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At least 649 records · Page 36Linked to original sources
PubMed2004

Cestrum diurnum leaf as a source of 1,25(OH)2 Vitamin D3 improves egg shell thickness.

A continuing concern of the poultry industry is the high incidence (12%) of egg losses in the laying house due to poor egg shell quality. Calcium (Ca) homeostasis is a key factor in egg shell formation. The economy of Ca utilisation is under the control of Vitamin D(3), particularly its active metabolite 1,25-dihydroxy cholecalciferol [1,25(OH)(2)D(3)]. Supplementation of 1,25(OH)(2)D(3) has been shown to increase specific gravity, shell thickness and shell weight of the egg. However, commercially available synthetic 1,25(OH)(2)D(3) is very expensive. Earlier studies from our Institute [Phytochemistry 37 (1994) 677] have identified a cheap, natural and rich source of 1,25(OH)(2)D(3) in the leaves of Cestrum diurnum (CD), a member of the Solanaceae family. In this study, CD leaves were explored as a source of 1,25(OH)(2)D(3) in the feed of layer birds to improve the egg shell thickness. Fifteen-week-old white leghorn layers were divided into four treatments of 60 birds each and as follows: (I) normal diet with Vitamin D(3), (II) normal diet with Vitamin D(3) + CD, (III) normal diet without Vitamin D(3) and, (IV) normal diet without Vitamin D(3) + CD powder. CD leaf powder was incorporated in to the feed at 0.3% level. The experimental feeding was continued up to 72 weeks of age of the birds. Weekly food intake and daily egg production were noted throughout the experimental period and the specific gravity of the eggs, feed consumed to lay one egg and egg shell thickness were determined. Incorporation of CD leaves in the feed had the maximal effect on all the parameters studied. The feed consumed to lay one egg was 20 g less than the control group. The specific gravity of the egg was higher by 0.005, than the control egg, indicating a 5% decrease in the breakage of eggs in CD fed chicks. Also there was a significant increase (P < 0.001) in egg shell thickness. The data suggest that incorporation of CD leaf powder in the feed of poultry layers increased the egg shell thickness, which in turn could decrease the economic loss due to breakage of eggs.

Animals↗
PubMed2006

Retention of different sizes of electronic identification boluses in the forestomachs of sheep.

Twelve types of electronic identification ruminal boluses of different dimensions were used to obtain a model for predicting their retention in the forestomachs of sheep. Boluses (n = 1,662) were made of ceramic materials, and their dimensions varied in o.d. (9 to 21 mm), length (37 to 68 mm), volume (2.5 to 21.0 mL), and specific gravity (0.85 to 3.91). Each bolus contained a half-duplex, standardized, glass-encapsulated transponder (32 x 3.8 mm). Boluses were administered to sheep (n = 1,497) of different ages by using the appropriate balling guns, and their retention under semiintensive conditions was recorded for at least 2 yr. When a bolus was lost, the sheep was rebolused with a heavier bolus. All sheep wore 2 plastic ear tags: one for the official control of health programs and the other for farm use. To determine the anatomical limit for a bolus passing through the gastrointestinal tract, the size of the reticulo-omasal orifice was measured in 46 adult sheep (male, n = 14; female, n = 32) that died by causes not related to bolus administration during the experiment. No signs of disease or growth alteration were detected in the bolused sheep. Total ear tag losses during the experiment period were 7.5% on average. Bolus retention (5 to 100%) varied according to bolus features and age of the sheep, but it showed a plateau after 18 mo. Inadequately dimensioned boluses were regurgitated or passed through the gastrointestinal tract and were excreted with the feces. The diameter of the reticulo-omasal orifice in adult sheep differed between male and female (23.1 and 21.8 mm, respectively; P < 0.01) and was greater than the o.d. of the retained boluses. Retention rate was predicted from bolus weight and volume by a logistic regression (R2 = 0.997; P < 0.001). When retention data from the literature (59.0 to 100%) were included in the model, the adjustment was slightly lower (R2 = 0.967). As a result, the minimum bolus weight estimated to reach a 99.5% retention rate in sheep varied between 16 and 45 g when volume varied between 3 and 22 mL, for boluses with a specific gravity between 2.0 and 5.2. In conclusion, bolus retention rate in sheep varied dramatically according to their features. For safe and efficient retention of electronic identification boluses in sheep, boluses of small volume and diameter (e.g., < 15 mm) with specific gravity and weight greater than 3.0 and 20 g, respectively, are recommended.

