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PubMedDate not supplied

Phosphorus and ammonium concentrations in surface runoff from grasslands fertilized with broiler litter.

Application of broiler (Gallus gallus domesticus) litter to grasslands can increase ammonium (NH4-N) and dissolved reactive phosphorus (DRP) concentrations in surface runoff, but it is not known for how long after a broiler litter application that these concentrations remain elevated. This long-term study was conducted to measure NH4-N and DRP in surface runoff from grasslands fertilized with broiler litter. Six 0.75-ha, fescue (Festuca arundinacea Schreb.-)bermudagrass [Cynodon dactylon (L.) Pers.] paddocks received broiler litter applications in the spring and fall of 1995-1996 and only inorganic fertilizer N in the spring of 1997-1998. Surface runoff from each paddock was measured and analyzed for NH4-N and DRP. Broiler litter increased flow-weighted NH4-N and DRP concentrations from background values of 0.5 and 0.4 mg L(-1), respectively, to values > 18 mg L(-1) in a runoff event that took place immediately after the third application. Ammonium concentrations decreased rapidly after an application and were not strongly related to time after application or runoff volume. In contrast, DRP concentrations tended to decrease more slowly, reaching values near 1 mg L(-1) by 19 mo after the last application. Dissolved reactive P concentrations decreased linearly with the natural logarithm of days after application (p<0.03), and increased linearly with the natural logarithm of runoff volume (p<0.0001).

Animals↗

PubMedDate not supplied

Phosphorus losses from grasslands fertilized with broiler litter: EPIC simulations.

Broiler litter, a mixture of poultry excreta and bedding material, is commonly used to fertilize grasslands in the southeastern USA. Previous work has shown that under certain situations, application of broiler (Gallus gallus domesticus) litter to grasslands may lead to elevated levels of phosphorus (P) in surface runoff. The EPIC simulation model may be a useful tool to identify those situations. This work was conducted to evaluate EPIC's ability to simulate event and annual runoff volume and losses of dissolved reactive phosphorus (DRP) from tall fescue (Festuca arundinacea Schreb.)-bermudagrass [Cynodon dactylon (L.) Pers.] paddocks fertilized with broiler litter. The EPIC simulations of event runoff volume showed a trend toward underestimation, particularly for runoff events >30 mm. On an annual basis, EPIC also tended to underestimate runoff, especially at runoff volumes > 100 mm. Both event and annual runoff estimations were strongly associated with observed values, indicating that model calibration could improve the simulation of surface runoff volume. The relationship between simulated and observed values of DRP loss was relatively poor on an event basis (r=0.65), but was stronger (r=0.75) on an annual basis. In general, EPIC tended to underestimate annual DRP losses. This underestimation was apparently caused by the lack of an explicit mechanism to model broiler litter on the soil surface. These results suggested that additional work on the EPIC P submodel would be warranted to improve its simulation of surface application of broiler litter to grasslands.

Animals↗

PubMed1998

Cooking and palatability traits of beef longissimus steaks cooked with a belt grill or an open hearth electric broiler.

The objective of this experiment was to compare the effects of belt grill and Open Hearth electric broiler cookery on palatability and cooking traits of longissimus steaks. The longissimus thoracis from carcasses of grain-fed steers or heifers was used. Duplicate measurements were made for Warner-Bratzler shear force at 3 and at 14 d after slaughter (n = 180) and trained sensory evaluation at 14 d after slaughter (n = 91) using both cooking methods. Belt grill-cooked samples had lower (P<.01) percentage of cooking losses (21.5 vs 25.8%) and higher (P<.01) shear force values (4.6 vs 4.3 kg) than electric broiler-cooked samples. Repeatability of duplicate measurements was higher for cooking losses (.58 vs .23) and shear force values (.85 vs .64) for belt grill than for electric broiler cooked samples. Belt grilled steaks had lower (P<.01) cooking losses (20.2 vs 29.8%); higher (P<.01) tenderness (7.0 vs 6.7) and juiciness (6.0 vs 5.1); and lower (P<.02) connective tissue amount (7.7 vs 7.8), beef flavor intensity (5.0 vs 5.1), and off-flavor (3.2 vs 3.3) ratings than steaks cooked with the electric broiler. Belt grill cooking increased the repeatability of duplicate sensory measurements for tenderness (.87 vs .71), connective tissue amount (.66 vs .30), and juiciness (.51 vs .08) ratings, and cooking losses (.63 vs .18) compared with cooking with the electric broiler. Belt grill cooking increased the precision for measurements of cooking, Warner-Bratzler shear force, and palatability traits of beef longissimus thoracis.

