Utilization of elastic energy during weight exercises differs under stable and unstable conditions.

AIM: The study compares the power outputs in concentric phase of chest presses and squats performed without and with countermovement on stable and unstable support surface, respectively. METHODS: A group of 16 physical education students performed randomly in four different days 3 repetitions of: 1) barbell chest presses on the bench and Swiss ball, respectively, and 2) barbell squats on stable support base and Bosu ball, respectively. Exercises were performed without and with countermovement (CM) using maximal effort in concentric phase of lifting. Initial weight of 20 kg increased by 10 kg or 5 kg (at higher loads) up to at least 85% of previously established 1RM under stable conditions. A PC based system FiTRO Dyne Premium was used to monitor force and velocity and to calculate power. As a parameter of the capability to use elastic energy was considered the difference in mean power in concentric phase of weight exercises (ΔP) performed with and without CM. RESULTS: There were higher power outputs in concentric phase of CM chest presses as compared to those performed from quiet position on the chest under both stable and unstable conditions. This enhancement of power due to CM was rather modest at lower weights and become more pronounced with increasing weights reaching a maximum at 57.1% 1RM on stable and at 47.6% 1RM on unstable support surface. Lifting heavier weights not only failed to increase the enhancing effect but led to its decline. Similar trend was observed during squats with maximal enhancement of power in concentric phase of lifting at about 80% 1RM under both conditions. The ΔP was significantly lower during chest presses on Swiss ball than on the bench, however, only at higher weights lifted (≥60% 1RM). On the other hand, the ΔP during squats performed on Bosu ball and on stable support base did not differ significantly across all weights lifted. CONCLUSION: The ability to utilize elastic energy during CM chest presses is more profoundly compromised under unstable than stable conditions, namely at higher weights lifted. On the other hand, there is similar enhancement of power in concentric phase of CM squats on stable and unstable support surface regardless of weights lifted. Besides the type of exercise, this may be ascribed to different degree of instability of devices used (Swiss ball vs. Bosu ball).

The effect of 6-week combined agility-balance training on neuromuscular performance in basketball players.

AIM: The study evaluates the effect of 6-week combined agility-balance training on neuromuscular performance in basketball players. METHODS: Subjects divided into experimental (EG, n = 17) and control group (CG, n = 17) underwent a combined agility-balance training (in duration of 30 min) for a period of 6 weeks (4-5 sessions/week). Both groups performed reaction tasks similar to game-like situations, however EG on wobble boards and CG on stable surface. Prior to and after the training parameters of agility, balance, speed of step initiation, strength differentiation accuracy, and explosive power of lower limbs were evaluated. Postural stability was assessed under both static and dynamic conditions (wobble board) with eyes open and eyes closed, respectively. The velocity of the centre of pressure (COP) was registered at 100 Hz by means of posturography system FiTRO Sway check based on dynamometric platform. Using FiTRO Reaction check simple and multi-choice reaction times were measured. The same system was applied to evaluate the agility performance including reaction and movement task. Speed of step initiation was measured using FiTRO Dyne Premium. Jumping abilities were evaluated by means of FiTRO Jumper (10-seconds maximal jumps, Countermovement jump, Squat jump, Drop jump). Using the same system, the subject´s ability to match 50 % of their maximal height of the jump was evaluated. RESULTS: Results showed that a combined agility-balance training improved dynamic balance not only under visual control but also in eyes closed conditions. Training also increased run-out speed that likely contributed to better agility performance, reduced ground contact time during drop jump, and improved the ability to differentiate the force of muscle contraction during repeated jumps. However, such training has been found to be insufficient to improve both simple and multi-choice reaction time, and jumping performance. On the other hand, control group failed to show any significant improvement in examined abilities except for enhancement of jumping performance (Pact, Δ CMJ & SJ). CONCLUSION: It may be concluded that balance exercises performed simultaneously with reaction tasks represent an effective means for improvement of neuromuscular performance in elite athletes.