Animal Identification Systems↗
PubMed2005

Formation and instability of aerobic granules under high organic loading conditions.

The cultivation and instability of aerobic granular sludge in a sequencing batch reactor under high loading conditions were investigated. Compact bacteria-dominated aerobic granules with a mean diameter of 1 mm were formed at a chemical oxygen demand (COD) loading rate of 6.0 kg m(-3) d(-1) within 30 d. However, the compact bacteria-dominated aerobic granules were not stable and transited to large-sized filamentous ones gradually. With the formation of bacteria-dominated granules, the hydrophobicity and specific gravity of the sludge increased. When the granules were transited to filamentous ones, the hydrophobicity and specific gravity decreased. Both granules had a high COD removal efficiency, excellent settling ability and showed a clear, regular round-shaped outline. After the filamentous granules reached a diameter of 16 mm, due to the mass transfer limitation and the possible presence of anaerobes in the inner part of the granules, they began to disintegrate and be washed out of the reactor, follow by failure of the reactor.

Aerobiosis↗
PubMed1992

Method to measure the polymerization shrinkage of light-cured composites.

The polymerization shrinkage of light-cured dental composite resins has been reported to cause a marginal gap between the cavity wall and the restoration, leading to the premature and/or tensile stress failure of the composite restoration. This study measured the volumetric shrinkage of six light-cured posterior composites by measuring specific gravity differences between uncured and cured composite test specimens, using a modified version of ASTM method D792 "Specific Gravity and Density of Plastics by Displacement." The measured volumetric shrinkage ranged from 1.35% to 3.22%.

Bisphenol A-Glycidyl Methacrylate↗
PubMed1989

Sedimentation properties of chitosomal chitin synthetase from the wild-type strain and the 'slime' variant of Neurospora crassa.

Marked differences in the pattern of sedimentation of cellular structures were observed after isopycnic centrifugation of crude cell-free preparations from the Neurospora crassa wall-less 'slime' variant and mycelial wild-type strain. Kinetic studies of particle sedimentation showed that the various types of subcellular components, as revealed by turbidity, UV absorption, polypeptide patterns, and chitin synthetase activity determinations, sediment independently of one another. An important feature was the finding that chitin synthetase from 'slime' peaked at a median specific gravity of 1.1201 +/- 0.0036, whereas that from wild-type strain sedimented at a higher buoyant density (specific gravity 1.1349 +/- 0.0024). Different cultivation conditions or cell breakage procedures (osmotic lysis or ballistic disruption) did not seem to affect this sedimentation behavior. Electron microscopy revealed the presence of chitosomes (microvesicles containing chitin synthetase) in the chitin synthetase activity peaks obtained after isopycnic centrifugation of cell-free extracts from 'slime' and wild-type strains. The discrepancy in buoyant density of chitin synthetases from both N. crassa strains might point to inherent differences in chemical composition of the chitosomal microvesicles. In any case, the lower buoyant density of 'slime' chitosomes appears to be one of several major alterations in sedimentation behavior of subcellular structures. These alterations might be related to the inability of 'slime' to make a cell wall.

Centrifugation, Density Gradient↗
PubMed1978

[Experiences with hyperbaric bupivacaine solutions in spinal analgesia (author's transl)].

