Estudos histomorfométrico e histológico das lesões ósseas causadas por flúor em aves

Abstract

Sodium fluoride was administered in the water to 2 groups of 25 Shaver female poultry. Group A received fluoride from 1 to 120 days of age and group B from 61 to 120 days. Each group was divided into 5 treatments, with 5 chickens each, which received 0, 25, 50, 200, and 400 ppm of fluoride in the water, respectively. All animals were killed at 120 days of age. For histomorphometric studies the left femur and tibia were used, and for histologic studies the right femur and tibia. In the cortical bone, cortical porosity was slightly increased by fluoride, but the differences with the control group were not significant. Cortical thickness increased in the animals treated with fluoride (p<0,05, r 2 = 0,59 ). In the trabecular bone, of group A, trabecular thickness (TT) (p<0,05, r 2 = 0,63) and trabecular bone volume (TBV) (p<0,05, r 2 = 0,72) increased in treatments receiving 25-200 ppm, and decreased in the 400 ppm treatment, as it was demonstrated by quadratic regression analysis. In group B there was a positive linear correlation on TT (p<0,05, r 2 = 0,98) and TBV (p<0,05, r 2 = 0,77) with fluoride ingestion.The osteoid surface was also positively correlated with the amount of fluoride ingested by the animals (p<0,001, r 2 = 0,80). These results suggest that fluoride improves osteoblastic function resulting in increased osteoid production and bone apposition. In the other hand, in the animals treated with 400 ppm of fluoride for 120 days bone apposition was reduced suggesting a functional alteration of the osteoblasts or improved bone resorption. In the histological study of bone tissue all animals that received fluoride showed an increased trabecular thickness which was more marked in the 200-400 ppm treatments. In chickens treated with 200-400 ppm of fluoride osteoblasts and osteoclasts were more numerous suggesting an increased bone turnover. In cortical bone Haversian canals were narrowed on the periosteal surfaces and resorption spaces were enlarged on the endosteal surfaces.INDEX TERMS: Fluoride, bone, bone histomorphometry, poultry, fluorosis.

Bone densitometry and calcium serum levels in chickens treated with filtered or unfiltered water

“…Fluoride levels were below the maximum allowed levels, favoring bone physiology, because, according to Raffi et al (1997), excessive amounts of fluoride can cause bone weakness in poultry. Similarly, manganese levels (Table 4) were below allowed limit for drinking water (0.5 mg/L) established by Palhares (2005).…”

Histomorfometria do tecido ósseo em ratas castradas tratadas com tibolona

“…A objetiva escolhida permitiu que se contasse o número de pontos coincidentes com cada estrutura analisada e, a partir daí, fosse calculado o percentual ocupado por cada estrutura epifisária no corte histológico. A medição da porosidade e da densidade trabecular óssea seguiu metodologia adaptada (30,37) , de acordo com as fórmulas a seguir: Ao analisarmos a espessura cortical e a área da cavidade medular nas diáfises das tíbias, não encontramos diferença estatística entre os três grupos. Porém, o grupo C, na mensuração da área medular, apresentou uma área média maior (1,41 ± 0,42) em relação aos outros dois, seguido do grupo OVX (1,37 ± 0,16), o qual, por sua vez, obteve valores superiores ao grupo OVX+T (1,24 ± 0,15) (Figura 6).…”