Clinical utility of miRNA-1, miRNA-29g and miRNA-133s plasma levels in prostate cancer patients with high-intensity training after androgen-deprivation therapy.

The randomized trials showed that the addition of training resistance program to androgen-deprivation therapy (ADT) had many beneficial effects for prostate cancer (PC) patients (significant protective effect on the volume of muscle mass) and the studies have revealed a panel of miRNAs, which are deregulate in PC and may serve as promising biomarkers of PC risk. The primary aim of our present study was to investigate the effect of exercise training to changes in body composition (muscle strength) and the secondary endpoint was to investigate the impact of an exercise training program on plasma levels of selected myogenic microRNAs (miRNAs) (miRNA-1, miRNA-29b, and miRNA-133) in PC patients undergoing the ADT. Effect of ADT and exercise intervention showed significant increase (experimental group vs. control group) the changes in body composition, free testosterone levels, IL-6 and plasma levels of myogenic miRNAs and significant reduced insulin serum levels. In conclusion, resistance training with ADT in the treatment of PC significantly changed the physical and metabolic function and the plasma levels of specific myogenic miRNAs. Our data support with the other publicized results.

Reliability and methodological issues of power assessment during chest presses on unstable surface with different weights.

AIM: The study compares the reliability of peak power (Ppeak) and mean power in acceleration (Pmean acc) and entire concentric phase (Pmean total) of chest presses on the bench and unstable Swiss ball with different weights. METHODS: A group of 32 fit men performed over 2 testing sessions 3 trials of barbell chest presses on the bench and Swiss ball, without and with countermovement, with weights of 40, 60 and 80% 1RM. RESULTS: High values of correlation coefficients (above .80) and no significant differences between trials signify stability of measurement under both stable and unstable conditions. When chest presses were performed on the bench, ICC and SEM% values were in range .97 to .98 and 7.6 to 7.7%, respectively for Pmean total, .96 to .98 and 9.1 to 9.6%, respectively for Pmean acc, and .94 to .97 and 9.2 to 10.0%, respectively for Ppeak. Their values during chest presses on a Swiss ball ranged from .93 to .96 and 8.4 to 9.1%, respectively for Pmean total, from .87 to .90 and 11.7 to 12.2%, respectively for Pmean acc, and from .79 to .82 and 12.1 to 13.4%, respectively for Ppeak at weights of 40 and 60% 1RM, and from .70 to .76 and 17.6 to 19.8%, respectively at weight of 80% 1RM. CONCLUSION: Measurement of peak and mean power during unstable chest presses provides reliable data comparable to those obtained during bench presses under all conditions tested. However, peak values of power measured during unstable chest presses with weights ≥80% 1RM should be interpreted with caution.

Brain enzyme and clinical alterations induced in rats and mice by nitroaliphatic toxicants.

The effects of a single subcutaneous (s.c.) injection of the nitroaliphatic toxicants 3-nitropropanol (NPOH) and 3-nitropropionic acid (NPA) dissolved in physiological saline solution were studied in mice and rats, respectively. Clinical signs observed in both NPOH-treated mice and NPA-treated rats included depression, abnormal motor activity, and recumbency. Succinate dehydrogenase (SDH) activity, demonstrated histochemically in frozen brain sections, was markedly reduced in intoxicated mice and rats. The SDH activity of mitochondrial preparations from brains of intoxicated mice and rats was diminished to 18-24% of control values, although the activity of another mitochondrial flavoprotein enzyme, alpha-glycerophosphate dehydrogenase (alpha-GPDH), was not altered.

Effect of head-down bed rest on the neuroendocrine response to orthostatic stress in physically fit men.

