Inorganic Phosphorus Levels Research Articles

Effect of graded levels of phosphorus on growth and mineral concentration in giant African catfish Heterobranchus bidorsalis.

Eleven diets (D1 - D11), designated as treatments (T1 - T11), supplemented with different levels of inorganic phosphorus (P) (CaHPO 4 ) were fed to Heterobranchus bidorsalis (10.8 4 ) were fed to Heterobranchus bidorsalis (10.8 4 ) were fed to Heterobranchus bidorsalis (10.8 ± 0.02 g) to determine the optimum P requirement. D1 - D11 contained total P of 10.2, 10.4, 11.0, 11.9, 12.3, 12.6, 13.4, 13.9, 14.2 14.7 and 15.4 g kg -1 respectively. After 84 days of feeding trial, there was increase in fish growth up to T5 with 12.3 g P kg -1 diet, followed by consistent decline in growth towards T11 with the highest P content. However, fish in T5 had the best (P -1 diet as optimum requirement for the growth of Heterobranchus bidorsalis .

AVALIAÇÃO HISTOLÓGICA DE FÍGADO, RIM, TIREÓIDE, PARATIREÓIDE E OSSO DE SUÍNOS EM TERMINAÇÃO SUBMETIDOS A DIFERENTES DIETAS

The present experiment aimed to evaluate histological changes in hepatic, renal, thyroid, parathyroid and metacarpian bone tissues of pigs submitted to diets without micro minerals and vitamins, reduced inorganic phosphorus levels and phytase addition in two restriction times. Forty eight 105-days old (66.15±0.14 kg) female pigs received experimental diets with corn, soybean and wheat meal. The animals were randomly distributed in six groups: standard diets (T1); composed of corn, soybean meal and wheat meal; standard ration without micro mineral and vitamin supplement (T2); T2 ration with phytase (T3); T2 ration reducing 1/3 of inorganic phosphorus with phytase (T4); T2 ration reduced 2/3 of inorganic phosphorus with phytase (T5); and T2 ration with complete reduction of inorganic phosphorus with phytase (T6). The experiment was carried out in two phases: Phase 1. 24 animals, 35 days of restriction and slaughter at 150 days of age (106.65 kg), and Phase 2, 24 animals, 60 days of restriction and slaughter at 175 days of age (123.87 kg). At slaughter, samples of liver, kidney, thyroid, parathyroid and metacarpian bone were collected from all animals. The samples were fixed in 10% buffered formaldehyde and stained by hematoxilin and eosin (HE). The Mallory’s trichrome stain was used in bone sections. Kidney histopathological evaluation showed interstitial nephritis in 37 animals (77%). Mononuclear inflammatory infiltrated was observed focally on liver of 15 animals (31.25%). Treatments didn’t promote histopathological changes in thyroid and parathyroid glands. The metacarpian bone microscopy showed low osteochondrosis in animals of different treatments and phases. However, in experimental time, clinic signs of bone metabolic disease and osteochondrosis were not verified. Phytase addition was efficient to provide phytic phosphorus in the diet, since no macro or microscopic lesions characterizing phosphorus deficiency in the bone samples were present. KEY WORDS: Histopathologic changes, micro minerals, phytase, phosphorus restriction, vitamins.

ELECTROLYTE IMBALANCE FOLLOWING ILEAL URINARY DIVERSION

SUMMARY Measurements of serum electrolytes were made in 38 patients in whom ileum was used in the urinary tract. A high incidence (61 per cent.) of transient early hyperchlorzmic acidosis due to reabsorption was found but most patients were able to compensate for it. However, 27 per cent. of patients were unable to compensate because of permanent renal damage and they developed chronic hyperchlorzmic acidosis. Normal levels of serum uric acid, calcium and inorganic phosphorus were found in all of the patients. For monitoring renal function in patients with ileal urinary diversion measurements of serum creatinine were found to be more useful than estimation of blood urea.