Spinalanaesthesia with hyperbaric bupivacaine (0.4%, 1.0%, 0.5%) was used in 713 patients having general surgical and urological operations. On average 19.30 +/- 1.55 mg bupivacaine was given and a spread of anaesthesia up to Th 7.21 +/- 1.55 achieved. Detailed evaluation of the 3rd group (0.5%) showed a latency period of 2.21 +/- 0.82 min and mean effective time of 4.33 +/- 0.75 h. The motor blockade was in 87% complete. The problem of the 0.5% solution with a specific gravity of 1.037 g/ml, which is in our opinion too high, was pointed out and a recommendation for a specific gravity of about 1.020 g/ml was given. Assuming proper positioning, spinal anesthesia with hyperbaric bupivacaine is a safe and simple anaesthetic method.

Anesthesia, Spinal↗
PubMed1991

Effect of an anion transport inhibitor, L-644,711, on brain injury and edema after temporary middle cerebral artery occlusion in rats.

The affect of L-644,711, an anion transport inhibitor, on ischemic brain injury and edema was investigated. Spontaneously hypertensive rats were given one of the following doses of intrathecal L-644,711 during 180 min of middle cerebral artery occlusion and 120 min of reperfusion: control, vehicle only; dose I, 100 microg/kg: dose II, 200 microg/kg; dose III, 250 mug/kg; or dose IV, 320 microg/kg. Immediately after the 5-h period of ischemia and reperfusion, the brains were analyzed for brain injury with 2,3,5-triphenyltetrazolium chloride, and for edema by microgravimetry (specific gravity). There were no between-group differences in specific gravity (brain water content). Brain injury (% of the hemisphere ipsilateral to middle cerebral artery occlusion) was less (p <0.05) in rats that received the 250 (35 +/- 5%, mean +/- SD) or 320 microg/kg (36 +/- 6%) doses of L-644,711 vs. the control group (47 +/- 5%). L-644,711 has been hypothesized to affect brain injury by improving the neuronal acid-base state, inhibiting astroglial swelling, decreasing neutrophil aggregation, or reducing glutamate release. The microgravimetric data do not support astroglial swelling as a primary mechanism of decreased brain injury.

Journal Article↗
PubMed1969

Heterogeneity of human platelets. I. Metabolic and kinetic evidence suggestive of young and old platelets.

Human platelets have been separated into two extreme density populations by centrifugation in specific density media. A large-heavy platelet population with specific gravity > 1.055 and a light-small population with specific gravity < 1.046 were obtained, each representing approximately 15-20% of the total population volume. The average volume per platelet of the separated large-heavy and light-small platelet populations was 12 and 5 mu(3) respectively. When data are expressed per milliliter platelets or per gram wet weight, the large-heavy platelet population had a 2-fold greater glycogen content, 1.3-fold greater orthophosphate content, 1.3-fold greater total adenine nucleotide content, 4.2-fold greater rate of glycogenolysis, 2.6-fold greater rate of glycolysis, 2.9-fold greater rate of protein synthesis, and 5.7-fold greater rate of glycogen synthesis. Significant differences were not obtained with respect to total lipid content or total lipid synthesis. The large-heavy platelet had a 2.5-fold greater resistance to osmotic shock as measured by adenosine triphosphate (ATP) or adenosine diphosphate (ADP) release. These data, as well as diisopropyl fluorophosphate (DFP(32)) survival curves in rabbits, indicate that large-heavy platelets have a greater metabolic potential and suggest that they may be the young platelets which progress with age to light-small platelets with a diminished metabolic potential.

Adenine Nucleotides↗
PubMed1984

Renal disease associated with colic in horses.

Renal dysfunction secondary to GI disorders may be relatively common in horses. Persistent dehydration of 8-10% of body weight can lead to prerenal azotemia, which may result in renal ischemia and renal disease if uncorrected. Dehydrated azotemic horses with a urine specific gravity less than 1.018 may have renal disease. Urine specific gravity readings greater than 1.025 usually indicate normal kidney function. A urine Na level less than 20 mEq/L and a urine/plasma creatinine ratio greater than or equal to 20:1 indicate prerenal problems. Use of nephrotoxic drugs should be avoided in septicemic or dehydrated horses. Salmonellosis and proximal enteritis often lead to renal complications. Renal disease associated with DIC warrants a poor prognosis. Treatment of acute renal failure is aimed at eliminating the underlying cause and correcting metabolic abnormalities. Use of IV fluids, dopamine, prostaglandin inhibitors, fresh and electrolyte-spiked water ad libitum, water-soluble vitamins and high-P diets is beneficial. Success of therapy should be judged by laboratory results rather than clinical impressions.

