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101.
The recurrence of reduced milk flow is a common sequela after placement of teat inserts in the streak canal as a treatment for teat injury. We evaluated the effects of three types of commercial teat inserts on wound healing. Thirty-two normal streak canals of eight cows were incised longitudinally using a teat knife. Then, a wax-bougie, silicone self-retaining cannula, and catgut teat dilator were placed in each cow for 7 days. No insert was placed on the remaining teat as a control. Histopathological examination revealed that granulation polyps with squamous metaplasia developed in the area around the rosette of Furstenberg in most teats in which silicone cannulas and catgut teat dilators were placed, whereas the controls and the teats with wax-bougies healed with less tissue reaction. This study suggests that the placement of irritating inserts, such as a silicone cannula and catgut teat dilator, interfere with wound healing.  相似文献   
102.
Recent in vitro evidence suggests that the phytol‐derived fatty acids, phytanic acid (PA) and pristanic acid (PrA), are components of animal products with the potential to cause both beneficial and harmful effects on human health. In this study, we investigated the in vivo tissue accumulation of PA and PrA and the changes in tissue lipid profiles, using mice fed a phytol‐containing diet. After 4 weeks of treatment with a diet containing 1.0% phytol, plasma, adipose tissue, liver, and brain were collected and their lipid profiles were biochemically and gas‐chromatographically determined. Dietary phytol caused PA and PrA accumulation in the adipose tissue and liver but not in the brain, and reduced plasma and liver triacylglycerol levels. Phytol intake also decreased the fatty acid concentrations in the adipose tissue, especially polyunsaturated fatty acids such as linoleic acid, but increased the concentrations of these fatty acids in the liver. However, dietary phytol had a low impact on the brain lipid profile. This study suggests that dietary phytol intake caused accumulation of PA and PrA and modified lipid profiles in the adipose tissue and liver, but that the brain is an insusceptible tissue to dietary phytol‐induced changes.  相似文献   
103.
Mycoplasma pneumonia of swine (MPS) is caused by Mycoplasma hyopneumoniae (M.hp) and is a common chronic respiratory disease of pigs. Recently, a genetically selected variant of the Landrace pig (Miyagino L2) has a lower incidence of pulmonary MPS lesions. We investigated the pathological and immunological characteristics of MPS resistance in these pigs (n = 24) by comparing with the normal landrace pig (control: n = 24). The pathological MPS lung lesion score in MPS‐selected landrace pigs was significantly lower than in the control. The gene expression of interleukin (IL)‐12p40, which acts as a chemoattractant and a component of the bioactive cytokines IL‐12 and IL‐23, was significantly higher at the hilar lymph nodes, lung, and spleen in MPS‐selected landrace pigs than in control landrace pigs, and these were negatively correlated with the macroscopic MPS lung lesion score. In summary, we demonstrate that resistance against MPS in Miyagino L2 pigs is associated with IL‐12p40 up‐regulation, in comparison with normal landrace pigs without the MPS vaccine. In addition, a comparative study of macroscopic MPS lung lesions and IL‐12p40 gene expression in lung and hilar lymph nodes may lead to beneficial selection traits for the genetic selection for MPS resistance in pigs.  相似文献   
104.
105.
ABSTRACT:   The concentration of aquatic bacteria is basic information required to evaluate the status of environments and to assess bacterial contribution to material cycles. However, the standard direct counting method using epifluorescence microscopy (EFM) is tedious and there is variation in the counts among workers. Here an automatic counting system that consists of Bioplorer (BP) and image analysis has been applied to marine bacteria. BP is composed of a light-emitting diode (LED) illuminant, an optical unit, a driving stage and a charge-coupled device camera. In combination with fluorescent labeling and simplified membrane filtration, bacteria are enumerated automatically. The reproducibility, sensitivity and accuracy of the system were tested for natural marine bacteria, in comparison with EFM and flow cytometry (FCM). The counts obtained by BP showed good correlation with those obtained by EFM and FCM methods. The counts were significantly higher in inshore and oceanic samples, indicating high sensitivity with low background noise. Considering its reproducibility, objectivity, ease of use and compact size, BP can be used as a routine tool for counting aquatic bacteria in substitution for EFM or FCM.  相似文献   
106.