Animals↗

PubMed2003

Erythropoiesis regulation during the development of ascites syndrome in broiler chickens: a possible role of corticosterone.

The ascites syndrome in broiler chickens is attributed to metabolic burdening, which results from intensive genetic selection for rapid growth coupled with exposure to extreme environmental conditions, such as low ambient temperature. These conditions impose on the broilers difficulties in fulfilling tissue demands for oxygen, and the birds exhibit a decrease in blood oxygen saturation and high hematocrit values. It is unknown whether the increase in hematocrit results from alteration in erythropoiesis or from fluid exudation out of the blood system to the abdominal cavity. The present study was conducted to examine the association between abnormal stress response and erythropoiesis process in ascitic broilers. Ascitic chickens revealed a uniquely continuous stress response: expressing an increase (P < or = 0.05) in plasma corticosterone concentration 2 to 3 wk before death. At 5 wk of age, ascitic broilers exhibited an increase (P < 0.05) in hematocrit, blood cell count, and packed cells and blood volumes, with no significant change in plasma volume. These results confirm an accelerated erythropoiesis process in ascitic birds. Increased blood cell production in ascitic birds was matched by an increase (P < 0.05) in the proportion of immature red blood cells (23%) in comparison with broilers that remained healthy (7%), and by decreased (P < 0.05) hemoglobin content relative to red blood cells. We conclude that continually increased corticosterone concentrations, as an inducer of erythropoiesis proliferation and differentiation arrest, in ascitic chickens, resulted in increased production of red blood cells (partially immature) with decreased hemoglobin content; this decrease in hemoglobin might have contributed to enhanced development of hypoxemia and to aggravation of the syndrome.

Animals↗

PubMed2003

Quantitative trait locus detection in commercial broiler lines using candidate regions.

A QTL that explained a large proportion of the phenotypic difference between broiler and layer chickens in an experimental cross was evaluated in a commercial broiler line. A three-generation design, consisting of 15 grandsires, 608 half-sib hens, and more than 50,000 third-generation offspring, was implemented within the existing breeding scheme of a broiler breeding company. Four markers from a candidate region on chicken chromosome 4 were selected for their informativeness in the grandsires and used to genotype the first two generations. Using half-sib analyses, linkage was studied between these markers and 13 growth and carcass traits. The QTL analyses confirmed the presence of significant QTL for body weight (P < 0.01) and residual feed intake (P < 0.05) on chicken chromosome 4. Furthermore, evidence was found for QTL affecting the relative weight of bone and muscle in the thigh. Four more markers were added to increase resolution of the QTL positions. This increased the significance of the QTL for body weight (P < 0.001) and residual feed intake (P < 0.01) and showed evidence (P < 0.05) for additional QTL affecting carcass weight and conformation score. This study showed for the first time that a QTL that explains differences between broilers and layers was segregating in lines that have been selected for body weight over 50 generations. A possible explanation could be a pleiotropic or closely linked effect on fitness-related traits that are not part of the present study. The results demonstrate the feasibility of QTL detection and the potential for marker-assisted selection within a commercial broiler line without altering the existing breeding scheme.

Animals↗

PubMed1981

Effects of dietary zearalenone on finishing broiler chickens and young turkey poults.

A total of 168 broiler chickens (6 to 9 weeks of age) and 192 turkey poults (3-1/2 to 6-1/2 weeks of age) were fed purified zearalenone at levels of 0 (control), 10, 25 (turkeys only), 50, 100, 200, 400, and 800 mg/kg diet for a 3 week period to evaluate its toxicity. Dietary zearalenone had no effect on body weight gain, feed consumption, weights of liver, heart, spleen, and bursa of Fabricius, serum calcium, phosphorus, alkaline phosphatase, total protein and cholesterol, hematocrit, hemoglobin, red blood cell count, white blood cell count, and differential leukocyte count in both chickens and turkeys. Male broiler comb and testes weights were reduced by high levels of zearalenone. Female comb weight, broiler oviduct weight, and turkey testes and ovaries were unaffected by zearalenone. Histopathological examination of tissues revealed no change due to zearalenone. Male turkeys fed 400 and 800 mg/kg zearalenone had increased development of dewlaps and caruncles and exhibited considerable strutting behavior. Muscle and fat tissue from broilers fed 800 mg/kg zearalenone had no detectable estrogenic activity as measured by mouse uterine bioassay. These studies indicate that the effects of dietary zearalenone on finishing broilers and young growing turkey poults are minimal.