RETIRADA DO SUPLEMENTO MICROMINERAL-VITAMÍNICO, REDUÇÃO DE FÓSFORO INORGÂNICO E ADIÇÃO DE FITASE EM RAÇÕES DE SUÍNOS NA FASE DE TERMINAÇÃO

The experiment aimed to evaluate the effect of mineral-vitamin supplement withdrawal associated to inorganic phosphorus and phytase addition on swine performance and carcass characteristics in finishing phase. 48 hybrid swine females with initial average weight of 66,34 kg and final average weight of 106,14 kg were housed in 24 stalls for 38 days and allotted to a completely randomized experimental design with six treatments (T1 – basal feed; T2 – basal feed without mineral vitamin supplement; T3 – basal feed without mineral vitamin supplement with phytase; T4 – basal feed without mineral vitamin supplement less1/3 of inorganic phosphorus with phytase; T5 - basal feed without mineral vitamin supplement less 2/3 of inorganic phosphorus with phytase and T6 – basal feed without mineral vitamin supplement and inorganic phosphorus with phytase) with four replications of two animals each. Daily weight gain, total average weight gain and feed:gain ratio were determined and carcass characteristics were evaluated: loin eye area, backfat depth, carcass length, carcass weight and carcass yield. Although reduction in inorganic phosphorus levels or phytase addition had no influence in carcass characteristics (P>0,05), there was significant effect in performance (P<0,05), resulting in less average feed intake, weight gain and feed:gain ratio. Likewise, reduction in inorganic phosphorus levels or phytase addition under the conditions of this trial did not improve economic efficiency when compared to basal feed. KEY WORDS: Finishing phase pig, phosphorus, phytase.

A Case Report of an Anorexia Nervosa Patient With End‐stage Renal Disease Due to Pseudo Bartter's Syndrome and Chinese Herb Nephropathy Requiring Maintenance Hemodialysis

The extent of end stage renal disease (ESRD) has not been well documented in anorexia nervosa (AN). We herein describe a 47-year-old female with ESRD who required maintenance hemodialysis (HD) following a 27 year history of AN, and seven years of diuretic and purgative abuse. In spite of HD treatment, her serum inorganic phosphorus level remained elevated (10.2-15.8 mg/dL). Tissue degradation due to catabolism, insufficient dialysis treatment, and use of Chinese herbal medicine, including aristolochic acid, are speculated as the cause of her hyperphosphatemia. We also speculated that the causes of her renal dysfunction are as follows: chronic interstitial nephritis caused by pseudo Bartter's syndrome resulting from chronic abuse of diuretics and purgatives, and Chinese herb nephropathy.

Survival And Growth Responses Of Frys Of The African Catfish Hybrid (&lt;i&gt;Clarias gariepinus X Heterobranchus bidorsalis&lt;/i&gt;) To Soluble Dietary Supplements Of Inorganic Phosphorus.

Four (4) isonitrogenous experimental diets with 38.00% crude protein were formulated and replicated three times to include four supplemental inorganic phosphorus (H3PO4) levels of 0.20%, 0.80%, 1.00 and 1.20%. The control experiment (replicated three times) consisted of diets with non-inorganic phosphorus. The dietary treatments were fed to 4-weeks old hybrid of Clarias gariepinus × Heterobranchus bidorsalis (mean weight, 2.10 ± 0.14 g) at 5% body weight per day for 42 days. The soluble reactive concentration level of the inorganic phosphorus (SRP) in experimental water was investigated, the growth response and survival of the fish evaluated. The results indicated that the water treated with the control diet (0.03 mg/l) had a higher concentration of SRP than any of the H3PO4-supplemented diet. The range values of SRP in water with dietary 0.60% and 0.80% P-supplementation did not vary significantly (P > 0.05). There were significant differences (P < 0.05) in the range values of SRP of water treated with 1.00%, 1.20% and 0.00% P (control) diets, even though the values for the mean weight gain (MWG) and food conversion ratio (FCR) were not significantly different (P > 0.005). The phosphorus gain/loss (PGL) values of fish were only significantly different (P < 0.05) between the 0.80%, 1.20% and the control diets. The non-significant difference (P > 0.05) of the PGL of fish when 0.60% P and 1.00% diets were applied apparently corresponded with non-significant difference (P > 0.05) recorded for the SRP of water treated with 0.60% and 0.80% P diets. Keywords:Inorganic phosphorus, soluble reactive concentration, supplemental diets.Journal of Technology and Education in Nigeria Vol. 10 (1) 2005: pp. 11-19

Soil and phosphorus redistribution along a steep tea plantation in the Feitsui reservoir catchment of northern Taiwan

