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71.
There appears to be strong evidence supporting four major clades of placental mammals: (i) Afrotheria; (ii) Xenarthea; (iii) Euarchontoglires; and (iv) Laurasiathera. This is the first study in which the carbohydrates have been analyzed in the milks of Xenarthea. Our aim was to clarify whether the saccharides of giant anteater milk resemble those of other eutherian species, especially of the Asian elephant, which is one of the Afrotherea. We found that lactose is a dominant saccharide in this milk, as it is in that of most eutherians, and that the milk contains smaller amounts of oligosaccharides, whose structures were determined as Gal(α1‐3)Gal(β1‐4)Glc (isoglobotriose), Neu5Ac(α2‐6)Gal(β1‐4)Glc (6'‐N‐acetylneuraminyllactose), Neu5Gc(α2‐6)Gal(β1‐4)Glc (6'‐N‐glycolylneuraminyllactose), Neu5Ac(α2‐6)Gal(β1‐4)GlcNAc(β1‐3)Gal(β1‐4)Glc (LST c) and Neu5Gc(α2‐6)Gal(β1‐4)GlcNAc(β1‐3)Gal(β1‐4)Glc. This pattern of milk carbohydrates is rather close to that of the milks of other eutherian species. It is notable that the milk contained oligosaccharides with Neu5Gc residues but no oligosaccharides containing α(2‐3) linked Neu5Ac residues such as Neu5Ac(α2‐3)Gal(β1‐4)Glc.  相似文献   
72.
The objectives of this study were to estimate the heritability of mastitis incidence and genetic correlations between the mastitis and the somatic cell score (SCS) statistics, and to compare the practicability between different models. We used test‐day records with the mastitis incidence and SCS collected from Holstein cows calving from 1988 to 2015 in Hokkaido, Japan. As indicators of mastitis, the average SCS (avSCS), the standard deviation of SCS (sdSCS), and the maximum SCS (maxSCS) were calculated using test‐day records up to the first 305 days in milk within a lactation. We compared a four‐trait repeatability animal model (MTRP) with a four‐trait multiple‐lactation animal model (MTML). The heritability for mastitis was equal to or lower than 0.05 in all the models. Genetic correlations between lactations with MTML within the same trait were positive and close to 1. With MTRP, the estimated genetic correlations of the mastitis incidence with avSCS, sdSCS, and maxSCS were 0.66, 0.79, and 0.82, respectively. A joint evaluation with SCS statistics is expected to give an extra reliability for mastitis because of high and positive genetic correlations among the traits.  相似文献   
73.
This study was conducted to evaluate the effects of supplementation of Wakame seaweed stalks on the immunity and intestinal microflora of pigs. Three separate experiments were performed: Relatively young (start at 20–30 kg; Experiments 1 and 2) and fattening period (70 kg; Experiment 3). All pigs (including the control group) were fed the same commercial feed, free from antibiotic additives, but in the feed for the treatment groups, 1% seaweed powder was added. There were no group differences observed in daily weight gain and feed intake in Experiments 1 and 2 between groups; however, daily weight gain was significantly higher in the treatment group compared to the control group in Experiment 3. The percentage of peripheral blood natural killer cells of the treatment group was significantly higher than that of the control group in all experiments. Although addition of seaweed changed the gene expression of cytokine and toll‐like receptors of the small intestinal Peyer's patches slightly, seaweed seems to alter intestinal microflora preferentially, for instance, there was an increase in Lactobacillus and a decrease of Escherichia coli observed. These results suggest that Wakame seaweed can be used as supplement for pig feed to improve the gut health and immunity of pigs.  相似文献   
74.
Using path analyses, we investigated relationships between size at release from hatcheries, the early marine growth of juveniles, and adult return rates for chum salmon from five river stocks of Hokkaido, Japan, in relation to sea surface temperature during ocean residence. Marine growth was estimated using scales collected from 11 760 adults of age 0.3 (1980–2004). The growth and survival of each stock appeared to have a different suite of regulatory processes. Interannual variability in return rates was mainly regulated by size at release in two stocks from the Sea of Okhotsk. A similar relationship was found in one stock from the Sea of Japan, but growth during coastal residency also affected their return rates. In two stocks from the Pacific coast of Hokkaido, variability in return rates was not related to size at release or to the coastal growth of juveniles, but with offshore growth in the Sea of Okhotsk, the nursery area for juveniles after leaving Japanese coastal waters. Whereas coastal growth tended to be negatively correlated with size at release in some stocks, offshore growth was positively associated with the August–November sea surface temperature in all stocks. This study confirmed that mortality of juvenile salmon occurred in two phases, during the coastal residency and the late period of the growing season, but the relative importance of both phases varied by stock and region, which probably regulated year‐class strength of Hokkaido chum salmon.  相似文献   
75.