Animals↗

PubMed1981

Gaseous metabolism of leghorns and broilers during early growth: existence energy rate.

Existence energy rate (EER) was measured on male Ross x Arbor Acre broilers and DeKalb 231 x Cornell White Leghorns from day of hatch to 8 weeks of age. The EER was measured in an open circuit respirometer with feed and water available ad libitum. The log of heat production (kilocalories per bird per day) was plotted against the log for body weight (kilograms) for each type bird. Data from broilers and Leghorns were then compared using analysis of covariance. The equations best describing EER for Ross x Arbor Acre broilers and DeKalb 231 x Cornell White Leghorns were Y = 148W.77 and Y = 110W.74, respectively, where Y equals kcal/bird-day and W equals body weight (kg). There was no significant difference in slope (.77 compared to .74) between the two types of poultry; however, broilers had a significantly higher EER than Leghorns (147 compared to 110) when analyzed at equal body weights. Apparently the greater food intake and activity associated with feeding effected the marked increase in heat production by broilers.

Animals↗

PubMed1985

The tolerance of White Leghorn and broiler chicks, and turkey poults to diets that contained deoxynivalenol (vomitoxin)-contaminated wheat.

Three experiments were done to determine the effects of giving White Leghorn chickens, broiler chickens, and turkey poults diets that contained white winter or spring wheat contaminated with 4-deoxynivalenol (DON). Diets that contained .35 and .7 mg DON/kg from winter wheat did not (P greater than .05) influence feed intake, body weight gain, feed/gain ratio, and organ weight/body weight ratios of Leghorn and broiler chickens, and poults when fed between 7 and 21 days in Experiment 1. Dietary DON levels up to 4.6 mg/kg increased the feed intakes (P less than .01) and daily body weight gains (P less than .05) of Leghorn chickens between 7 and 35 days of age in Experiment 2 but had little effect (P greater than .05) on these variables for broiler chickens between 7 and 52 days of age in Experiment 3. Within Experiments 2 and 3, feed/gain ratios and organ weight/body weight ratios were similar among the Leghorn and broiler chickens, respectively. The dressing percent and chilled carcass weights of eviscerated broiler chickens were not affected (P greater than .05) by DON in the diets of Experiment 3. Mortality was low (less than 3.3%) for the three experiments and necropsy examination indicated that the birds died from several causes unrelated to the dietary treatment. There was no evidence of emesis during the experiments or of overt changes in the appearance of the oral cavity, heart, liver, spleen, kidney, proventriculus, gizzard, and intestines of a random sample of birds killed by carbon dioxide asphyxiation and necropsied. Differences occurred between the analyzed and calculated DON contents of the experimental diets; possible reasons for these differences are discussed. The results of these experiments indicate that young chickens and turkey poults can tolerate diets that contain DON up to at least 5 mg/kg from white winter or spring wheat.

Animal Feed↗

PubMed1985

Water consumption of broiler chickens under commercial conditions.

The daily water consumption of twenty-four flocks of commercial broiler chickens was measured (average = 19,757 birds/flock). Broilers were raised in two houses--a conventional, open, automatic side-curtained house and a totally enclosed, power-ventilated house on the same premises. Commercially available strains were used and various feed additives were compared during the trials. Water:feed consumption ratios averaged 1.77 g/g. Water consumption was a linear function of broiler age (R2 greater than .99). It could be predicted by multiplying 5.28 g times the broiler's age (5.1 g for birds slaughtered in the cooler times of the year or 5.7 for those slaughtered in the warmest months). Housing type had no effect on water consumption. Increasing dietary sodium increased water consumption, although its effect could not be clearly discerned statistically from that of female parent genotype. It is suggested that 5.28 ml/bird/day of age is a good method of predicting the water consumption of broiler chickens.

Age Factors↗

PubMed1985

Energy utilization by the broiler chicken as affected by various fats and fat levels.