The role of neuroendocrine responsiveness in the development of orthostatic intolerance after bed rest was studied in physically fit subjects. Head-down bed-rest (HDBR, -6 degrees, 4 days) was performed in 15 men after 6 weeks of aerobic training. The standing test was performed before, after training and on day 4 of the HDBR. Orthostatic intolerance was observed in one subject before and after training. The blood pressure response after training was enhanced (mean BP increments 18+/-2 vs. 13+/- 2 mm Hg, p<0.05, means +/- S.E.M.), although noradrenaline response was diminished (1.38+/-0.18 vs. 2.76+/-0.25 mol.l(-1), p<0.01). Orthostatic intolerance after HDBR was observed in 10 subjects, the BP response was blunted, and noradrenaline as well as plasma renin activity (PRA) responses were augmented (NA 3.10+/-0.33 mol.l(-1), p<0.001; PRA 2.98+/-1.12 vs. 0.85+/-0.15 ng.ml(-1), p<0.05). Plasma noradrenaline, adrenaline and aldosterone responses in orthostatic intolerant subjects were similar to the tolerant group. We conclude that six weeks of training attenuated the sympathetic response to standing and had no effect on the orthostatic tolerance. In orthostatic intolerance the BP response induced by subsequent HDBR was absent despite an enhanced sympathetic response.

In vivo indicators of pathologic ruminal sulfide production in steers with diet-induced polioencephalomalacia.

Two groups of 3 120-160-kg Holstein steers were fed a diet high in carbohydrate and low in long fiber and either with or without added sodium sulfate. Prior to and during the course of feeding the experimental diet, the concentrations of rumen hydrogen sulfide gas and rumen fluid sulfide were determined by a simple sulfide detector tube method and by sulfide-selective electrode, respectively. Other measurements included rumen fluid pH, blood creatine kinase, and blood sulfhemoglobin. Two of the 3 steers fed the high-sulfate diet developed signs and lesions of polioencephalomalacia. Clinical signs included episodic ataxia and blunted or absent menace reaction. Increased ruminal H2S gas concentrations occurred in all 3 steers consuming the diet with added sulfate. The onset of clinical signs coincided with the onset of elevated H2S concentrations. These increases were 40-60 times the values measured in the steers consuming the diet without added sulfate. In contrast, increases in rumen fluid sulfide concentrations usually rose to 4 times that of control steers. The steers fed an identical diet but without added sulfate exhibited no signs or lesions of polioencephalomalacia and no elevations of sulfide in rumen gas or fluid. All steers had a modest decrease in rumen fluid pH associated with the transition to the concentrate diet. No significant changes were observed in any of the blood measurements of any of the steers. An additional pair of steers was fed the experimental diet with or without added sulfate to compare the ruminal H2S gas concentrations estimated by H2S detector tubes with those estimated by a different method of analysis utilizing charcoal trapping of H2S, conversion to sulfate, and measurement of the sulfate. Both methods yielded comparable estimates of H2S concentration. Overall, these data indicate that changes in rumen gas cap H2S concentrations are larger than changes in rumen fluid sulfide concentration and the estimation of rumen gas cap H2S concentration may be a practical approach to detecting pathologic increases in ruminal H2S gas. This simple, rapid, minimally invasive method should be useful for estimating the H2S content of ruminal gas under field conditions.

Comparison of four methods for forage nitrate analysis.

Twenty forage samples were collected and selected for variation in nitrate content. Each forage samples was analyzed 4 times by 4 different methods: diphenylamine spot plate, spectrophotometric, nitrate-selective electrode, and high-performance liquid chromatographic. Five feed extracts were spiked with 2 different amounts of nitrate and analyzed by each method. The spectrophotometric and nitrate-selective electrode had similar percent recoveries, which were close to 100%. The nitrate-selective electrode method had the least variation of the 4 methods. The diphenylamine spot plate method had the poorest average recovery, greatest variation, and was the least accurate. The average coefficients of variation for all samples within a method were 15%, 12%, 6.4%, and 16 for the diphenylamine spot plate, spectrophotometric, nitrate-selective electrode, and high-performance liquid chromatographic methods, respectively. The variation in the nitrate-selective electrode method was lower (P < 0.05) than the other methods. The results from this study suggest that the nitrate-selective electrode method is more accurate and precise than the other methods of analysis tested.