Acute Kidney Injury↗
PubMed1998

Influence of dietary osteolathyrogens on the eggshell quality of laying hens.

1. Laying hens were fed osteolathyrogens, either semicarbazide hydrochloride at 0.3 or 0.4 g/kg or beta-aminopropionitrile fumarate at 0.5 or 0.6 g/kg diet to examine their effects on eggshell quality. 2. Shell quality characteristics considered for evaluation were shell surface area, shell thickness, shell weight, percentage shell, shape index and the specific gravity of eggs. Measurement of shell quality traits revealed that the hens fed osteolathyrogens laid eggs with significantly lower specific gravities and proportion of shell by weight. These differences were not explained by differences in shell thickness or weight or the shape index of eggs. 3. It was concluded that osteolathyrogens cause hens to lay eggs with poor shell quality and such eggs are weak and fragile.

Aminopropionitrile↗
PubMed1992

Effect of duration of fasting on postmolt laying hen performance.

Two experiments were conducted to examine the effects of varying length of feed withdrawal on postmolt laying hen performance. Commercial laying hens (65 wk of age) were fed continuously or fasted for 4 or 10 days in Experiment 1 and fed continuously or fasted for 4, 7, or 14 days in Experiment 2. Egg production performance was evaluated for 35 wk of production following initiation of fasting. Hen-day egg production (Weeks 1 to 35) and egg weight (Weeks 5 to 35) did not differ between treatments in Experiment 1; however, in Experiment 2, egg production was depressed for the 14-day fasted hens compared with the fed hens. Lower egg weight also occurred for the 14-day fasted hens compared with the fed, 4-, or 7-day fasted hens in Experiment 2. Egg yield (grams of egg per hen per day) for Weeks 5 to 35 was lower for fed hens versus the 4- or 10-day fasted groups in Experiment 1, but no treatment differences occurred in Experiment 2. Feed efficiency (grams of egg per gram of feed) for Weeks 5 to 13 was not affected by length of fasting in Experiment 1, but feed efficiency of hens fasted for 14 days was lower (P less than .05) than that of hens on other treatments in Experiment 2. Egg specific gravity was highest for hens fasted for 10 or 14 days and was lowest for fed hens, with egg specific gravity for hens fasted for 4 or 7 days being intermediate (P less than or equal to .05). The results indicated that fasting periods of less than 10 days may yield satisfactory egg production and egg weight but that eggshell quality may be enhanced by using fasting periods of 10 days or longer.

Animals↗
PubMed1982

Reposital vasopressin response test in clinically normal dogs undergoing water diuresis: technique and results.

Maximal renal concentrating ability after parenteral administration of repositol antidiuretic hormone was evaluated in 13 clinically normal dogs undergoing water diuresis. Urine specific gravity and osmolarity progressively increased in all dogs and generally attained maximum concentrations after 8 to 12 hours. Urine specific gravity values increased from mean of 1.003 +/- 0.001 mOsm/kg of water to a mean maximal value of 1.042 +/- 0.009 mOsm/kg. Urine osmolarity increased from a mean of 132 mOsm/kg to a mean maximal value of 1,518 +/- 242 mOsm/kg. Water intoxication was observed in all dogs due to continued administration of water after antidiuretic hormone administration.

Animals↗
PubMed1994

Effects of diet acidity and protein level or source of calcium on the performance, gastrointestinal content measurements, bone measurements, and carcass composition of gilt and barrow weanling pigs.