Two experiments were designed to investigate the effects of fat supplementation at different levels on energy utilization by the broiler chicken. In one experiment, finisher diets containing 2.5, 5.0, or 10.0% of added corn oil (CO), poultry oil (PO), tallow (T), or a commercial hydrolyzed animal-vegetable fat blend (HB) were fed. In the second experiment, starter diets containing 0, 2.5, or 7.5% added CO, PO or HB were fed. Metabolizable energy (ME) values were not controlled through formulation but were determined experimentally. Energy retention was measured by a slaughter technique, and metabolic energy losses were calculated as the difference between metabolizable energy intake and energy deposition in the carcass. Broilers that were fed PO, T, and HB failed to adjust feed intake to control caloric intake. They ate significantly more ME calories per day when these fat sources were fed, gained more, were fatter, and had a lower feed:gain ratio than broilers fed no added fat or lower levels of fat. Failure to regulate caloric intake when fats are added to diets may be a component of the "extra caloric" effect of fat. Broilers which were fed CO tended to regulate their caloric intake better than those which are fed PO, T, and HB. It was not determined if CO is less palatable than the other fat sources or if the unsaturated fatty acids metabolically regulate appetite. When CO was fed, broilers tended to have lower feed:gain ratios than when the other fats were fed. There was an indication that daily heat production was less when CO was fed, which would suggest a lower heat increment. Fatty acid analysis verified the efficient use of dietary fats for adipose deposition and suggested a disproportionately greater use of the unsaturated fatty acids for carcass lipids.

Animal Feed↗

PubMed1986

Individual and combined effects of aflatoxin and deoxynivalenol (DON, vomitoxin) in broiler chickens.

The individual and combined effects of aflatoxin and deoxynivalenol (DON) were evaluated in young broiler chickens (Hubbard X Hubbard). The experimental design was a 2 X 2 factorial with treatments of 0 and 2.5 micrograms of aflatoxin/g of feed (ppm) and 0 and 16 micrograms of DON/g of feed. The broilers were maintained on these dietary treatments from hatching to 3 weeks of age in electrically heated batteries with feed and water available ad libitum. The aflatoxin treatment significantly (P less than .05) decreased body weight; weight gain; increased the relative weight of the spleen, liver, and kidney; induced hepatic hyperlipemia; decreased activity of lactic dehydrogenase; and decreased serum levels of protein, albumin, and phosphorus. The toxicity of DON was expressed through reduced growth rate, increased feed conversion; increased relative weight of the gizzard, anemia, decreased activity of lactic dehydrogenase, and decreased serum triglycerides. The interaction between aflatoxin and DON was characterized by reduced growth rates; increased feed conversion, increased relative weight of the proventriculus, gizzard, spleen, liver, and kidney, anemia, hepatic hyperlipemia, decreased activity of alkaline phosphatase, glutamic oxalacetic transaminase, and lactic dehydrogenase, and decreased serum levels of protein, albumin, uric acid, cholesterol, triglycerides, and calcium. These data demonstrate that both aflatoxin and DON can limit broiler performance and adversely effect broiler health. The effects of the combination of aflatoxin and DON on broiler performance and health was more severe than the individual effects of these mycotoxins; however, the interaction was not severe enough to represent toxic synergy and can best be characterized as additive toxicity.

Aflatoxins↗

PubMed1987

Rate of passage of corn-canola meal and corn-soybean meal diets through the gastrointestinal tract of broiler and White Leghorn chickens.

