The breaking strength (stress at failure) of equine third metacarpal bones, with and without clustered drill holes, was determined in vitro. Paired ossa metacarpalia II-IV of 39 horses (n = 39) between 2 and 7 years old were tested in palmarodorsal 3-point bending. Four treatments were compared. Clustered 2.7- or 3.5-mm drill holes, in a 4- or 7-hole pattern, were made in the dorsal cortex of the distal diaphysis of the left third metacarpal bone. Undrilled right third metacarpi were used as controls. Bones with clustered drill holes failed by an oblique fracture through 1 or more drill holes, whereas undrilled bones failed with a middiaphyseal transverse fracture. Clustered drill holes acted as a stress concentrator and significantly (P < 0.05) decreased the stress required for failure. However, differences in breaking strength between treatment groups were not significant (P > 0.05).

The fiber type, fiber size, and capillary geometric features were determined from the center of the proximal half of the left and right semitendinosus muscles in 5 mixed-breed dogs, 5 hound-type dogs, and 5 Beagles. There were no significant differences between the left and right muscles of each dog. Comparisons among the 3 groups of dogs revealed that the hound-type dogs had the largest fibers (type I and type II); however, the 3 groups were similar in their fiber-type percentages and their capillary geometric features.

This study has been carried out to investigate the augmenting or inhibiting effects of histamine, 5-hydroxytryptamine and their antagonists on the uterine motility. The uterine motility was represented by the magnitude of impulse and the frequency of uterine contraction which was counted by the number of waves on the recording paper. The inhibitory effect of phenoxybenzamine on the response to 5-hydroxytryptamine is the result of drug antagonism. Histamine stimlates or inhibits the motility of smooth muscle through H1 or H2-receptor. The uterine motility was increased through H1-receptor. Histamine induced relaxation by acting through H2-receptor.

To determine the prevalence and the morphological identification of two Eimeria species in fecal examinations, a total of 1092 fecal specimens collected during the period of March to December in 1987 was tested by means of flotation technique. The prevalence of two species was revealed as 1.83% and 0.92% in E. bukidnonensis and E. wyomingensis, respectively. The oocysts of E. bukidnonensis measured in range of 41.3 micro m to 49.4 micro m (mean 45.5+-1.7) x 28.8 micro m to 35.3 micro m (mean 32.2 +-1.2), and E. wyomingensis 36.9 micro m to 44.5 micro m (mean 39.8+-1.7) x 26.5 micro m to 29.9 micro m (mean 28.2+-0.9). The oocysts of E. bukidnonensis appeared darker and more robust than those of E. wyomingensis. The striations in the oocyst wall of E. bukidnonensis were more peculiar than in E. wyomingensis. Among the morphological characteristics, the widths could be reliably taken as a differential point of view for two Eimeria species

Gross and histological findings were obtained on cysts formed in the reproductive organs, particularly in the mesosalpinx, mesovarium, and fimbria, of 144 gilts and 37 sows. Of the 181 gilts and sows, 63 (34.8%) were found to have cysts which totaled 89. The number of cysts totaled 38 for the gilts and 51 for the sows, with relative frequencies of 18.1% 48.6%, respectively. The total number of cysts and the incidence were greater in the sows than in the gilts