Feitsui reservoir, the major water supply of Taipei city, has shown declining water quality in recent years. The reservoir is located in an area famous for tea cultivation, and the question arises as to whether the hillside tea plantations have contributed to increased sediment and nutrient discharge into the reservoir. In this study, soil and phosphorus redistribution were examined along a steep tea plantation in the reservoir's catchment and the provenance of reservoir sediment was assessed. Fallout radionuclides were used as soil erosion/deposition tracers and as markers of sediment sources. Continuous fertilizer application has raised (inorganic) phosphorus levels in the studied tea plantation. The plantation's narrow bench terraces trap eroded material and slow down soil and nutrient translocation. Nevertheless, eroded soil and phosphorus have accumulated on a vegetated toeslope below the tea plantation. The reservoir sediment contained significant amounts of inorganic phosphorus and cesium-137, and application of a mixing model resulted in a surface soil contribution of approximately 30%. This points towards tea plantations as possible sediment and pollutant sources and underlines the necessity of soil conservation strategies, such as the maintenance of vegetated riparian buffer zones. However, other sources, such as landslide debris and urban wastewaters, cannot be entirely ruled out. Further research is needed to better characterize the catchment's soils and sediments and to improve sediment fingerprinting efforts. Potential point and non-point pollution sources need to be examined in detail to better understand how phosphorus enters the reservoir.

Accuracy of PTH assay and corrected calcium in early prediction of hypoparathyroidism after thyroid surgery

To evaluate the accuracy of the intraoperative parathyroid hormone (ioPTH) and 6-hour PTH (6hPTH) assay in predicting transient hypoparathyroidism after thyroidectomy. A nonrandomized prospective study was conducted on patients undergoing thyroid surgery. Of 138 patients undergoing thyroid surgery, intraoperative PTH was measured 10 minutes after gland removal. Serum calcium, magnesium, inorganic phosphorus, albumin, and PTH levels were assayed 6 and 16 hours after surgery and daily until patient discharge. The development of postoperative hypocalcemia was associated with low ioPTH (P < 0.0001) and 6hPTH (P < 0.0001) values, and the decline of PTH from baseline (P < 0.0001). The cutoff for percentage decline of ioPTH and 6hPTH (55.7% and 379%, respectively) was more accurate than an absolute value. Accuracy, and positive and negative predictive values were 88 percent, 63 percent, and 100 percent for ioPTH and 75 percent, 46 percent, and 100 percent for 6hPTH, respectively. With the use of ioPTH decline in association with 16-hour corrected calcium, it is possible to distinguish early normocalcemic patients from hypocalcemic ones in most cases.

Avaliação metabólica da redução de fósforo inorgânico e supressão de microminerais e vitaminas em dietas com fitase para suínos

The experiment aimed to evaluate the effects of diets without micro minerals and vitamins, reduced inorganic phosphorus levels and phytase addition in bone metabolism and renal and hepatic functions in finishing pigs. Forty eight 105-day old females were randomly allotted in six groups: standard diets (T1), composed of corn, soybean meal and wheat meal; standard ration without micro mineral and vitamin supplement (T2); T2 ration with phytase (T3) T2 ration reducing 1/3 of inorganic P with phytase (T4), T2 ration reduced 2/3 of inorganic P with phytase (T5) and T2 ration with complete reduction of inorganic P with phytase (T6). The experiment was carried out in two phases: phase 1: 24 animals slaughtered at 150 days of age (106.65 kg); and phase 2: 24 animals slaughtered at 175 days of age (123.87 kg). The serum parameters evaluated were: total and ionic calcium, phosphorus, calcium/phosphorus ratio, total protein, albumin, AST, GGT, alkaline phosphatase, urea and creatinine. All biochemical parameters were analyzed using commercial kits in an automatic analyzer. The levels obtained for all analyzed parameters ranged within normal established values for this species and age. Inorganic phosphorus decrease in phytase-added diets did not interfere in bone metabolism. Vitamin and mineral supplements withdrawal and progressive decrease of inorganic phosphorus and phytase addition in diets of finishing pigs did not change hepatic or renal function. Micro minerals and vitamin restriction for 60 days during finishing phase in pigs did not lead to clinical changes. KEY WORDS: Bone metabolism, hepatic function, renal function .

