Cinematographic analysis of the gait of lame horses

The gait characteristics of a horse with a non-articular fracture of the right supraglenoid tubercle are described. On physical examination, protraction of the injured limb was painful and limited in extent. Observation at the trot indicated that the horse was transferring weight onto the sound (left) diagonal by lowering the head, neck and trunk during the diagonal stance phase. There was little angular rotation of the shoulder and elbow joints present in the injured limb and consequently the toe barely cleared the ground during the swing phase.Analysis of high speed cinematography films was used to measure the stride parameters and quantify the gait asymmetries. The stance phase and the anterior phaseof the stride were significantly shorter in the right forelimb than the left (p<0.01) and the single support phase was minimized by increasing the overlap of the rightforelimb with the other limbs. Kinematic analysis showed a redistribution of body weight to relieve the load on the injured limb. During the right diagonal (RF- LH) stance phase the poll and withers sunk to their lowest point and the whole trunksegment advanced cranially over the left forelimb. In contrast during the left diagonal (LF-RH) stance phase the poll and withers were elevated and the trunk segment was shifted more caudally to transfer a greater proportion of the body weight onto the left hind limb rather than the painful right forelimb.     

Soil Phosphorus Variability: Scale-dependence in an Urbanizing Agricultural Landscape

We examine the hypothesis that human activity changes patterns of variance in soil P (Bray-1) concentrations across several spatial scales. We measured soil P concentrations and variability for each of four different land uses at three distinct levels of analysis. Land uses were remnant prairie, lawns, corn fields of cash grain farms, and corn fields of dairies in Dane County, Wisconsin (USA). For each land use type, levels of analysis were sites (an agricultural field, residential lawn or prairie, ranging in size from 100 m² to approximately 20 ha), 10-m plots within a site, and points within the 10-m diameter plot. The rank of mean soil P concentrations was cash grain > dairy > lawn > prairie. For all land use types, most of the variance was accounted for by site-to-site variation. Among-site variance was higher for human-dominated sites (0.55, 0.15, 0.14 [log (mg/kg)]² for cash grain, dairy, and lawn sites, respectively) than it was for prairies (0.07 [log (mg/kg)]²). However, prairies had the highest among-plot variation (0.04 [log (mg/kg)]²) compared to other sites (0.01, 0.002, and 0.01 [log (mg/kg)]² for cash grain, dairy, and lawn sites, respectively). The results indicate that in this watershed, human activity has increased the mean soil P and variance of soil P, and shifted the scale of variance to larger spatial extents. Human impacts on landscape pattern extend to soil properties that affect nutrient flow and eutrophication of surface waters. Because soil P turns over slowly, the legacy of altered soil P patterns may affect freshwaters for centuries.     

Increasing growth and feed efficiency of Juvenile Walleye,Sander vitreus (Mitchill, 1818), through novel,subsatiation, restrict/feed cycles from late summer into fall

The role of restricted feeding on the growth and feed efficiency (FE) of juvenile walleye, Sander vitreus, was investigated through two experiments. In the summer/fall experiment, 7.44‐g walleye were fed on one of the three schedules for 84 days: control (daily satiation feeding at 6% BW day^?1), D2 (2 days of feed deprivation, then fed at 12% BW day^?1 for 7 days, repeated throughout the study) and SS80 (subsatiation feeding involving 2 weeks of maintenance ration, then fed at 80% of the control group's feeding level). Juvenile walleye growth rates were significantly higher in the SS80 than in the control group, however, their growth rates in the D2 group were no different than in the control. Mean FE of the SS80 group (0.49), significantly exceeded those of the control (0.36) and D2 (0.28) groups. In contrast with the summer/fall experiment, no differences in growth rate were detected among the control, SS80 and D2 groups in the subsequent 84‐d spring experiment, where the juvenile walleye (97.45 g) were substantially larger, and their mean FE values were generally lower, with less distinction observed among the groups. Our findings indicate potential to increase growth and FE of juvenile walleye in advance of fall, by applying restrict‐feed schedules.     