Cyprinid herpesvirus 2 (CyHV‐2) is the causative agent of herpesviral haematopoietic necrosis (HVHN) in goldfish, Carassius auratus, and Prussian carp, Cauratus gibelio. In this study, we investigated virus persistence in goldfish experimentally infected with CyHV‐2. Virus DNA presence in organs was monitored in survivors reared at a virus permissive temperature and also in survivors treated with a non‐permissive temperature for 4 days, initiated at three different time points post‐infection in order to obtain fish with different virus loads. We detected virus DNA in all organs tested at 51 days post‐infection (dpi) and in the spleen, trunk kidney and gills of survivors at 81 dpi, although the virus load in fish influenced the subsequent number of organs that tested positive for virus DNA. In addition, some organs dissected from four out of five asymptomatic survivors tested positive by PCR following incubation in vitro in a medium for 5 days. Following inoculation with the homogenate of PCR‐positive kidney incubated in vitro, one of the three inoculated fish died, showing that the detected virus by PCR produced infectious particles. This study suggests that CyHV‐2 can establish a persistent infection in some organs, especially the spleen and trunk kidney, and that asymptomatic surviving fish can be a source of infection.  相似文献   
76.
云南稻种冲腿的孕穗期耐冷性QTL分析   总被引:24,自引:6,他引:24  
 利用352 个探针分析了日本品种农林20和云南品种冲腿之间的限制性片段长度多态性(RFLP),从中筛选出157个在农林20和冲腿间显示多态性的探针,其中55个被用于其杂交后代(农林20/冲腿)的70个F3系统的孕穗期耐冷性数量性状位点(QTL)分析。结果初步显示出一些与水稻孕穗期耐冷性有关的QTL,它们主要分布在第1、3、4、5、6、7、8、10和第12染色体上。可能在第3和第7染色体上具有对孕穗期耐冷性作用较大的QTL。  相似文献   
77.
Fucoxanthin is a marine carotenoid found in edible brown seaweeds. We previously reported that dietary fucoxanthin attenuates the weight gain of white adipose tissue (WAT) of diabetic/obese KK- A(y) mice. In this study, to evaluate the antiobesity and antidiabetic effects of fucoxanthin and fish oil, we investigated the effect on the WAT weight, blood glucose, and insulin levels of KK- A(y) mice. Furthermore, the expression level of uncoupling protein 1 (UCP1) and adipokine mRNA in WAT were measured. After 4 weeks of feeding, 0.2% fucoxanthin in the diet markedly attenuated the gain of WAT weight in KK- A(y) mice with increasing UCP1 expression compared with the control mice. The WAT weight of the mice fed 0.1% fucoxanthin and 6.9% fish oil was also significantly lower than that of the mice fed fucoxanthin alone. In addition, 0.2% fucoxanthin markedly decreased the blood glucose and plasma insulin concentrations in KK- A(y) mice. The mice fed with the combination diet of 0.1% fucoxanthin and fish oil also showed improvements similar to that of 0.2% fucoxanthin. Leptin and tumor necrosis factor (TNFalpha) mRNA expression in WAT were significantly down-regulated by 0.2% fucoxanthin. These results suggest that dietary fucoxanthin decreases the blood glucose and plasma insulin concentration of KK- A(y) along with down-regulating TNFalpha mRNA. In addition, the combination of fucoxanthin and fish oil is more effective for attenuating the weight gain of WAT than feeding with fucoxanthin alone.  相似文献   
78.
The present study was designed to explore the inhibitory mechanism by nitric oxide (NO) of the tachykininergic neuro-muscular transmissions in the hamster ileum. In the presence of guanethidine (1 μM), atropine (0.5 μM), nifedipine (0.1 μM) and apamin (100 nM), electrical field stimuli (EFS; 0.5 ms duration, 15 V) evoked non-adrenergic, non-cholinergic excitatory junction potentials (EJPs) in circular smooth muscle cells. The EJPs were markedly inhibited by the tachykinin NK1 receptor antagonists [D-Pro(4), D-Trp(7,9)]-SP(4-11) (3 μM). Both the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 200 μM) and the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ, 10 μM), did not affect on the resting membrane potentials, but enhanced the tachykininergic EJPs. In the presence of L-NAME (200 μM), exogenously applied NO (10 μM) and the membrane permeable analogue of guanosine 3',5'-cyclic monophosphate (cGMP), 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP, 3 mM), significantly inhibited the tachykininergic EJPs. Application of EFS (0.5 msec duration, 15 V) with trains of 20 pulses at 20 Hz increased amount of released substance P (SP). The release of SP was further increased by the treatment of L-NAME or ODQ, but markedly reduced by exogenously applied NO and 8-Br-cGMP. These results suggest that the endogenous NO may inhibit the tachykininergic neuro-muscular transmissions by the decrease of SP release from the tachykininergic neurons, possibly through a guanylate cyclase-cGMP-dependent mechanism in the hamster ileum.  相似文献   
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