Above and below ground impacts of terrestrial mammals and birds in a tropical forest

Understanding the impact of losing trophic diversity has global significance for managing ecosystems as well as important theoretical implications for community and ecosystem ecology. In several tropical forest ecosystems, habitat fragmentation has resulted in declines and local extinctions of mammalian and avian terrestrial insectivores. To assess the ability of a tropical rainforest community in Ivory Coast to resist perturbation from such loss of trophic diversity, I traced feedbacks in above and below ground communities and measured changes in nutrient levels and herbivory rates in response to an experimental exclosure of avian and mammalian terrestrial insectivores. I present evidence that loss of this functional group may result in increased tree seedling herbivory and altered nutrient regimes through changes in the abundance and guild structure of invertebrates. Exclusion of top predators of the forest floor resulted in increased seedling herbivory rates and macro‐invertebrate (&gt;5 mm) densities with strongest effects on herbivorous taxa, spiders and earthworms. Densities of microbivores including Collembola, Acarina and Sciaridae showed the opposite trend as did levels of inorganic phosphorus in the soil. Results were evaluated using path analysis which supported the presence of a top down trophic cascade in the detrital web which ultimately affected turnover of phosphorus, a limiting nutrient in tropical soils. Results illustrate the potential importance of vertebrate predators in both above and belowground food webs despite the biotic diversity and structural heterogeneity of the rainforest floor.

Effects of colloidal iron overload on renal and hepatic siderosis and the femur in male rats

Genetic hemochromatosis is an iron overload disorder, and osteopenic and osteoporotic. Femoral neck bone mineral density (BMD) appears to fall with rising hepatic iron concentrations. A critical role for iron in mediating tissue injury is played via hydroxyl radical formation in nephrotoxicity. We investigated the effects of a colloidal iron overload on renal function, organ siderosis, and femoral bone in male rats. Iron overload reduced body growth, and increased the weights of the liver and spleen. Marked deposition of iron was noted in liver and kidney. Activities of lactate dehydrogenase and alkaline phosphatase were decreased, and the concentrations of blood urea nitrogen and creatinine were increased with the reduction in plasma calcium and inorganic phosphorus levels, i.e. functions of the liver and kidney might be affected by reactive oxygen species such as the superoxide radical, H 2O 2, and the hydroxyl radical produced by overloaded iron. Damage to the proximal tubular epithelial cells of the kidney and a loss of connectivity of cancellous bone in the epiphysis and of trabecular bone in the metaphysis of the distal femur were observed in iron-overloaded rats with a reduction of femoral bone mineral density, i.e. reabsorption of calcium from the proximal tubular epithelial cells of the kidney might be affected and urinary discharge of calcium might be elevated. It was suggested that iron overload gave rise to osteoporosis combined with renal dysfunction and liver iron overload syndrome.

Changes in serum calcium, magnesium and inorganic phosphorus levels during different phases of the menstrual cycle.

The menstrual cycle is a complex process involving the interaction of the hypothalamus, the anterior pituitary, the ovaries and the uterus. The hormonal changes occurring during this cyclic process not only affect oocyte maturation and the endometrial and vaginal environments but can also have an effect on a number of other physiological and biochemical phenomena. We investigated the changes in serum calcium, magnesium and inorganic phosphorus levels during different phases of the menstrual cycle in fifty healthy young women. We found subtle but significant variations in these levels in the menstrual, follicular and luteal phases. The serum calcium level was highest in the follicular phase whereas the serum magnesium level was lowest in the follicular phase; the serum inorganic phosphorus levels was highest in the menstrual phase. These variations could be due to the impact of the changing estrogen and progesterone secretion on the parathyroid glands.