Sulphide-induced polioencephalomalacia in lambs.

Polioencephalomalacia (PEM) was induced in four of 10 lambs by the administration of a sulphide solution into the oesophagus at 20 min intervals for a period of 40 to 120 min. Signs of neurological dysfunction occurred in all 10 lambs during that time and included stupor, visual impairment and seizures. Gross autofluorescent and microscopic lesions in cerebrocortical grey matter were present as soon as 20 h after sulphide administration and were indistinguishable from lesions in naturally occurring disease. These findings, when considered together with an earlier study that revealed an association between high ruminal concentrations of sulphide and PEM, indicate that this disease can result from sulphide toxicosis, independent of the metabolic status of thiamine.

Effects of neutering on bodyweight, metabolic rate and glucose tolerance of domestic cats.

Few controlled studies have been made of the possible mechanisms and physiological consequences of weight gain after cats have been neutered. In this study, six male and six female cats were gonadectomised and compared with five entire male and six entire female cats, before they were neutered and one and three months later. The neutered males gained significantly more weight (mean [SEM] per cent) than the entire males (30.2 [5.2] v 11.8 [2.3]) and the entire females gained 40.0 (7.3) v 16.1 (3.3) per cent, (P < 0.05). The castrated males gained more weight as fat than the sexually intact males (22.0 [3.3] v 8.8 [4.5] per cent, P < 0.05). There was a significant increase (P < 0.05) in daily food intake after neutering. Spayed females underwent a significant decrease in fasting metabolic rate (83.7 [5.5] v 67.2 [2.3] kcal/kg bodyweight0.75/day P < 0.05). Gonadectomy had minimal effects on serum thyroid hormone concentrations, the resting or fasting metabolic rates in males, or on indices of glucose tolerance.

Effects of weight gain and loss on metabolic rate, glucose tolerance, and serum lipids in domestic cats.

Weight gain is a common problem in domestic cats, but little is known about its metabolic effects. The purpose of this study was to determine the effects of diet-induced weight gain and subsequent weight loss on metabolic rate, body composition, and glucose tolerance. Gain of approximately 20 per cent body weight (divided approximately equally between fat and fat-free mass) over three months resulted in insulin resistance in females, indicated by increases in basal insulin concentration (68.2+/-7.9 to 119+/-16.5 pmol litre(-1), P<0.05), insulin peak response to glucose (241.1+/-31.6 to 315.0+/-23.0 pmol litre(-1), P<0.05), and deltaI/deltaG (14.2+/-2.6 to 18.1+/-1.3 pmol mmol(-1), P<0.05) compared with pre-gain values. The same numerical trend was noted in male cats, however, changes were not significant (P>0.05). Alterations in serum lipids included significant (P<0.05) elevations in triglyceride concentrations in male cats and decreased beta-lipoprotein concentrations in both genders. Weight loss over three months normalised basal insulin, insulin response to glucose, and serum triglyceride concentrations, and resulted in significant (P<0.05) decreases in serum concentrations of beta- and prebeta-lipoproteins, cholesterol, and triiodothyronine. Diet-induced weight gain of three months' duration, followed by three months' maintenance of increased body weight did not affect fasting or resting metabolic rate. Development and severity of impaired glucose tolerance, insulin resistance, and other changes may be affected by duration and possibly severity of weight gain.

Serum zinc, chromium, and iron concentrations in dogs with lymphoma and osteosarcoma.