A total of 228 crossbred weanling pigs (average age of 25 d and BW of 6.44 kg) were used in two trials to evaluate the responses to sex, diet acidity, protein level, and source of calcium on the performance, gastrointestinal digesta measurements, bone measurements, and carcass composition. Diet acidity was manipulated by varying the sources of supplemental phosphorus in the diets. Trial 1 (5 wk) was conducted as a 2 x 3 x 2 factorial to evaluate sex (gilts and barrows), diet acidity (pH 5.9 and .90% P, pH 6.1 and .63% P, and pH 6.9 and .63% P), and level of protein (16 and 22% CP). In Trial 2 (6 wk), diet acidity (pH 5.5, 5.9, and 6.8, all with .7% P) and Ca sources (CaCO3 and CaSO4) were used with gilts and barrows. The sex x diet acidity interactions were significant for ADG in both trials. Barrows seemed to respond to both the more acidic diets and the buffered phosphate diets even though the pH was less acidic than that of the unbuffered diets. Gilts responded only to the more acidic diets. In Trial 1, gilts ate more and grew faster (P < .05) than barrows, but no sex effects on performance were observed in Trial 2. Pigs fed 22% CP diets grew faster (P < .001) and more efficiently (P < .001) than did pigs fed 16% CP diets, but protein level x diet acidity and protein level x sex interactions were not significant. Stomach digesta DM, pH, and titration value were not consistently influenced by sex and diet acidity in Trials 1 and 2, by protein level in Trial 1, and by calcium source in Trial 2. Only the sex x diet acidity interaction for stomach DM tended to be significant in both trials; gilts fed the less acidic diets had the lowest DM, whereas barrows fed the more acidic diets had the lowest DM values. Although not significant in every case in both trials, bone (average of metacarpal and metatarsal) volume was lower and specific gravity and shear stress values were higher for gilts than for barrows. Pigs fed 16% CP diets had higher specific gravity (P < .05) and stress (P < .06) values than pigs fed 22% CP diets. A protein level x diet acidity interaction (P < .03) for stress suggested that pigs fed 22% CP diets were unaffected by diet acidity, whereas pigs fed 16% CP had the highest stress values when fed the more acidic diet and the lower P level.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Ultrasound speed in equine cortical bone: effects of orientation, density, porosity and temperature.

Ultrasound speed, as measured by a transmission technique in equine cortical bone, was found to vary markedly with the direction of the ultrasound path through the bone. Using bone samples from the mid-site of the third metacarpus of 20 horses, the ultrasound speed was measured as 4125 m s-1 in the longitudinal direction, 3442 m s-1 in the circumferential or transverse direction, and 3428 m s-1 in the radial direction. These results confirm the anisotropic properties of compact bone. Ultrasound speed had a positive linear relationship when compared with bone specific gravity of cortical bone (r = 0.773, n = 35, p less than 0.0001), and an inverse linear relationship with porosity. Specific gravity has an inverse correlation with porosity (r = 0.857, n = 35, p less than 0.0001). Over the temperature range of 4-42 degrees C, ultrasound speed varied inversely according to temperature with a logarithmic function giving the best fit. These results have important implications for the clinical applications of ultrasound speed in assessing bone quality in racehorses and provide important basic information for the understanding of the passage of ultrasound through cortical bone, which has possible clinical applications in humans.

Age Factors↗
PubMed1990

Glutamine synthetase inhibition prevents cerebral oedema during hyperammonemia.

The relationship between cerebral oedema and cerebral glutamine accumulation was investigated during acute hyperammonemia in anesthetized rats. Six hours of ammonium acetate infusion resulted in an increase in cortical glutamine concentration and a decrease in specific gravity. Pretreatment with methionine sulfoximine inhibited glutamine synthetase, prevented the increase in glutamine during hyperammonemia, and prevented the decrease in specific gravity. We conclude that the increase in brain water content is linked to the glutamine accumulation derived from the detoxification of ammonia by glutamine synthetase.