FERRO E IMUNIDADE HUMORAL EM SUÍNOS ALIMENTADOS COM FITASE E NÍVEIS REDUZIDOS DE FÓSFORO

Endogenous enzymes such as phytase have been widely used in swine production to increase phosphorus, amino acid and energy availability from feeds. This study aimed to evaluate the immune system through quantification of blood components associated to iron metabolism and determine humoral immune response elements in pigs fed phytase-added diets without micro minerals and vitamins and partial or total deletion of inorganic phosphorus. Forty-eight crossbred females with initial weight of 60 kg were randomly sorted into six groups of eight animals each, as follows: G1 -standard (complete) ration (control group); G2 - standard ration except that micromineral and vitamin supplement was deleted; G3 - group 2 ration with phytase, G4 - group 2 ration less 1/3 of inorganic P with phytase, G5 - group 2 ration less 2/3 of inorganic P with phytase and G6 - group 2 ration without inorganic P with phytase. Statistical difference (p>0,05) was not recorded neither in white cells and platelet counts nor hemoglobin, serum iron levels, considering all the animals in all treatments. Nevertheless, pigs up to 100 kg that consumed diet without micro minerals and vitamins, total deletion of inorganic P and phytase addition presented increased ferritin levels (p>0,05) when compared to animals fed similar diet with inorganic phosphorus and phytase. The enzyme guaranteed maintenance of iron stocks even in the absence of supplementation. Such difference was not recorded with 120-kg animals fed similar rations. Average total protein, IgG and IgM levels were not influenced by phytase, mineral and vitamin supplementation or inorganic phosphorus levels. The results demonstrate that decrease of inorganic phos-phorus, withdrawal of vitamin and mineral supplements and phytase addition in diets of finishing pigs do not lead to significant changes in hematological, biochemical and humoral immune response parameters. Key-words: Immune system seric ferritin, IgG, IgM, white cells count.

Association of respiratory complications and elevated serum immunoglobulins with drinking water arsenic toxicity in human

We assessed the relationship between chronic arsenic exposure through drinking water with respiratory complications and humoral immune response by measuring serum immunoglobulin profiles in the affected subjects (arsenicosis patients) living in the arsenic endemic rural villages of Bangladesh. The duration of exposure was determined through detailed history of the patients (n = 125) and the levels of arsenic in the drinking water and urine samples were determined. The mean duration of exposure in the patients was 7.4 ± 5.3 y, and the levels of arsenic in the drinking water and urine samples were 216 ± 211 and 223 ± 302 μ g/L, respectively, compared to 11 ± 20 and 29 ± 19 μ g/L, respectively, in the unexposed subjects. There was high prevalence of respiratory complications like breathing problems including chest sound, asthma, bronchitis and cough associated with drinking water arsenic toxicity. Arsenicosis patients had significantly elevated levels of IgG (P < 0.001) and IgE (P < 0.001) while the levels of IgA were also significantly higher (P < 0.005) but IgM were similar to that of the control subjects. Analysis of the clinical symptoms based on skin manifestations showed the levels of both IgG and IgE were significantly elevated during the initial stages while IgE were further elevated with the duration of arsenic exposure. Arsenicosis patients with respiratory complications had mean serum IgE levels of 706 ± 211 IU/mL compared to 542 ± 241 IU/mL in patients without apparent involvement with the respiratory system (P < 0.01). The eosinophil counts in the patients did not differ significantly from the unexposed subjects indicating that elevated levels of serum IgE might not be due to allergic diseases, rather it could be due to direct effects of arsenic. We found significant linear relationships between the levels of serum IgE and inorganic phosphorus (P < 0.05), and serum IgA levels with urinary excretion of arsenic (P < 0.001). These observations suggested that arsenic toxicity caused respiratory complications, induced changes in the humoral as well as mucosal immune responses.

Phytase in diets for Nile tilapia in the growth period

This research was carried out to compare the effect of phytase on performance, in the incorporation and excretion phosphorus in Nile tilápia. Four diets were used: one standard (contol), composed by 3,200 DE kcal ED/kg of ration and 30.0% CP and supplemented with phosphorus (4.0% of dicalcium phosphate), considering the treatment control, and others three, without phosphorus supplementation, with different phytase levels (1,000, 1,500, and 2,000 uf/kg), with four replication, per a period of 82 days. Circular tanks of fiber glass, with constant flow and aeration were used. The results demonstrated that the use of phytase in diets for fish production can reduce the levels of inorganic phosphorus in the diets and minimizing the impacts caused by phosphorus in the production system and in the natural environment and also can improve the productivity, increasing the amount of feed to be supplied and, consequently, facilitating the increase of biomass of fish to be used per production area.

Hypophosphatemic rickets/osteomalacia. - Mainly on patients with PHEX mutations -

Most patients with inherited hypophosphatemic Rickets/Osteomalacia have mutations in the PHEX gene. In this brief review, we focus on the treatment for patients with this mutation. First, molecular basis of inherited hypophosphatemic Rickets/Osteomalacia, followed by pathophysiology of PHEX and its related disorders is described. Next, clinical manifestation of patients with PHEX mutations and the principles of the treatment are explained. Finally, a case with this mutation that has been long followed up is presented. The most common treatment for this disorder is administration of phosphate and vitamin D, both internationally and in Japan. Degree of the increment in serum inorganic phosphorus levels one hour after phosphate administration, in addition to a decrease in alkaline phosphatase levels is valuable in the monitoring of the treatment. During childhood, markers in a longer term, namely, improvement of X-ray findings and that of height velocity are also useful.