We compared serum concentrations of zinc, chromium, and iron in dogs with cancer to those of normal dogs. Dogs with lymphoma (n = 50) and osteosarcoma (n = 52) were evaluated. Dogs with lymphoma had significantly lower (P = .0028) mean serum zinc concentrations (mean +/- SD; 1.0 +/- 0.3 mg/L) when compared to normal dogs (1.2 +/- 0.4 mg/L). Dogs with osteosarcoma also had lower mean serum zinc concentrations (1.1 +/- 0.4 mg/L), but this difference was not significant (P = .075). Serum chromium concentrations were significantly lower in dogs with lymphoma (2.6 +/- 2.6 microg/L, P = .0007) and osteosarcoma (2.4 +/- 3.1 microg/L, P = .0001) compared to normal dogs (4.7 +/- 2.8 microg/L). Serum iron concentrations and total iron-binding capacity were significantly lower in dogs with lymphoma (110.8 +/- 56.7 microg/dL, P < .0001, and 236.6 +/- 45.6 microg/dL, P < .0001, respectively) and osteosarcoma (99.6 +/- 49.3 microg/dL, P < .0001, and 245.0 +/- 43.8 microg/dL, P = .0011, respectively) when compared to normal dogs (175.1 +/- 56.7 microg/dL and 277.1 +/- 47.4 microg/dL). Mean ferritin concentration was significantly higher in dogs with lymphoma (1291.7 +/- 63.0 microg/L) than in normal dogs (805.8 +/- 291.1 microg/L, P < .0001) and dogs with osteosarcoma (826.5 +/- 309.2 microg/L, P < .0001). Further investigation is needed to explore the clinical significance of these mineral abnormalities in dogs with cancer.

Dietary fat and exercise conditioning effect on metabolic parameters in the horse.

Four isocaloric diets containing 4, 8, 12 and 16% dietary fat (as soybean oil) were fed to four horses at four intervals according to a Latin square design. After 3 weeks of conditioning at each interval, diet effects were evaluated by trotting all horses at 3.2 m/sec for 6 hours. Pre- and posttrotting responses were measured in muscle and liver glycogen, serum long-chain fatty acids, serum electrolytes, serum enzymes, serum cholesterol, plasma glucose, packed cell volume and hemoglobin. Dietary fat was highly correlated with exercise-induced plasma glucose changes and with cholesterol concentrations. Regardless of the diet, linoleate concentration was about eight times higher than that of the other fatty acids, and it increased slightly as dietary fat levels increased. Stearate concentration also increased with increasing dietary fat but palmitic and oleic acid decreased. Increases in fat intake also resulted in slight increases in liver glycogen at the resting level. Conditioning resulted in a significant decrease in exercise-induced fluctuations of serum enzymes and electrolytes but significantly increased elevations of plasma long-chain fatty acid concentrations. Resting muscle glycogen increased by 37% during the study as a result of conditioning, but there was no effect on liver glycogen at rest or after exercise. Feeding of the four levels of dietary fat in the form of soybean oil had no adverse effects and proved a safe and efficient method of providing concentrated energy to working horses.

Cecal short-chain fatty acids in experimental rabbit mucoid enteropathy.

Short-chain fatty acid concentrations were measured in the cecal contents of 9 healthy rabbits and 20 rabbits with experimentally induced mucoid enteropathy. In control rabbits, cecal concentration of acetate was the most abundant, followed by that of butyrate and propionate--a feature distinguishing rabbits from most other mammals. In mucoid enteropathy, cecal acetate and butyrate concentrations were lower, whereas propionate, isobutyrate, valerate, and isovalerate were increased. The results indicated that there were abnormal fermentation and cecal maldigestion in rabbits with mucoid enteropathy.

Efficacy of 4-methylpyrazole for treatment of ethylene glycol intoxication in dogs.

