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The chemical analysis of dried cooked potato flake suggests that the material might be used in diets for broilers. Starter and finisher diets containing 0, 10, 20 and 40% potato flake in place of maize meal were formulated, and fed ad libitum in pellet form to broilers. Performance of the birds and characteristics of the pellets were measured.

The performances of birds given diets containing 0, 10 and 20% potato were similar. Birds given the diet containing 40% potato grew at a slower rate, ate less food but converted food as efficiently as birds receiving other diets.

Wetness of the litter and hardness of the pellets both increased as the proportion of potato in the diet increased, and these are suggested as the main factors limiting the proportion of potato used in the diet. It is proposed that these factors may be overcome by attention to the litter and by feeding diets containing potato in smaller sized particles.  相似文献   

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This study was designed to evaluate the efficacy of a citronella bark collar and a new, scentless spray bark collar in a veterinary hospital or a similar kennel-type environment. Forty-one dogs were included in the study. The efficacy of each collar was evaluated independently in comparison to control as well as in a crossover design. Thirty of the dogs were evaluated with the citronella collar, with 76.7% showing a reduction in barking. Twenty-nine dogs were evaluated with the scentless collar, with 58.6% showing a reduction in barking. The improvement over the control collars was statistically significant with both the citronella and scentless collars.  相似文献   
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Shrink a clump of matter to a few hundred atoms, and it enters a curious netherworld. Neither ordinary solids nor conventional small molecules, such atomic clusters have unique chemical, optical, and electronic properties. Since the mid-1970s, when advances in synthesizing and analyzing clusters first enabled researchers to explore this netherworld in earnest, clusters have nucleated a sizable field. Many of its participants gathered in Chicago on 15 to 22 September for the Sixth International Symposium on Small Particles and Inorganic Clusters, the first of the series to be held in the United States. At the top of the agenda for the 300 attendees were the field's old stalwarts, various kinds of metal clusters; its current darlings, the carbon clusters known as fullerenes; and a possible future superstar, silicon clusters.  相似文献   
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REASON FOR PERFORMING STUDY: Conditioning by early training may influence the composition of certain musculoskeletal tissues, but very few data exist on its effect during growth on tendon structure and function. OBJECTIVES: To investigate whether conditioning exercise in young foals would lead to any ultrasonographically detectable damage to the superficial digital flexor tendon or an increase in cross-sectional area (CSA). METHODS: Thirty-three Thoroughbred foals reared at pasture were allocated to 2 groups: control (PASTEX) allowed exercise freely at pasture; and CONDEX, also at pasture, began conditioning exercise from mean age 21 days over 1030 m on a purpose-built oval grass track, for 5 days/week until mean age 18 months. Foals were observed daily, and underwent orthopaedic examination monthly. Ultrasonographic images of the superficial digital flexor tendon (SDFT) at the mid-metacarpal level of both forelimbs were obtained in all foals at ages 5, 8, 12, 15 and 18 months. CSA was validated (r(2) = 0.89) by determining CSA from digital photographs of the transected SDFT surface from 12 of the horses necropsied at age 17.1 months. RESULTS: here was no clinical or ultrasonographic evidence of tendonopathy in either group and the greatest increase in mean CSA in both groups occurred between age 5 and 8 months. Across all age categories, there was no significant difference in mean CSA between the left and right limbs, or colts and fillies; there was a trend towards a larger CSA in the CONDEX group (P = 0.058). CONCLUSIONS: There was no conclusive evidence for a structural adaptive hypertrophy of the SDFT, probably because the regimen was insufficiently rigorous or because spontaneous pasture exercise may induce maximal development of energy storing tendons. POTENTIAL RELEVANCE: A moderate amount of early conditioning exercise against a background of constant exercise at pasture is not harmful to the development of the flexor tendons.  相似文献   
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