cleaner fish to combat sea lice infestation in salmon aquaculture; however, there is little knowledge about its biology. Here, we describe the embryonic development of this species and examine the viability of the eggs under three temperature regimes. The experiments were conducted at three water temperature regimes, 12, 15, and 18°C, which resemble common sea water temperatures registered during the spawning season of corkwing wrasse at different latitudes along the Norwegian coast. Corkwing wrasse spawn small spherical eggs of 0.75–0.80 mm in diameter (mean 0.78, CV = 3.6%) with several oil droplets and go through eight developmental stages until hatching. The shortest hatching time was registered after 144 hr at 18°C and after 222 and 372 hr at 15 and 12°C, respectively. These observations provide important baseline biological information to advance the establishment of commercial rearing techniques and sustainable fishing management practices for this heavily exploited species.  相似文献   
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