Acetates↗
PubMed1994

Tirilazad reduces brain edema after middle cerebral artery ligation in hypertensive rats.

Tirilazad (3 mg/kg i.v.) or vehicle was given 10 min, 3 and 12 hours after ligation of the right middle cerebral artery in male spontaneously hypertensive rats (n = 12 in each group). Brain specific gravity was determined in 23 predetermined cortical regions covering the core and penumbra areas 24 hours after the occlusion. The specific gravity was significantly higher in tirilazad-treated rats than in controls (p < 0.0001). When individual regions of the two groups were compared, the difference was significant in 9 of the 23 samples predominantly, but not exclusively, in the penumbra zone.

Animals↗
PubMed2002

Evaluation of a bladder tumor antigen test for the diagnosis of lower urinary tract malignancies in dogs.

OBJECTIVE: To evaluate the use of a human bladder tumor antigen test for diagnosis of lower urinary tract malignancies in dogs. SAMPLE POPULATION: Urine samples from dogs without urinary tract abnormalities (n = 18) and from dogs with lower urinary tract neoplasia (20) or nonmalignant urinary tract disease (16). PROCEDURE: Test results were compared among groups and among 3 observers. The effects of urine pH and specific gravity, degree of hematuria, and storage temperature and time of urine samples on test results were also assessed. RESULTS: Test sensitivity and specificity were 90 and 94.4%, respectively, for differentiating dogs with lower urinary tract neoplasia from dogs without abnormalities. However, specificity decreased to 35% for differentiating dogs with neoplasia from dogs with nonmalignant urinary tract disease. In dogs with neoplasia, results were significantly affected by degree of hematuria. However, addition of blood to urine from dogs without hematuria had no significant effect on test results. Although intraobserver variation was significant, urine pH, specific gravity, or storage time or temperature had no significant effect on results. CONCLUSIONS AND CLINICAL RELEVANCE: Although this bladder tumor antigen test was sensitive for differentiating dogs with malignancies of the lower urinary tract from dogs without urinary tract disease, it was not specific for differentiating dogs with neoplasia from dogs with other lower urinary tract abnormalities. It cannot, therefore, be recommended as a definitive diagnostic aid for the detection of lower urinary tract malignancies in dogs.

Animals↗
PubMed1979

Relationship between endotoxaemia and protein concentration of ascites in cirrhotic patients.

Endotoxaemia was investigated by the Limulus assay in 42 cirrhotic patients with ascites and in 33 without ascites. The incidence of endotoxaemia in the former group (59.5%) was significantly (P less than 0.05) higher than in the latter (36.4%). Correlation between endotoxaemia and specific gravity and concentrations of total protein, albumin, and globulin in ascitic fluid was studied in the group with ascites. The specific gravity of ascites in 25 patients with endotoxaemia was significantly greater than that in 17 patients without endotoxaemia (P less than 0.01). The concentration of total protein in patients with endotoxaemia (13.95 +/- 7.18 milligram, mean +/- SD) was nearly twice as high (P less than 0.01) as in patients without endotoxaemia (7.49 +/- 3.60 milligram). The protein content of those who showed reactions greater or equal to 2(+) in the Limulus assay (16.78 +/- 7.14 milligram) was a significantly (P less than 0.05) higher than in those with 1(+) reaction (11.26 +/- 6.33 milligram). Moreover, the concentration of albumin in patients with endotoxaemia (7.68 +/- 4.60 milligram) was more than twice that of the patients without endotoxaemia (3.39 +/- 1.58 milligram, P less than 0.01). On the other hand, globulin concentration in patients with endotoxaemia was 1.6 times that of patients without endotoxaemia (P less than 0.01). Similar differences were noted between endotoxaemic and non-endotoxaemic patients in the ascites-to-serum ratio in protein, albumin, and globulin. These results suggest that in liver cirrhosis endotoxaemia may cause an increase in protein concentrations in ascitic fluid, and that it may be a precipitating factor in the formation of ascites.

Adult↗