4-Methylpyrazole (4-MP), an alcohol dehydrogenase inhibitor, was administered to dogs to treat ethylene glycol (EG) intoxication. Eleven dogs were given 10.6 g of EG/kg of body weight; 5 dogs were treated with 4-MP 5 hours after EG ingestion and 6 dogs were treated with 4-MP 8 hours after EG ingestion. 4-Methylpyrazole was administered IV as a 50-mg/ml [corrected] solution in 50% polyethylene glycol: initial dose, 20 mg/kg; at 12 hours after initial dose, 15 mg/kg; at 24 hours after initial dose, 10 mg/kg; and at 30 hours after initial dose, 5 mg/kg. Physical, biochemical, hematologic, blood gas, serum and urine EG concentrations, and urinalysis findings were evaluated at 0, 1, 3, 6, 9, 12, 24, 48, 72 hours, and at 1 week and 2 weeks after EG ingestion. Dogs of both groups developed clinicopathologic signs associated with EG intoxication, including CNS depression, hyperosmolality, high anion gap metabolic acidosis, polydipsia, polyuria, calcium oxalate monohydrate and dihydrate crystalluria, and isosthenuria. Fractional excretion of sodium was increased in all dogs between 1 and 9 hours after EG ingestion, but remained increased beyond 24 hours only in the 2 dogs treated at 8 hours after EG ingestion that developed acute renal failure. All dogs treated 5 hours after EG ingestion recovered without morphologic, biochemical, or clinical evidence of renal impairment. Of the 6 dogs treated 8 hours after EG ingestion, 2 developed acute renal failure. One of the dogs treated 8 hours after EG ingestion remained isosthenuric for 2 months, but did not manifest any other signs of renal impairment.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of ethanol and 4-methylpyrazole as treatments for ethylene glycol intoxication in cats.

The efficacy of 4-methylpyrazole (4-MP) and ethanol as treatment for ethylene glycol (EG) intoxication in cats was compared. Twenty-two cats were assigned at random to 6 experimental groups. Cats of 1 experimental group were given only 4-MP; those of another experimental group were given only EG. Cats of 3 experimental groups were intoxicated with EG and given 4-MP at 0 hour or 2 or 3 hours after EG ingestion, and those of 1 experimental group were given EG and treated with ethanol 3 hours after EG ingestion. Physical, biochemical, hematologic, blood gas, serum and urine EG concentrations, and urinalysis findings were evaluated at 0, 1, 3, 6, 9, 12, 24, 48, and 72 hours, 1 weeks, and 2 weeks after EG ingestion or 4-MP treatment in cats of the 4-MP only group. The half-life of EG and percentage of ingested EG excreted unchanged were determined for each group. 4-Methylpyrazole treatment at 0 hour was most effective at preventing metabolism of EG. 4-Methylpyrazole was not effective in preventing development of renal failure when given 2 or 3 hours after EG ingestion. Ethanol given 3 hours after EG ingestion was successful in preventing development of renal dysfunction in 2 of the 6 cats treated 3 hours after EG ingestion. Of the remaining 4 cats treated with ethanol, 2 developed transient renal dysfunction and 2 developed acute oliguric renal failure and were euthanatized. 4-Methylpyrazole given 2 or 3 hours after EG ingestion was less effective in preventing EG metabolism than was ethanol given 3 hours after EG ingestion. Therefore 4-MP, at the dose found to be effective in dogs, cannot be recommended as an alternative to ethanol for treatment of EG intoxication in cats.

Clinical and biochemical alterations in calves with nutritionally induced polioencephalomalacia.

Polioencephalomalacia (PEM) was induced in calves by feeding a semipurified, low-roughage diet of variable copper and molybdenum composition. Two formulations resulting in Cu-insufficient and Cu-sufficient forms of the diet were fed (n = 10 and 4 calves, respectively); both diets induced PEM. Clinical signs of disease developed as early as 15 days after transition to the experimental diets and included impaired vision, decreased response to external stimuli, and abnormal gait. Grossly evident cerebrocortical lesions consisted of laminar areas of cavitation and/or autofluorescence seen under UV illumination. Hepatic Cu concentration was decreased in calves fed the Cu-insufficient diet, but not below normal range. During the course of feeding either diet, rumen pH decreased, rumen volatile fatty acid concentrations increased, rumen and blood lactic acid concentrations increased, and rumen and plasma thiamine concentrations increased. The thiamine pyrophosphate effect on erythrocyte transketolase activity was unaltered in calves of either diet group. This nutritionally induced form of PEM does not appear to be related to Cu deficiency or reduction in plasma or rumen thiamine concentration.