Presence of spondyloarthropathy and its clinical profile in patients with hypoparathyroidism

Though spondyloarthropathy has been described in patients with sporadic idiopathic hypoparathyroidism (SIH), the clinical profile is not known. To describe the clinical profile including radiological features of spondyloarthropathy and prevalence of HLA-B27 allele in patients with hypoparathyroidism, and to identify any differences from ankylosing spondylitis. Clinical characteristics and radiographs of pelvis and spine were assessed in 40 consecutive patients with SIH. Radiographs were assessed by radiologist (RS) and rheumatologist (RG) for the features of spondyloarthropathy including sacroiliitis, syndesmophytes and hip joint calcification, and so on. HLA-B27 genotyping was carried out in patients with SIH, and 195 healthy controls using duplex PCR. Fourteen control radiographs were from age-matched normal individuals. Three patients with SIH had clinically overt spondyloarthropathy which closely resembled ankylosing spondylitis. Fourteen (eight females and six males) of the 40 patients with SIH showed radiological changes including syndesmophytes in lower dorsal or dorso-lumbar spine (n = 6), sacroiliitis and new bone formation at the acetabular rim of the hip joint (n = 10). Though all six patients demonstrating syndesmophytes had new bone formation at hip, sacroiliitis was seen in only three of them. None of the 14 controls had syndesmophytes, sacroiliitis or hip joint calcification. The mean (SD) duration of illness (15.4 +/- 8.7 vs. 6.5 +/- 5.9 years, P < 0.01), BMI (24.1 +/- 5.2 vs. 20.8 +/- 3.7 kg/m(2), P = 0.04) and frequency of basal ganglia calcification was higher (100%vs. 57.7%, P < 0.01) in patients who showed changes of spondyloarthropathy in comparison to those without these changes. On multiple logistic regression analysis, only duration of hypoparathyroid illness was associated with spondyloarthropathy with an odds ratio of 1.17 (95% CI = 1.05-1.30, P < 0.01) per year increase in the duration. The mean age, serum total calcium, inorganic phosphorus and serum intact PTH (iPTH) levels were not significantly different between SIH patients with and without spondyloarthropathy. The frequency of HLA-B27 allele was comparable between SIH and the control groups. Thus, spondyloarthropathy is a distinct clinical entity in patients with SIH. Its salient clinical features include presence of syndesmophytes at the thoracic or thoraco-lumbar spine, mild sacroiliitis, calcification at the acetabular margin of hip, preserved bone density, equal distribution in both sexes and lack of HLA-B27 association. Presence of spondyloarthropathy, like basal ganglia calcification, is associated with longer duration of hypoparathyroidism. It is important to differentiate hypoparathyroid-related spondyloarthropathy from ankylosing spondylitis because the management for the two disorders is different.

Metabolismo do ferro em suínos recebendo dietas contendo fitase, níveis reduzidos de fósforo inorgânico e sem suplemento micromineral e vitamínico

O presente estudo foi desenvolvido com o objetivo de avaliar o metabolismo do ferro por meio da determinação do eritrograma, contagem de reticulócitos, dosagem de ferro sérico, ferritina sérica e transferrina sérica de suínos em fase de terminação alimentados com dietas contendo fitase, sem suplemento micromineral/vitamínico e redução dos níveis de fósforo inorgânico (Pi). Foram utilizadas 48 fêmeas suínas de linhagem comercial, com peso inicial de 60kg, distribuídas em seis tratamentos com oito animais em cada grupo. A colheita de sangue foi feita em um grupo de 24 animais com 100kg e em outro grupo de 24 animais com 120kg. Não foram observadas diferenças (P&gt;0,05) nos valores obtidos do eritrograma, da contagem de reticulócitos, de ferro sérico e de transferrina para os animais nos tratamentos testados. Com relação à ferritina, verificou-se que os animais até os 100kg de peso vivo que receberam ração sem suplemento micromineral/vitamínico, sem fósforo inorgânico e com fitase apresentaram valores superiores (P&lt;0,05) quando comparados aos alimentados com ração sem suplemento micromineral/vitamínico, com fósforo inorgânico e contendo fitase. A enzima, mesmo na ausência de suplementação, garantiu a manutenção de estoques de ferro do organismo. Essa diferença não foi detectada para os animais que foram alimentados com as mesmas rações até os 120kg de peso vivo. Os resultados encontrados neste experimento mostram que a redução do fósforo inorgânico, a retirada do suplemento vitamínico e mineral, bem como a adição da fitase, em dietas para suínos em terminação, não desencadeiam alterações significativas no metabolismo do ferro.

