The hindlimb of the grasscutter (Thryonomys swinderianus, Temminck‐1827) was studied using 12 adult (≥6 months) rats of either sex with the mean weights of 1.42 ± 0.20 kg and 0.82 ± 0.13 kg for buck (n = 6) and doe (n = 6), respectively (p < .05). Characteristics of the bones were studied by gross observation after their preparation. Measurements of different segments of the hindlimb were also taken, giving a total average length of 31.80 cm. Correlation coefficients between length of bone and weight of rats were positive (p < .05) in bucks for all bone segments, except the pes (p > .05), whereas those in does were all non‐significant (p > .05), with significant sexual dimorphism in the relationships. The average total number of bones in the hindlimb was 92, with no apparent sexual dimorphism. The bones of the hindlimb revealed important differences and similarities in morphology with those of other rodents. The Os coxae presented a relatively large obturator foramen, formed by the ramus of the ischium and shaft of the pubis. The femur had a body and two extremities with a prominent head, well‐defined neck and trochanter. The fibula, a slender bone with triangular‐shaped proximal extremity, ran down the length of tibia with proximal attachment (via cartilage) and distal fusion, leaving an extensive interosseus space. The pes revealed eight tarsals and four metatarsals; each of the metatarsals showed three phalanges. 相似文献
Tropical Animal Health and Production - The experiment was conducted to evaluate changes in feed consumption and water intake among broiler chickens subjected to melatonin treatment during the... 相似文献
Six Nubian pack donkeys were used to determine variations in rectal temperature (RT), respiratory rate (RR), and heart rate (HR) during the early rainy season. The donkeys exhibited a diurnal range of RT, RR, and HR of 34.7 to 38.7°C, 15 to 75 breaths/minute, and 36 to 72 beats/minute, respectively, with peak mean values at 2:00 pm and a trough shortly after sunrise (7:00 am). The amplitude of the diurnal rhythm of RT and RR was not correlated with the diurnal range of ambient temperature (AT) and relative humidity (RH). Although mean diurnal RTs were positively correlated with corresponding ATs, mean daily RTs were not significantly correlated with corresponding ATs. Diurnal and daily variations in RT of donkeys, like those of other ungulates, therefore, appear to reflect an endogenous rhythm, which may be largely independent of fluctuations in environmental thermal load. The mean maximum AT and RH, and the corresponding RR and HR values, fell above the normal range for donkeys in the tropics. The season was meteorologically stressful to the donkeys, imposing significant changes in the RT, RR, and HR parameters requiring responses to maintain homeostasis. The values of the amplitude in RT, RR, and HR obtained in individual donkeys were higher than the corresponding values obtained during the hourly recordings, indicating that it is more important to evaluate the individual's vital parameters in reaching conclusion of fitness for work in donkeys. The hourly recordings have shown the hours of the day (11:00 am to 4:00 pm) that are potentially meteorologically stressful for donkeys to be used for packing during the season. 相似文献
Tropical Animal Health and Production - The aim of the study was to determine some ergonomic parameters of donkeys administered with Pycnogenol® (PYC) and subjected to packing during the... 相似文献
The research aimed to determine the transport velocities of aniline (AN) and nitrobenzene (NB) in sandy sediment so as to predict the pollution plume in sandy aquifer. The transport velocities of organic compounds in aquifer depend on various factors. This research also evaluated the effects of compound type, single or mixture solute systems, pore-water velocity (v), and pH on the transport velocities of AN and NB. These results will facilitate more precise determination of transport velocities.
Materials and methods
Column experiments containing sorption and desorption periods were conducted using typical sandy sediment from JiangHan Plain, China. Special emphasis was placed on the variation of compounds, solute systems, v from 4.5 to 10 cm h?1, and pH from 5 to 8.5. The transport curves of AN and NB were simulated using different sorption models coupled in HYDRUS-1D and the partition coefficient, Kd, was determined by inverse solution. The retardation coefficient (R) and transport velocity (1/R) were calculated based on Kd and the basic properties of the column. The transport velocities of AN and NB in various experimental conditions were compared and discussed.
Results and discussion
The linear non-equilibrium two-site (L2Site) sorption model coupled in HYDRUS-1D best described the sorption of AN and NB during the transport process in the sandy sediment. The 1/R values of AN and NB were 0.47–0.67 m and 0.16–0.21 m, respectively. AN transported three times faster than NB in both single and mixture systems. Lower v enhanced the transport of AN but displayed limited impact on the transport of NB in single solute system. In mixture solute system, the 1/R values of AN tended to decrease and NB increase at lower v, which suggested an interference between AN and NB transports. Both transport velocities of AN and NB potentially increase with pH.
Conclusions
AN and NB can transport 0.47–0.67 m and 0.16–0.21 m, respectively, when groundwater flows 1 m at various experimental conditions. The transport velocities of AN and NB depend on the type of compounds, single or mixture solute system, v, and pH. All the factors should be considered when we determine the parameter, transport velocities, for prediction of pollution plume.
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