The following physico-chemical characteristics of various calcium sources, differing in origin and particle size were determined: mineral composition, sieve and image analysis, apparent solubility (AS), surface area (SA), porous volume, specific gravity, and compressibility (C). The AS, SA, and C values were related more to the calcium particle size than to its origin and were higher in ground calcium sources. Calcium retention of seashells treated with phosphoric acid, oyster shells, and limestone using two particle sizes, ground or particulate, was assayed in 98 broiler chicks. Particulate marble was also tested in this experiment. Calcium retention expressed as a percentage of calcium ingestion was decreased when coarse particles of calcium were supplied in lieu of pulverized sources (40 versus 49%). An experiment with a 3 x 3 x 3 factorial arrangement of treatments were tested using 576 broiler chicks. Treatments included three calcium sources (phosphorus-treated shell, oyster shell, and marble), three particle sizes [ground (less than .15 mm), medium (.6 to 1.18 mm) and coarse (greater than 1.18 mm)] and three levels of calcium (.5,.7, and .9%) with ground limestone as a reference. Performance, tibial morphometry, breaking strength variables, and ash content were measured at 4 wk of age. Weight gain and feed conversion were ameliorated with ground particles of calcium. Cortical thickness, length of the tibia, stiffness, stress, and tibia ash were diminished when coarse particles of calcium were incorporated in the diets. Conversely, the origin of the calcium source hardly affected these criteria. Additionally, the incorporation of phosphorus-treated shells was assayed in 112 broiler chicks. Coarse particles decreased calcium retention. Consequently, ultimate stress, the modulus of elasticity, and stress were impaired. It is concluded that differences in utilization of calcium carbonate sources by the broiler chick is primarily a result of particle size rather than origin. Ground particles of calcium (pan to .15 mm) significantly improves performance and tibial ossification characteristics in broiler chicks.
In chicks, immature pullets and laying hens, the inhibition of gastric acid secretion by omeprazole, an H+,K+-transporting ATPase (EC 3.6.1.36) inhibitor, greatly increased proventricular and gizzard pH values. Consequently, gizzard soluble Ca concentration deceased and the insoluble Ca fraction increased. Inhibition of acid secretion increased duodenal pH values in immature pullets and laying hens but not in chicks. Duodenal soluble and ionic Ca concentrations were lowered by gastric acid inhibition in chicks and to a larger extent in immature pullets and laying hens. The use of Ca of coarse particle size increased the gizzard insoluble Ca fraction in chicks and pullets. However, it did not influence its soluble Ca fraction in chicks but tended to reinforce the negative effect of omeprazole on soluble Ca in the gizzard and duodenum of chicks and laying hens. Coarse particles of Ca led to an increase in gizzard and duodenal soluble Ca at the end of eggshell calcification in laying hens. An enhancement in the level of Ca in the diet from 10 to 36 g/kg increased gizzard soluble Ca and duodenal soluble and ionic Ca concentrations in immature and adult hens. Intestinal Ca retention and bone mineralization was unaffected by gastric acid inhibition in chicks but were largely diminished by the use of coarse particles of Ca. Gastric acid inhibition was associated in laying hens with decreased Ca retention to a small extent and with reduced eggshell quality. These observations confirm that gastric acid secretion is of importance for CaCO, solubilization but question its role as a prerequisite for intestinal Ca retention in chicks and even in hens fed on a high Ca diet.
-Thirty-two pigs, weaned at 28 days of age with an average body weight of 9 kg, were used in an experiment devoted to the assessment of the bioavailability of an organic Zn source (ZnOrg) compared to Zn sulfate. Pigs were fed a basal diet containing 28 mg·kg -1 of Zn supplemented with ZnSO 4 or ZnOrg to provide 0, 10, 20 and 30 mg·kg -1 of supplemental Zn. In order to reduce the amount and the variability of their Zn stores, pigs were fed the basal diet for a 7-day adjustment period preceding a 19-day experimental period. Growth performance and bone bending moment were not affected by the level nor the source of zinc. On the contrary, plasma zinc concentration and alkaline phosphatase activity (P < 0.001), bone zinc concentration (P < 0.001), liver and empty body zinc concentrations (P < 0.01) as well as the amount of Zn retained estimated both by the balance technique (BT) (P < 0.001) and by the comparative slaughter technique (CST) (P < 0.01) increased linearly in response to supplemental Zn. However, the two Zn sources exhibited a similar bioavailability. Twenty-seven percent of Zn intake was retained when measured by means of the balance technique, regardless of the dietary level or zinc source. Zn retention was 54% lower when measured by means of the CST as compared to the BT. (0)2 23 48 50 80; e-mail: jondreville@st-gilles.rennes.inra.fr de croissance et le moment de flexion de l'os n'ont été affectés ni par le niveau ni par la source de zinc supplémentaire. Au contraire, la teneur en zinc et l'activité de la phosphatase alcaline du plasma (P < 0,001), les teneurs en zinc osseuse (P < 0,001), hépatique et corporelle (P < 0,01) ainsi que la quantité de zinc retenu estimée par la technique du bilan (P < 0,001) et celle des abattages comparés (P < 0,01) augmentaient linéairement avec l'addition du zinc. Cependant, aucune différence entre les sources n'a été détectée. Le coefficient de rétention de zinc, estimé par la technique du bilan, était de 27 % en moyenne, indépendamment du niveau ou de la source de zinc supplémentaire. Estimée par la technique des abattages comparés, la rétention de Zn était de 54 % inférieure à la valeur obtenue selon la technique du bilan.porc / zinc / biodisponibilité / source / indicateur
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.