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Biomedical subjects

V Ravindran

Publications and source records attributed to V Ravindran.

41 records · Page 3Linked to original sources
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↗
PubMed1993

Effects of dietary lysine levels on performance and immune response of weanling pigs housed at two floor space allowances.

Three 35-d trials involving 288 crossbred weanling pigs (initial weight, 7.1 kg; age, 28 d) were used to determine the separate and interactive effects of two floor space allowances (.28 and .14 m2/pig) and three dietary lysine levels (NRC recommended, NRC+ .1% crystalline lysine-HCl, and NRC+ .2% crystalline lysine-HCl) on growth performance and several factors that measure variation within pens. Each trial was conducted as a 2 x 3 factorial arrangement of treatments in a randomized complete block design. There were four pens (four pigs per pen) for each of the six treatment combinations in each trial. The lysine x floor space allowance interaction was not significant (P = .25) for daily gain, daily feed intake, or gain/feed. Restriction of the floor space allowance decreased (P < .001) daily gain and daily feed intake, but gain/feed was not affected. The humoral immune response, as measured by the level of antibodies produced after two injections of ovalbumin, was not affected by floor space allowance. Addition of .1 and .2% crystalline lysine-HCl improved daily gain (P < .07), gain/feed (P < .10), and humoral immune response (P < .05) and was without effect (P = .28) on feed intake. Natural logarithms of variance, coefficients of variation, and range of daily gain and body weights were not changed by floor space allowance or dietary lysine level. Pigs on adequate and restricted floor space allowances responded similarly to dietary lysine levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1984

Effects of fiber and virginiamycin on nutrient absorption, nutrient retention and rate of passage in growing swine.

Three balance trials, each involving 12 crossbred gilts averaging 35.2 kg body weight, were conducted to determine the effects of dietary fiber and virginiamycin on nutrient digestibility, mineral absorption and retention, and digesta rate of passage (RP). Two levels of fiber (13.5 and 20.2% neutral detergent fiber) and two levels of virginiamycin (0 and 11 ppm) were used in a 2 X 2 factorial arrangement of treatments. All diets were isonitrogenous and isocaloric. The RP was determined by observing the time required for a change in feces color after the addition of .5% chromic oxide to the diet. The high fiber diet had a faster (P less than .01) RP, which was associated with depressions (P less than .001) in the digestibility of dry matter (DM), energy (E), cell contents, neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose (HC), cellulose, permanganate lignin and ash. Virginiamycin supplementation slowed (P less than .004) the RP of both low and high fiber diets, but improved (P less than .05) the DM, E, NDF, ADF, HC and cellulose digestibility of the high fiber diet only. Fiber increased (P less than .06) fecal N excretion, whereas virginiamycin supplementation decreased (P less than .08) fecal N excretion. The addition of virginiamycin improved the absorption and retention of P, Ca, Mg, Cu, Fe, Zn and Mn when added to the high fiber diet, but had little or no effect when added to the low fiber diet even though absorption and retention values for most minerals were similar or slightly higher for the unsupplemented high fiber diet compared with the unsupplemented low fiber diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