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1.
To determine the factors affecting agonistic interactions after regrouping, 24 pigs were allocated to six pens that each had a box. Half of the pigs were experienced in using the box. One castrated male and one female pig were transferred from each pen to another pen at random. The number of pigs attacked was particularly large for the pigs that had no experience in using the box and were transferred on the first day ( P <  0.05). The duration of access to the box was markedly longer for the pigs that had experience in using the box and were not transferred on the first day ( P <  0.05). The number and duration of attacks were significantly larger and longer toward unfamiliar individuals than toward familiar ones (both P < 0.01). The number of attacks toward the same sex was significantly larger than toward the opposite sex ( P <  0.01). A negative correlation was found between the number of agonistic interactions on the first day and the range of body weights in the pen mates ( r =  −0.78, P  = 0.07). In conclusion, regrouping with unfamiliar individuals should be avoided, but when unavoidable, the following methods are recommended to reduce agonistic interactions: (1) ensure the intruders are experienced in using a box, (2) move experienced intruders in with residents that have no experience in using a box, (3) mix different sexes, and (4) have wide variations in body weights in a pen.  相似文献   
2.
Lactobacillus rhamnosus GG (LGG) is a well‐established probiotic strain. The beneficial properties of this strain are partially dependent on its prolonged residence in the gastrointestinal tract, and are likely influenced by its adhesion to the intestinal mucosa. The pilin SpaC subunit, located within the Spa pili structure, is the most well studied LGG adhesion factor. However, the binding epitopes of SpaC remain largely unknown. The aim of this study was to evaluate the binding properties of SpaC to the carbohydrate moieties of intestinal glycoconjugates using a recombinant SpaC protein. In a competitive enzyme‐linked immunosorbent assay, SpaC binding was markedly reduced by addition of purified mucin and the mucin oligosaccharide fraction. Histochemical staining revealed that the binding of SpaC was drastically reduced by periodic acid treatment. Moreover, in the surface plasmon resonance‐based Biacore assay, SpaC bound strongly to the carbohydrate moieties containing β‐galactoside at the non‐reducing terminus of glycolipids. We here provide the first demonstration that SpaC binds to the oligosaccharide chains of mucins, and that the carbohydrate moieties containing β‐galactoside at the non‐reducing termini of glycoconjugates play a crucial role in this binding. Our results demonstrate the importance of carbohydrates of SpaC for mucus interactions.  相似文献   
3.
The differential variables for carcass grades were identified from morphological, behavioral and physiological measurements of young steers at a commercial farm. Thirty‐five Japanese Black × Holstein steers aged 6–10 months were randomly assigned to three pens. The steers had free access to ryegrass hay and a restricted amount of concentrate diet for the first 6 months of trial. They were then given oat straw ad libitum and an additional concentrate diet until slaughter. Behavioral observations (15 categories) were carried out once every 2 weeks for 2 h after feeding. Bodyweight was measured, blood sampled (for seven metabolic hormones and five metabolites), ultrasonic scanning conducted and physical measurements taken (10 parts for each animal) in months 1, 3 and 5 (early fattening stage, EFS) and in months 7, 9 and 11 (middle fattening stage, MFS) of the trial. Temperament scores during these procedures, entry order into restraint stalls, social rank and average daily gain were also assessed. A factor analysis and one‐way anova were used to identify clusters of variables which had different factor scores between carcass grades. As for the carcass yields, a cluster of chest girth and depth, bodyweight, withers and hip height, and rump length (P < 0.01), and a cluster of the frequency of scratching the body with facilities (P < 0.05) were identified as differential variables in the EFS. In the MFS, a cluster of concentrations of cortisol and epinephrine, and the frequency of eating straw were identified (P < 0.10). As for the carcass quality grade, a cluster of social rank, triglyceride concentration and the frequencies of stand‐chewing cud and eating hay, and a cluster of the frequency of investigating facilities (both P < 0.10) were identified in the EFS. In the MFS, a cluster of hip height, bodyweight, cannon circumference, chest depth, withers height and chest girth, and a cluster of the frequencies of eating a concentrate diet and stand‐chewing the cud, and social rank (both P < 0.10) were identified. In conclusion, bodyweight, chest girth and depth, withers and hip height were identified as good differential variables for future carcass grades of young steers. Facility enrichment that encourages steers to eat hay in the EFS, and to eat a concentrate diet in and after the MFS would be effective in upgrading carcass grades. High incidence of investigating and scratching the body with facilities and stand‐chewing the cud might lead to lower carcass grades.  相似文献   
4.
