Estudos histológico-morfométricos e microrradiográficos de costelas de bovinos suplementados com fosfato de rocha

Abstract

Pesq. Vet. Bras. 17(3/4):96-104, jul./dez. 1997 96 SINOPSE.-O objetivo do presente trabalho foi o de avaliar, através de técnicas especializadas, as possíveis alterações ós-seas produzidas em bovinos em decorrência da ingestão prolongada de diferentes níveis de flúor contido no fosfato de rocha de Tapira utilizado como fonte suplementar de fósforo. No primeiro experimento bovinos confinados ingeriram, durante 6 meses, quantidades variáveis (63 e 128g/dia) de fosfato de Tapira contendo 1.3% de flúor. No segundo experimento, bovinos em pastos de Brachiaria decumbens ingeriram, durante 33 meses, misturas minerais contendo diferentes níveis de fosfato de rocha de Tapira. No terceiro experimento, novilhas com idade inicial média de 14 meses ingeriram mistura mineral com fosfato de Tapira até a quinta lactação inclusivamente. Através de exames histológicos, morfométricos e microrradiográficos das amostras de costelas, não se observaram alterações da normalidade óssea, bem como não foram registradas diferenças entre amostras provenientes de diferentes tratamentos. Tais achados permitem inferir que, do ponto de vista de alterações ósseas, o fosfato de rocha de Tapira pode ser utilizado como fonte suplementar de fósforo para bovinos, nas dosagens, períodos e manejos alimentares estudados, sem risco de produzir alterações patológicas nos esqueleto dos animais. The present study was conducted to evaluate possible bone changes in cattle due to the ingestion of different levels of fluorine from rock phosphate used as a phophorus supplement. The bone material studied were ribs collected from cattle of three experiments where Tapira rock phosphate was used at different levels and during different periods as a partial or sole source of supplementary phosphorus. In the first experiment feedlot cattle ingested during a 6 month period 63 and 128g/day of Tapira rock phosphate containing 1.3% fluorine. In the second experiment cattle maintained in Brachiaria decumbens pastures during 33 months ingested several levels of Tapira rock phosphate in the mineral mixtures. In the third experiment heifers averaging 14 months of age ingested a mineral supplement with Tapira rock phosphate until the 5th lactation period. Careful examination of the rib samples by histological, morphometric and microradiographic techniques revealed no abnormalities which could be related to fluorine ingestion, neither any differences among tretaments regarding the bone structure. These findings support the conclusion that, as far as bone alterations are concerned, Tapira rock phosphate could be used as a source of phosphorus for cattle under the conditions described in the experiments, a practice which would markedly reduce the cost of phosphorus supplementation.INDEX TERMS: Fluorine, phosphorus supplementation, rock phosphate, bone alterations, cattle.

Blood and bone parameters of cattle fed diets containing different phosphates and phosphorus: fluorine relations

“…The bones of the animals that consumed the CONT diet presented lower (P<0.05) relation Havers area/Osteon area in comparison with that animals that ingested DC30. Pilati et al (1997) do not observed histological abnormalities in the bovine bones, suggesting the utilization of rock phosphate to bovine nutrition. ., Salvador, v.16, n.1, p.93-105 jan./mar., 2015 http://www.rbspa.ufba.br ISSN 1519 9940 http://dx.doi.org/10.1590/S1519-99402015000100011…”

“…Humberto (2007), evaluating phosphorus and fluorine sources to sheep, identified that the fluorine deposition in ribs was ten times lower in the animals fed with dicalcium phosphate in relation to the ones fed with rock phosphate and sodium fluoride, being that the deposition of fluorine was higher when the fluorine was originated of the sodium fluoride. In laboratory animals treated with sodium fluoride, in a chronic way, it was related subnormal growth and significant decrease in the body weight when compared with the control animals (PUSHPALATHA et al, 2005). Filappi et al (2008) working with ovines treated with sodium fluoride, concluded that the chronic administration of fluorine induced to the accumulation of this element in the bones, even with high calcium level in the alimentation.…”