The effect of corn-canola meal and corn-soybean meal diets on the form and function of the gastrointestinal tract of broiler (meat-type) and White Leghorn (egg-type) cockerels was measured from 14 to 44 and 14 to 86 days of age or 203 to 1,844 and 115 to 1,777 g of body weight, respectively. Dry weights of the empty crop (P less than .01), gizzard (P less than .001), and ceca (P less than .001) relative to live body weight (g/kg) were lighter in broilers than in Leghorns. Canola meal at 370 g/kg diet was associated with increased (P less than .001) dry weight of the gizzard and jejunum relative to body weight. Soybean meal at 370 g/kg diet was associated with increased (P less than .001) dry weight of the ceca relative to body weight. The lengths, relative to a power of body weight of the duodenum (cm/g.187) and jejunum plus ileum (cm/g.240), were longer (P less than .001) in broilers than in Leghorns. The canola meal diet was associated with an increase (P less than .001) in length of the jejunum plus ileum (cm/g.240) relative to a power of body weight. Mean retention time (MRT) of a particle marker, 103ruthenium phenanthroline, increased with body weight in the entire gastrointestinal tract (P less than .001) and in each of its segments except in the proventriculus, where it was not affected by body weight (P greater than .05), and in the gizzard, where it decreased (P less than .05) with body weight. The MRT, adjusted for body weight in the entire gastrointestinal tract of broilers (338.0 +/- 10.8 min) and Leghorns (359.9 +/- 10.8 min), was similar (P greater than .05) but varied significantly in segments of the gut for both type of chicken and diet. Adjusted MRT was shorter in the crop (P less than .001) and gizzard (P less than .001) and longer in the duodenum (P less than .001) and ileum (P less than .01) of broilers than Leghorns. The soybean meal diet was retained for 2.3 min longer in the duodenum (P less than .001) and 84.2 min longer in the ceca (P less than .001) than the canola meal diet, which accounted for the longer (P less than .001) retention of the soybean meal diet in the entire gastrointestinal tract (388.0 +/- 10.6 vs. 309.8 +/- 10.8 min). Segments of the gastrointestinal tract vary in length, weight, and MRT of digesta with dietary composition and type and body weight of chicken.

Animal Feed↗

PubMed1988

Age-constant versus weight-constant feed consumption and efficiency in broiler chickens.

Weekly body weights, feed consumption (FC), and feed efficiencies (FE = gain:feed) of 148 male and 125 female broilers were measured individually between 2 and 7 wk of age. Multiple regression analyses of these traits were performed to examine the influence of body weight, weight gain or feed consumption, age, and individual broiler differences. Four different measures of FC and FE from 4 to 6 wk of age were compared within sex: age-constant FC and FE; weight-constant FC and FE; age-constant-weight-corrected FC and FE; and weight-corrected FC and FE, which estimate weight-constant measures. Much of the variation (85 to 90%) among broilers in FC and FE was due to age and body weight differences. Partial regression coefficients indicated that increased body weight at commencement of testing was associated with increased FC and reduced weight gain and FE. Correlations between age-constant and weight-constant FC were zero. This indicates the two forms have little in common. Correlations of body weights and weight gain with FC were negative (-.5 to -.8) for weight-constant values but positive (.5 to .8) for age-constant values. Hence, correlations of the correct (weight-constant) measure of FC with body weights indicate that faster growth gives rise to lower broiler feed consumption. Age-constant and weight-constant FE values were positively correlated (.8 to .9); however, the latter values had larger correlations with body weights and weight gain. These results emphasize the need to correct age-constant FC and FE for body weight differences in order to evaluate differences in efficiency among broilers more accurately.

Age Factors↗

PubMed1988

Effect of feed restriction on feed efficiency and incidence of sudden death syndrome in broiler chickens.

An experiment was conducted to determine the effect of feed restriction on the incidence of sudden death syndrome (SDS). Body weight, feed efficiency, and incidence of SDS were compared for broilers fed ad libitum and broilers restricted in feed intake by 25%. Six pens of 50 male broilers were fed commercial-type texture diets ad libitum, and six pens of birds were restricted to 75% of this intake from 5 to 39 days of age. Growth rate and the incidence of SDS were significantly higher in ad libitum-fed broilers. Feed efficiency was better in the ad libitum-fed group up to 11 days of age and then became similar to that of the restricted group. Results support the hypothesis that the incidence of SDS is related to growth rate and suggest that SDS mortality may be reduced by growing broilers at a slower rate.

Animal Nutritional Physiological Phenomena↗

PubMed1988

Progression of ochratoxicosis in broiler chickens.