Effects of acute exposure to heavy fuel oil from the Prestige spill on a seabird

Large quantities of petroleum products are released into the marine environment as result of tanker wrecks. Such catastrophic events have a dramatic impact on marine ecosystems, affecting a broad range of species. Seabirds are placed at the uppermost trophic level of the marine food chain. Therefore, important toxic effects are expected in these organisms. The recent Prestige oil spill gave the opportunity to test this. A previous study reported that yellow-legged gulls ( Larus michahellis) breeding in the oiled area (17 months after the spill) showed differences both in plasma biochemistry and in the total circulating levels of polycyclic aromatic hydrocarbons (TPAHs) in blood regard to gulls sampled in clean areas. In the present study, wild yellow-legged gulls were fed with heavy fuel oil from the Prestige oil spill (P-gulls) and compared with control gulls (C-gulls) fed only with the vehicle (vegetable oil). Consistent with the cited previous findings, gulls fed with fuel oil showed reduced glucose and inorganic phosphorus levels in plasma, as well as a trend to significantly reduced creatinine values. In addition, glucose concentration was negatively related to TPAH levels. Males but not females fed with fuel oil showed higher plasma activity of asparatate aminotransferase (AST) than controls. With regard to plasma activity of gamma-glutamyl transferase (GGT), the results were opposite to the previous study. The GGT activity increased in C-females, apparently to meet with increased liver metabolism due to egg laying demands, but not in P-females. Differences to the previous study possibly reflect different adaptive responses of these enzymes to an acute short-term exposure to heavy fuel oil. Since the yellow-legged gull belongs to a complex of species widely distributed throughout the Northern hemisphere, the results as a whole might provide a tool for future evaluations of short- and long-term effects of oil spills on seabirds. Decreased glucose and inorganic phosphorus levels in plasma are expected in both short- and long-lasting exposures to fuel oil, whereas responses of AST and GGT enzymes would depend on both the sex of individuals and the temporal pattern of exposure.

Sublethal toxicity of the Prestige oil spill on yellow-legged gulls

The Prestige oil spill in November 2002 is considered the biggest large-scale catastrophe of its type in Europe, thousands of seabirds dying in the subsequent months. Here, the total concentration of 16 polycyclic aromatic hydrocarbons (TPAH) was measured in the blood cell fraction of adult and chick yellow-legged gulls ( Larus michahellis) from unoiled and oiled coastal areas in North Western Spain. In addition, hematocrit, plasma metabolites, electrolytes and enzymes, as well as body mass were determined in the same individuals. Our results strongly suggest the presence of health damages of sublethal nature in adult gulls breeding in oiled colonies 17 months after the Prestige oil spill. This is supported by the following evidences: (1) gulls sampled in unoiled and oiled colonies differed in blood TPAH levels, (2) gulls sampled in unoiled and oiled colonies differed in several blood parameters indicative of physiological disorders, and (3) TPAH in blood was significantly related to several of these parameters. Differences in the level of asparatate aminotransferase (AST), gamma-glutamyl transferase (GGT), total protein, glucose and inorganic phosphorus suggest damages on some vital organs (i.e. liver and kidney) in adult birds from oiled areas. Meanwhile, chicks presented weaker effects than adults, showing only between-area differences in hematocrit. Since TPAH levels in blood did not differ between both age-groups, the stronger effects on adults should be due to their longer exposure to these pollutants and/or to severe exposure in the months following the spill. The presence of PAHs in chicks indicates that these pollutants were incorporated into the food chain because nestlings would have been only exposed to contaminated organisms in the diet (e.g. fishes and crustaceans). Our findings support the view that PAHs may deeply alter the physiology of seabirds, and emphasize the necessity of quantifying the circulating levels of these compounds in order to evaluate the sublethal effects associated to large oil spills.