Effect of dietary fluorine from Araxá rock phosphate on the hepatic production of cyclic-adenosine monophosphate in broilers

Abstract

The cyclic adenosine 3’, 5’-monophosphate (cAMP) production was evaluated in liver thin sections of broiler chicks fed on a experimental diet containing bicalcium phosphate or Araxá rock phosphate (ARP) as source of P, with a high content of fluorine, at different ages: from the first to the 42nd and from the 21st to the 42nd day of age. The intake of the ARP formulated diet starting from birth elicited an increase of cAMP production in broiler liver. However, when this diet was offered after the 21st day of age, the hepatic cAMP production in broilers was not significantly (P>0.05) affected, suggesting that the effect of high fluorine present in Araxá rock phosphate, on hepatic cAMP of broiler chicks depends on the age in which the experimental diet is started.

Bone histomorphometry of broilers submitted to different phosphorus sources in growing and finisher rations

“…In this sense, dicalcium phosphate is known as the best source in terms of phosphorus bioavailability and lesser fluorine concentrations, which is expected to determinate a better bone histological architecture (Fernandes et al, 1999;Rezende et al, 1999;Godoy & Chicco, 2000). (1) Means in the same column, followed by the same letter are not different at 5% of probability; PBA: percentage of bone by area; RA: ROI area; SRA: standard deviation of the ROI area; RP: ROI perimeter; SRP: standard deviation of the ROI perimeter; RE: ROI elongation; SRE: standard deviation of the ROI elongation; RAG: ROI angle; SRAG: standard deviation of ROI angle; E: entropy of RAG; L: lacunarity.…”

“…histomorphology at different degrees, depending on the fluorine content (Rezende et al, 1999) of the substitutive phosphorus source. Measurements applied to characterize bone images on this study can be used in other approaches of bones histologycal evaluation.…”

“…Normally, rock phosphate is not used, despite the great deposits of such materials found in this country. There are restrictions to the use of these rocks, once they possess high fluorine content, as demonstraded for Araxá rock phosphate (Rezende et al, 1999), and also because of scant information about its phosphorus absorption. However, there has been growing interest in evaluating the natural rock phosphate as an alternative low-cost phosphorus supply (Rezende et al, 1998;Veloso et al, 1998aVeloso et al, , 1998bFernandes et al, 1999;Godoy & Chicco, 2000;Rao & Reddy, 2001a, 2001b.…”