The progression of effects induced by administration of ochratoxin A were characterized in young male broiler chickens (Hubbard x Hubbard). The experimental design consisted of four dietary treatments of ochratoxin A (0, 1.0, 2.0, and 4.0 micrograms ochratoxin A/g feed) and 11 replicates of 10 broilers/replicate. Broilers were housed in electrically heated batteries with feed and water available ad libitum. Broilers were weighed, bled, killed by cervical dislocation, and necropsied at 3, 6, 9, 12, 15, 18, and 21 days of age. Toxicity of ochratoxin A to broilers was evident as early as 6 days of age, when significant (P less than .05) growth depression occurred at 4.0 micrograms dietary ochratoxin A/g feed. Dietary ochratoxin A significantly increased the relative weights of the liver, kidney, spleen, pancreas, and gizzard. Anemia, characterized by a significant decrease in packed-cell volume and hemoglobin levels, was present during ochratoxicosis. Hepatotoxicity of dietary ochratoxin A was evident through an observed significant reduction in serum levels of total protein, albumin, globulin, cholesterol, triglyceride, and blood urea nitrogen, and a significant increase in the serum activities of gamma glutamyl transferase and cholinesterase. A significant increase in serum uric acid and creatinine levels was indicative of nephrotoxicity. These data provide a description of the progression of ochratoxicosis in broilers that should be useful in diagnosis and in improved understanding of ochratoxicosis.

Animals↗

PubMed1988

Incidence and level of Campylobacter jejuni in broiler processing.

The distribution and level of Campylobacter jejuni throughout broiler processing was evaluated. Six trials were conducted at three broiler processing plants to determine the occurrence of C. jejuni on commercial broilers as affected by specific processing functions. Counts were determined at specific sampling stations throughout the plants, and patterns of counts among sampling stations and plants were observed. Between 1,100 and 5,500 C. jejuni/1,000 cm2 skin surface (represents half the skin surface area of one defeathered broiler) were found on birds entering the three plants. Increases in C. jejuni levels were associated with both the picking and evisceration operations. Broiler carcasses ready for packaging contained approximately 50 organisms/1,000 cm2. Campylobacter jejuni was also recovered from gizzard samples, carcass and gizzard chill water, and swab samples taken of selected equipment surfaces.

Animals↗

PubMed1990

Impact of L-phenylalanine supplementation on the performance of three-week-old broilers fed diets containing ochratoxin A. 2. Effects on hematology and clinical chemistry.

Phenylalanine was evaluated for its ability to protect broiler chickens from the toxic effects of ochratoxin A (OA). A completely randomized 2-by-3 factorial design was utilized consisting of 0, .8, and 2.4% supplemental L-phenylalanine (Phe) and of 0 and 4 mg of OA per kg of diet. The basal diet contained 14% protein. Broilers were raised in battery brooders to 3 wk of age, when blood was collected and various hematological parameters were determined. The health status of the broilers was evaluated by assaying serum for various enzyme activities and metabolites using an automated, clinical chemistry analyzer. Adding OA to the broiler diets resulted in an increased concentration of serum hemoglobin as well as increased activity for cholinesterase and gamma glutamyl transferase but in decreased activity for aspartate amino transferase, lactate dehydrogenase, and alkaline-phosphatase activity as well as decreased concentrations of total triglyceride and of inorganic phosphorus. Supplemental Phe decreased the concentrations of hemoglobin and serum glucose. The regression slopes for Phe at 4 mg of OA per kg of diet were significant for uric acid, creatinine, total protein, albumin, and cholesterol suggesting that supplemental Phe improved the health status of the broilers fed diets containing OA with respect to these parameters.

Alkaline Phosphatase↗

PubMed1990

Ascites in growing broilers: a research model.

A method was developed to experimentally produce ascites in broiler chickens. High-altitude simulation (treatment group) was conducted to study the development of ascites in broiler chickens. In each of three experiments, 15 male broiler chicks (1 wk old) were placed in a hypobaric chamber (principal groups) for 5 wk and 15 other chicks were reared in batteries (control groups). Ascites occurred among chicks in the principal groups recorded at 13, 27, and 80% at simulated altitudes of 1,980, 2,438, and 2,896 m, respectively. No ascites were observed in the controls at 100 m (the altitude at College Station, Texas). Body weight was significantly (P less than .05) reduced for broilers in the principal groups versus the controls-especially at 2,896 m, where the principals weighed 500 g less than the controls. The counts for hematocrit, hemoglobin, and red blood cells were significantly (P less than .05) increased in all treatment groups; while at 2,438 and 2,896 m, corticosterone was significantly reduced. Histopathology indicated consistent, mild, cardiopulmonary lesions similar to those observed in the spontaneous ascites of broiler chickens. The high-altitude simulation model will be useful in studying the etiological factors and interactions causing ascites.

Altitude↗