Commercial dairy cows milked in a parlor system are packed close together in the holding area before milking. The present study examined the relationships of ‘looking up’ behavior with some other behaviors and the productivity of 1116–1153 cows from five farms. The individual identities of the cows looking up in the holding area were recorded at 5 min intervals during six intermittent afternoon milking sessions. Entrance into the milking parlor and the numbers of steps and kicks by cows while the milking person was attaching the milking cups, were recorded in six milking sessions. Flight responses in the pasture after milking were recorded over four days intermittently. The frequency of ‘looking up’ behavior weakly, but significantly correlated with flight starting distance (r = 0.10, P < 0.05), while the correlation with the number of step‐kicks during milking was not significant. As for productivity, lactation number (r = ?0.18, P < 0.001), milk yield (r = ?0.15, P < 0.001) and fat content (r = ?0.15, P < 0.001) were negatively correlated with the frequency of ‘looking up’ behavior. Age of cows was correlated with the frequency of ‘looking up’ behavior as well as lactation number (r = ?0.21, P < 0.001). Entrance order was positively correlated with the frequency of ‘looking up’ behavior (r = 0.15, P < 0.001). The ‘looking up’ behavior was observed more frequently in cows in their third or less lactation compared with cows which were in their fourth or greater lactation (P < 0.05). The lactation number of cows was correlated with their milk yield (r = 0.36, P < 0.001) and flight starting distance (r = ?0.21, P < 0.001). In conclusion, ‘looking up’ behavior shown by cows in the holding area before milking might be an indicator of low motivation for milking, mainly because of fear of humans, and an aversion to milking caused by insufficient experience in being milked.  相似文献   
5.
Twenty-one synthetic compounds, containing one or more furan rings, were demonstrated to possess anti-juvenile hormone (AJH) activity as evidenced by their induction of premature metamorphosis in the milkweed bug, Oncopeltus fasciatus (Dallas) by contact, topical application or fumigation. The ED50 of the four most active analogs required to induce precocious metamorphosis from 3rd-instar nymphs by residue contact in a Petri dish compared favorably with that of precocene II (6,7-dimethoxy-2,2-dimethyl 2H-chromene) a naturally occurring phytochemical AJH. Precocious metamorphosis was fully reversible by co-treatment with juvenile hormone (JH III) or JH analogs, demonstrating that the observed AJH activity resulted from an induced deficiency of juvenile hormone.  相似文献   
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8.
Present electron microscopical and immunocytochemistrical studies elucidated some morphological relationship between intercalated duct (ICD) and pancreatic islet cells in the chicken in streptozotocin (STZ) and/or camostat mesilate (CM) administrations. Twenty-one chickens were set into four experimental groups: (1) control group, (2) STZ administration group, (3) CM administration group, and (4) STZ + CM administration group. Cytoplasms of ICD cells stained more strongly with eosin in STZ administration group than other groups, and electron-dense materials and intercalated processes between ICD and islet cells were also increasing in time dependence in STZ administration. Number of pancreatic islet in STZ + CM co-administration was about 3.1 times larger than other groups. Many small sized cells were detected at surrounding area of ICD and they incorporated 5-bromo-2'-deoxyuridine better than other experimental groups. Present morphological data suggested that ICD cells might support some tolerances of pancreatic endocrine cells against toxic substances and also involve in regeneration of new pancreatic islet cells in STZ + CM co-administration.  相似文献   
9.
We determined differences in the behavior of the progeny of two major sire lines of Japanese Black cattle by recording the behavior of 35 and 70 half-sib steers of sires from fast (FG) and slow (SG) growing lines, respectively. Two sire lines of steers were mixed and allocated to nine pens with 11–12 animals per pen. The proportion of steers lying was significantly (P < 0.001) higher in the SG line (43.4 ± 5.7% compared to 40.3 ± 6.0%). The proportion of time spent eating concentrate feed (FG: 12.1 ± 2.3%; SG: 11.4 ± 2.1%), drinking (FG: 0.8 ± 1.1%; SG: 0.4 ± 0.6%), licking the feed trough (FG: 0.4 ± 0.6%; SG: 0.2 ± 0.4%) and performing tongue-playing (FG: 3.1 ± 4.6%; SG: 1.0 ± 1.9%) was significantly higher in FG, whereas the proportion of time spent resting (FG: 41.5 ± 12.8%; SG: 43.7 ± 10.9%) and performing self-licking (FG: 1.7 ± 1.4%; SG: 2.1 ± 1.3%) was higher in SG (all P < 0.05). These results show progeny of the FG sire engaged in more active behaviors compared to the progeny of the SG sire line.  相似文献   
10.
The relationship between the sugar content and absorption spectra was investigated using a near-infrared (NIR) spectrometer to visualize the sugar content of a melon. The absorbance at 676 nm, which is close to the absorption band of chlorophyll, exhibited a strong inverse correlation with the sugar content. A high-resolution cooled charged couple device imaging camera fitted with a band-pass filter of 676 nm was used to capture the spectral absorption image. The calibration method used for converting the absorbance values on the image into the degrees Brix sugar content was developed in accordance with NIR spectroscopy techniques. When this method was applied to each pixel of the absorption image, a color distribution map of the sugar content was constructed.  相似文献   
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