107.
Two species of codlet (Bregmacerotidae) larvae were collected during nine survey cruises conducted in the south-eastern Brazilian Bight between 23oS and 30oS in 1985-91. Of 4846 codlet larvae collected during nine cruises, 99.2% were identified as Bregmaceros canton and only 0.8% were B. athanticus. The two species were more abundant during winter in the neritic region (60–135 m depth). Vertical distribution of codlet larvae was studied using the BIOMOC net, and vertical profiles of temperature/salinity and chlorophyll a concentration were recorded by CTD and fluorescent sonde. Only 9.0% of larvae were collected in the upper 30 m and 91.0% were found deeper (> 40 m). The depths of highest density of larvae bore a close relationship to the subsurface chlorophyll maximum layer. Some B. canton larvae were found in the upper 30 m layer at night, but no larva was found during the day. Water temperatures where B. canton larvae occurred ranged from 16 to 23oC, but most larvae were found at 18–20oC and in salinities of 35.5–36.5 psu.  相似文献   
108.
ABSTRACT: To reveal the ontogeny of pancreatic exocrine function in the early larval stage of eel, cDNAs encoding major pancreatic enzymes, trypsinogen, amylase and lipase were identified from the Japanese eel Anguilla japonica and their expression pattern in larvae was analyzed. The cloned eel trypsinogen precursor consisted of 224 amino acids and showed 82.2% identity to trypsinogen-2 of winter flounder Pleuronectes americanus . The eel amylase precursor consisted of 512 amino acids and showed 77% identity to winter flounder amylase. Eel pancreatic lipase was composed of 470 amino acids and had 58.3% of identity to human pancreatic lipase. In the eel larvae, mRNA expression of trypsinogen and amylase was first detected at 6 days post-hatching (d.p.h.), and the expression level increased between 7 and 8 d.p.h. In contrast, mRNA expression of lipase was first detected at 8 d.p.h. Eel larvae start to feed actively at 8 d.p.h. Thus, it was indicated that eel pancreas starts to synthesize digestive enzymes at 6 d.p.h. and acquires full function by the onset of exogenous feeding at 8 d.p.h.  相似文献   
109.
ABSTRACT:   The net-shape and loading analysis system (NaLA) was developed to determine fishing net configuration and load in a previous study. The system has since been applied to general gill nets and aquaculture nets, and its validity has been proven through model experiments in tanks. In this study, the system was applied to estimate the dynamic behavior of a bottom gill net for walleye pollock, to test the system's applicability of the system to gear operations in the field. To obtain in situ data, four bottom gill net operations were performed in February 2004 off the coast of Sawara, Hokkaido, Japan. During operations, vertical displacements of the bottom gill net's float and sinker lines were measured as representative values of gear behavior, and ocean current direction, and speed at the gear position were observed simultaneously. Then, bottom gill net behavior was simulated using NaLA, incorporating observed environmental conditions and gear specifications. The resulting calculated behavior was compared to measured behavior in terms of the relationship between net height and environmental or setting conditions. Agreement between the calculated and measured net behavior was found. Thus, it is believe that our NaLA calculation model has the potential to simulate the dynamic behavior of bottom gill nets in situ .  相似文献   
110.
利用Granier树干液流测定系统,长期监测黄土高原半干旱区延安市南郊天然辽东栎林优势木的树干液流,并同步监测环境因子(空气温度、湿度、太阳辐射、土壤含水量)。分析3株优势木边材液流在生长季内各月份的日变化特征以及液流通量密度与环境因子的关系。结果显示:辽东栎液流日变化总体上与太阳辐射和空气水气压亏缺呈相同趋势,但液流峰值出现时间较早,通常为10:00左右。随着生长季内物候变化,液流通量密度总体表现为前期(4—6月)较低、中后期(7—9月)较高、末期(10月)迅速下降的变化趋势。采用指数饱和曲线函数对液流通量密度和空气水气压亏缺进行拟合,有效地反映了各月份液流通量密度对空气水气压亏缺的响应特征。各月份的曲线特征和拟合参数的差异表明,蒸腾耗水过程也受到土壤水分状况等其他因素的影响。  相似文献   
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