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131.
Behavioral profiles of dog breeds 总被引:1,自引:0,他引:1
Breed behavior profiles were obtained by a method that was quantitative and free of personal biases. The profiles concerned 13 traits, eg, excitability, snapping at children, watchdog barking, and affection demand, which are of interest to people wanting dogs as pets. Authorities for the development of the profiles were 48 small animal veterinarians and 48 obedience judges, randomly selected from directories so as to represent equally men and women, and eastern, central, and western geographic regions of the United States. Each authority was asked to rank on each of the behavioral traits a list of 7 breeds chosen randomly from a list of 56 breeds. The data were analyzed in a custom-designed computer program that pooled the data and then ranked all 56 breeds on the basis of the 13 traits. The results indicated that some behavioral traits discriminate between breeds better than others. An examination of sample profiles indicated the feasibility of developing a statistically meaningful behavioral profile that integrates comparative rankings of several authorities balanced as to representation of geographic location, sex, and type of experience with dogs. 相似文献
132.
Relationships of implanted testosterone, dihydrotestosterone and estradiol-17 beta to collagen degradation and intramuscular collagen concentration and stability were determined. Intramuscular collagen content, solubility and shrinkage temperature and serum hydroxyproline were analyzed in groups of six rams, wethers, and wethers implanted with various levels of testosterone or dihydrotestosterone and groups of 10 rams, wethers and wethers implanted with estradiol-17 beta, dihydrotestosterone or a combination of these two steroids. Intramuscular collagen content in both experiments was higher (P less than .05) in muscles of rams than in muscles of wethers. Administration of the highest level of testosterone to wethers raised (P less than .05) total and insoluble intramuscular collagen to concentrations noted in rams. Administration of the testosterone metabolite, dihydrotestosterone, to wethers had no effect on intramuscular collagen. Administration of estradiol-17 beta to wethers tended to raise concentrations of intramuscular collagen so that they were no longer lower (P less than .05) than those in rams. Collagen stability as measured by solubility and thermal shrinkage temperature did not differ among rams, wethers or implanted wethers (P greater than .05). Increases in collagen accretion due to hormone administration were observed to be the result of increases in the insoluble portion of the intramuscular collagen (P less than .05). 相似文献
133.
D P Laflamme W J Miller M W Neathery R P Gentry D M Blackmon K R Logner A S Fielding 《Journal of animal science》1985,61(2):525-531
Sixteen 10-wk-old, phosphorus (P)-depleted Holstein bull calves were fed for 6 wk a control diet containing .08% P or P-supplemented diets containing .14, .20 or .32% P with supplemental P from two sources (CDP and Dynafos). The diets contained .45, .56, .66 and .87% Ca. After 5 wk of the experiment, the calves were dosed orally with 65Zn, and daily total fecal collections were initiated. At the end of the experimental period, the calves were killed and tissue samples were taken for total Zn and 65Zn analyses. Growth, feed intake and feed efficiency improved with increasing dietary P levels. Level of dietary P and Ca had little or no effect (P greater than .05) on total Zn content of rib, tibia, liver, heart, kidney, muscle or blood. Likewise, 65Zn absorption and content in most tissues were not affected (P greater than .05). The results do not preclude the possibility of some minor effects of P levels on Zn metabolism. However, it is apparent that when adequate Zn is fed, any effects are likely to be of little or no practical importance. 相似文献
134.
135.
H. Niklas und M. Miller 《Forstwissenschaftliches Centralblatt》1926,48(6):390-392
Ohne Zusammenfassung 相似文献
136.