Inhibition of canine and feline alcohol dehydrogenase activity by fomepizole.

OBJECTIVE: To determine and compare substrate specificity and kinetic rate constants of feline and canine alcohol dehydrogenase (ADH) with ethanol (EtOH) and ethylene glycol (EG) as substrates in vitro, with and without fomepizole. SAMPLE POPULATION: Livers from 3 dogs and 3 cats. PROCEDURE: Canine and feline ADH activity, in cytosolic fractions of homogenized liver, was determined by use of various concentrations of nicotinamide adenine dinucleotide (NAD), EtOH, or EG as substrates. Initial reaction velocities were calculated, and kinetic inhibition rate constants (Ki) for fomepizole were determined. RESULTS: Substrate specificity of canine and feline ADH for EtOH or EG was not significantly different. A 2-fold difference was detected in the maximal velocity of canine, compared with feline, ADH, using either substrate. Fomepizole Ki in feline hepatic homogenates was significantly greater than Ki in canine hepatic homogenates when either EtOH or EG was used as substrate (10- and 30-fold, respectively). A 6-fold increase in the concentration of fomepizole was required to achieve ADH inhibition, with feline homogenates equivalent to those of canine homogenates. CONCLUSIONS AND CLINICAL RELEVANCE: Feline ADH has lower enzymatic capacity for turnover or is less concentrated in liver than canine ADH with regard to EtOH and EG catalysis. Canine ADH was more effectively inhibited by fomepizole than feline ADH. Results suggest that higher dosages of fomepizole may be more effective to treat cats with EG intoxication than dosages reported to treat dogs.

Bioelectrical impedance and zoometry for body composition analysis in domestic cats.

Zoometric measurements and bioelectrical impedance analysis were evaluated as methods of body composition determination in healthy cats. Zoometric and impedance measurements were taken on 22 anesthetized adult cats of various ages, genders, breeds, and body weights. The cats were then euthanatized. The bodies were processed through a tissue homogenizer and free-catch specimens were taken, freeze-dried, and analyzed for total body water, protein, fat, potassium, and ash content. Stepwise regression analysis was implemented to identify statistically significant relationships between the chemically determined dependent variables (total body water, protein, potassium, fat-free mass, fat mass, and percent body fat) and the zoometric measurements, with or without bioelectrical impedance analysis. Statistical analysis revealed high correlations between the dependent variables and the corresponding predicted values of those variables. Body weight alone was a poor predictor of body composition in these cats. On the basis of these findings, we suggest that zoometric and bioelectrical impedance measurements may serve as practical, noninvasive, simple, and accurate methods for estimating body composition in domestic cats.

High sulfide concentrations in rumen fluid associated with nutritionally induced polioencephalomalacia in calves.

Nine 115- to 180-kg, hay-adapted, Holstein steers were fed an experimental diet with added sodium sulfate that induces polioencephalomalacia (PEM). Five calves developed the disease. Thiamine concentrations in blood, CSF, brain, and liver were not indicative of thiamine deficiency. The odor of hydrogen sulfide in eructated rumen gas was associated with the onset of PEM. Sulfide concentrations in rumen fluid were measured 1 or 2 times a week by 2 techniques. Sulfide concentrations progressively increased in all 9 calves after the feeding of the PEM-inducing diet commenced. The highest concentrations coincided with the onset of clinical signs of PEM and were significantly higher in the calves that developed PEM than in those that did not. This suggests that PEM can result from sulfide toxicosis following excess production of sulfide in the rumen.