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1.
The Spontaneously Diabetic Torii (SDT) fatty rat, a model for obese type 2 diabetes, shows bone quantitative abnormalities, namely low bone mineral density (BMD). The objective of this study was to evaluate bone morphological changes, in particular identifying the bone qualitative abnormalities, in the SDT fatty rat. Male SDT fatty rats showed increases in total trabecular area and trabecular number and decreases in trabecular thickness in cancellous bones of the proximal tibia, indicating trabecular miniaturization. The SDT fatty rat is useful for investigation of pathophysiological changes in bone quality in diabetic osteoporosis.  相似文献   
2.
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   
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ABSTRACT:   A total of 110 adult individuals from four ommastrephid (family Ommastrephidae) squid species ( Ommastrephes bartramii, Sthenoteuthis oualaniensis, Eucleoteuthis luminosa, and Hyaloteuthis pelagica ) were used to obtain diagnostic DNA markers for species identification. Restriction fragment length polymorphism (RFLP) analysis of a partial segment (855 bp) of the mitochondrial DNA cytochrome oxidase I (COI) gene amplified by polymerase chain reaction (PCR) revealed that the restriction profiles of two endonucleases ( Alu  I and Tsp 509 I) were diagnostic for species identification. The restriction assay partially supplemented with nucleotide sequence analysis successfully assigned 69 damaged and morphologically equivocal ommastrephid paralarvae collected in northern Hawaiian waters, identifying 60 O. bartramii , eight S. oualaniensis , and one E. luminosa . The family Ommastrephidae appears to be monophyletic. Although the phylogenetic relationships among genera were not resolved well due to apparent homoplasy and large genetic divergence between species, COI sequence data without transitions provided support for subfamily level relationships.  相似文献   
5.
The objective of the present study was to assess cattle welfare during transportation. Vehicle inspection and observation of cattle behavior during loading operations were conducted at two major livestock markets (T and M) in Japan. Market T provided young feeder cattle (Wagyu and cross‐bred aged 6.8–9.0 months) mainly for regions farther than 1500 km. Market M provided young cattle (Wagyu aged 6.6–11.2 month) and calves (crossbred and Holstein aged 0.7–1.5 month) for nearby regions within 500 km. Market T had loading platforms 1.0 m high, whereas market M had partial allocation of platforms and forced most transporters to load cattle from the ground. Vehicles were inspected according to the welfare standards for beef cattle of the RSPCA. Number of vehicles inspected was 36 and 31 in markets T and M, respectively. Cattle hesitations (kneeling down, slipping, balking, backing down, turning around, jumping and eliminating) were observed at the loading ramp. Vehicles inspected at the markets complied with most requirements of the welfare standards, but non‐compliance was found in two requirements: in market M, 71.0% of vehicles had the loading ramp at a >20% incline, whereas 17.1% of vehicles did in market T (P < 0.001). Slope of the loading ramp was steeper in market M than in market T (33.9 ± 17.3% vs. 14.9 ± 8.9%, P < 0.001). Market M had higher proportion of vehicles that did not comply with the requirement ‘Both loading ramps and tail boards must be appropriately designed and covered with litter, to prevent animals from falling off or slipping’ compared with market T (83.9% vs. 17.1%, P < 0.001). Higher frequencies were observed in two kinds of hesitating behavior in market M than in market T (both P < 0.01): mean frequencies (times/head) of slipping and balking were 1.3 ± 1.2 and 2.0 ± 1.8 in market M, and 0.2 ± 0.2 and 0.7 ± 0.5 in market T, respectively. Steeper loading ramp was correlated with higher frequencies of kneeling down (r = 0.53), slipping (r = 0.59), balking (r = 0.45) and backing down (r = 0.42) (all P < 0.05).  相似文献   
6.
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   
7.
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   
8.
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   
9.
Macrophages are essential for controlling the majority of infections, and are mediators of natural immunity. During infection, lipopolysaccharide (LPS) stimulates macrophages to produce pro-inflammatory cytokines. Adenosine and ATP released into the extracellular space by immunological stimuli have been shown to regulate various immune functions. More recently, it has been shown adenosine and ATP have a critical role on the physiological negative feedback mechanism for limitation and termination of tissue-specific and systemic inflammatory responses. It was useful and meaningful to gain information about interaction between LPS, which generates the inflammation, and adenosine and ATP, which terminate the inflammation. We evaluate effects of adenosine and ATP on the production of cytokines related to inflammation in canine macrophage cell line DH82 cells. Adenosine and ATP respectively increased the production of IL-10 without affecting the production of IL-6, TNF-α and IL-12 in DH82 cells. In addition, adenosine and ATP prevented the production of LPS-induced IL-6, TNF-α and IL-12 in DH82 cells. In contrast, adenosine and ATP potentiated LPS-induced IL-10 production in DH82 cells. Moreover, adenosine, but not ATP inhibited LPS-induced expression of TLR4 in DH82 cells. These results suggest that conditions related to increased adenosine and/or ATP may play an important role in the inflammatory reactions.  相似文献   
10.
The temporal expression of estrogen receptor (ER)-α and ER-β mRNA was examined in male Japanese quails. Femurs of quails receiving 17β-estradiol underwent RTPCR and histochemical analysis 1 to 15 days after treatment. Untreated quails were used as controls (day 0). Between days 0 and 5, cells lining the bone endosteal surface differentiated into osteoblasts, which in turn formed medullary bone. Expression of ER-α was already observed on day 0 and increased slightly during bone formation whereas ER-β was hardly detected throughout this process. After osteoclasts appeared on the medullary bone surface, this type of bone disappeared from the bone marrow cavity (days 7~15). ER-α expression simultaneously decreased slightly and ER-β levels remained very low. These results suggest that estrogen activity mediated by ER-α not only affects medullary bone formation but also bone resorption.  相似文献   
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