Two experiments were conducted with ewes 9 to 11 days after estrus to determine whether the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are controlled differentially. In experiment 1, gonadotropin-releasing hormone (GnRH) was injected (100 (μg/ewe) at time = 0 min into ewes in four treatment groups. The treatment groups (9 ewes/group) were: 1) periodic iv sodium pentobarbital (NaPen) vehicle from 0 min; 2) periodic iv NaPen from 0 min; 3) vehicle iv for 120 min then iv NaPen from 120 min; 4) vehicle iv for 150 min then iv NaPen from 150 min. A surgical plane of anesthesia was maintained from the initiation of NaPen injection until the experiment ended. Jugular blood was sampled at 30-min intervals from ?30 to + 210 min for LH and FSH assays, and profiles of hormone concentrations were compared by time-trend analyses. GnRH released LH (P<.001) and FSH (P<.001), but NaPen did not affect the profiles of hormone concentrations; this indicated that NaPen did not reduce the ability of the pituitary to secrete gonadotropins in response to GnRH. Experiment 2 was a 2x2 factorial with ovariectomy (time = 0 hr) and NaPen as the main effects. One group of ovariectomized (n = 6) and one group of sham ovariectomized (n = 6) ewes were anesthetized only during surgery, while a group of ovariectomized (n = 7) and a group of sham ovariectomized (n = 6) ewes were kept at a surgical plane of anesthesia until 10 hr after surgery. Patterns of LH and FSH were compared in jugular blood collected hourly from 0 hr until 10 hr after surgery and in samples collected at 24 hr intervals from -24 to +72 hr of surgery. After ovariectomy, LH increased (P<.001) hourly and daily, but anesthesia suppressed (hourly, <.001 and daily, P<.005) these increases, which resulted in an interaction (hourly, P<.001 and daily, P<.01) of ovariectomy and anesthesia. FSH after ovariectomy increased hourly and daily (hourly, P<.02 and daily, P<.001), but the effect of anesthesia and interaction of ovariectomy and anesthesia were not significant. Because NaPen did not alter secretion of LH or FSH after exogenous GnRH in experiment 1 while it blocked the postovariectomy increase in LH but not FSH in experiment 2, we concluded that the postovariectomy increase in LH resulted from increased hypothalamic secretion of GnRH. The mechanisms responsible for the postovariectomy increase in FSH secretion are not identical to those for LH. The mechanisms that control the postovariectomy secretion of FSH might involve factors that are not suppressible by NaPen or, alternatively, the differences in LH and FSH release after ovariectomy might reflect the removal of ovarian factors that suppress FSH but not LH secretion in intact ewes. 相似文献
137.
A series of four trials was conducted to verify the published requirement of .26% total K in the diet and to identify response variables useful in an assay of the bioavailability of K in feedstuffs for the young pig. Purified diets were supplemented with K at four levels as KC2H3O2 in three trials and as KHCO3 in the fourth trial. In the first three trials, the requirement was estimated by least-squares analysis of a linear-plateau response of average daily gain. Additional measures in each trial were taken for linear response to dietary K levels. The three estimates of K requirement obtained were .30, .33 and .26% total K in the diet. These three estimates were not found to be inconsistent with the published value of .26% total K in the diet. Various urinary and hematological measures also were examined during the four trials for linear response to dietary K levels. Plasma K was the only hematological response to show a significant linear relationship to dietary K levels. Urinary K concentrations and daily excretion showed a highly significant linear response to dietary K levels. Based on these results, a K bioavailability assay using urinary K measures as the primary response variable and plasma K as the secondary response variable seems the most promising. 相似文献
138.
Seventeen field trials were conducted at 14 sites in Idaho, Oregon, and Washington to assess efficacy of lindane (gamma HCH) as a seed treatment for control of wireworms on wheat. The performance of lindane-treated seeds was compared with that of seeds treated with fungicide only, in plots treated with fonofos before planting and in untreated control plots. Plant stands were affected negatively by wireworms in control plots in different locations. Generally, lindane and fonofos protected spring wheat but not winter wheat against wireworms, based on plant stand counts and yields. Plant counts in lindane plots were significantly greater than those in control plots in six out of seven spring wheat trials, but in only one out of 10 winter wheat trials. Yields were significantly greater in two spring wheat trials and one winter wheat trial. Performance of fonofos was similar to that of lindane. 相似文献
139.
140.