Randomized, controlled study of inhaled fluticasone propionate, oral administration of prednisone, and environmental management of horses with recurrent airway obstruction

OBJECTIVE: To determine whether administration of glucocorticoids provides additional benefits to environmental management of horses with recurrent airway obstruction (RAO). ANIMALS: 28 horses with RAO. PROCEDURE: Horses were classified as having mild, moderate, or severe RAO. Within each category, horses were randomly assigned to receive inhaled fluticasone propionate, inhaled control substance, or oral administration of prednisone. During the 4-week study, horses were maintained outdoors and fed a pelleted feed. Clinical scores, pulmonary function, results of cytologic examination of bronchoalveolar lavage fluid (BALF), and adrenal gland function were determined before and 2 and 4 weeks after initiation of treatment. RESULTS: Clinical score and pulmonary function of all RAO-affected horses improved during the treatment period. After 4 weeks, clinical scores and pulmonary function of horses treated with a glucocorticoid were not different from those for the control treatment. In horses with severe RAO, treatment with fluticasone for 2 weeks resulted in significantly greater improvement in pulmonary function, compared with pulmonary function after treatment with prednisone or the control substance. Treatment with a glucocorticoid for 4 weeks and a low-dust environment did not have any effect on cellular content of BALF Treatment with prednisone for 2 weeks resulted in a significant decrease in serum cortisol concentration, compared with concentrations after administration of fluticasone or the control substance. CONCLUSIONS AND CLINICAL RELEVANCE: Environmental management is the most important factor in the treatment of horses with RAO. Early treatment with inhaled fluticasone can help accelerate recovery of horses with severe RAO.     

Effects of fertilization practices on aluminum fractions and species in a wheat soil

Purpose

To better understand the effect of fertilizer practices on soil acidification and soil organic matter (SOM) stocks in a rice-wheat system, a field experiment was conducted to (i) investigate the influence of fertilizer practices on the Al forms in solid phases and the distribution of Al species in water extracts and (ii) explore the relationship between the Al forms, the quantity and composition of SOM, and soil acidity.

Materials and methods

Seven fertilizer treatments including CL (no fertilizer), NK, PK, NPK, N₂PK (PK and 125 % of N), NP₂K (NK and 125 % of P), and organic fertilizer (OF) were applied to induce various changes in pH and SOM composition (i.e., total C and N contents, C/N ratio, and SOM recalcitrant indices) in a rice-wheat system. After 6-year cultivation, different pools of Al forms (i.e., amorphous Al; organically bound Al of varying stability; exchangeable Al; water-soluble inorganic Al³⁺, Al-OH, Al-F, Al-SiO₃, and Al-SO₄; and organic Al monomers) were quantified and related with SOM composition and soil pH during the wheat phase.

Results and discussion

Fertilizer types significantly changed soil pH and SOM composition and which explained 84 % of the variance of Al forms using redundancy analysis. An interaction between soil pH and SOM quality on Al forms also existed but only accounted for a very small (6 %) portion of the variation. Compared to CL and chemical fertilizer, OF practice with relative low SOM stabilization is likely to favor the formation of amorphous Al in order to bind more SOM. The decrease in exchangeable acidity and water-extractable Al via hydroxyl-Al precipitation but not in the form of organo-aluminum complexes evidenced this phenomenon. In contrast, chemical fertilizer input increased exchangeable Al and water extract Al (especially Al³⁺), partly at the expense of organically bound Al. The destabilization of organic-aluminum complexes was a mechanism of pH buffering evidenced by the increased soluble Al-dissolved organic matter (DOM) as soil pH decreases. Further, the magnitude of this trend was much greater for elevated N input compared with P input.

Conclusions

Chemical fertilizer with relative high SOM stabilization favored the formation of exchangeable Al and soluble Al resulting in soil acidification, whereas OF with relative low SOM stabilization tended to transform exchangeable Al and soluble Al to amorphous Al, thereby alleviating soil acidification and enhancing C stocks in a rice-wheat system.