Now showing 1 - 4 of 4
  • Publication
    Cadmium and other heavy metal concentrations in bovine kidneys in the Republic of Ireland
    In Ireland, an estimated 15% of Irish soils exceed the EU threshold limit for soil Cd of 1 mg/kg. The aim was to determine the concentrations of Cd and other heavy metals (As, Hg and Pb) in kidneys collected from cattle at slaughter. Systematic sampling of eligible animals (animals that were born and reared until slaughter in the same Irish county) at the time of slaughter was conducted, until a threshold number of animals from all 26 counties and 6 age categories was reached. A predictive surface of soil Cd was generated, by kriging the Cd values of 1310 previously reported soil samples. A linear regression weighted model was developed to model kidney Cd concentration, using the risk factors of age, sex, breed, province and estimated soil Cd concentration. Kidney Cd (n = 393) concentrations varied between 0.040 and 8.630 mg/kg wet weight; while concentrations of As, Hg and Pb were low. The estimated weighted proportion of animals with a high (≥ 1 mg/kg) kidney Cd concentration was 11.25% (95% CI: 8.63–14.53%). Key predictors for high kidney Cd concentration were soil Cd, animal age and province. At a soil Cd concentration of 1.5 mg/kg, it was predicted that an age threshold to avoid exceeding a kidney Cd concentration of 1 mg/kg in most animals would be ~ 3 y in Connacht, > 4 y in Ulster, and > 5 y in Leinster and Munster. In naturally occurring areas of high Cd levels in soils in Ireland, the Cd level in bovine kidneys can exceed the current EU ML of 1 mg/kg in older animals. Kidneys of most cattle under three years of age will conform with EU requirements.
      326Scopus© Citations 28
  • Publication
    Hormonal composition of follicular fluid from abnormal follicular structures in mares
    The objective was to characterise the hormonal composition of follicular fluid from mares with distinct anovulatory-cystic follicles. Follicular fluid was aspirated from six mares that presented with cystic follicles and from pre-ovulatory follicles of five normal mares (controls). Differences in progesterone, oestradiol, testosterone, IGF-I and IGF binding were analysed using Fisher's exact test. There were greater (P<0.03) follicular fluid oestradiol concentrations in normal follicles and the testosterone concentration of the cystic fluid was greater (P<0.05) than that of the normal fluid. There also was a greater (P<0.03) percentage of IGF-I binding and lower (P<0.02) IGF-I concentrations in the fluid collected from the cystic structures compared with the fluid from normal follicles. Despite the limited number of animals, the fact that fluid aspirated from cystic follicles had higher testosterone and lower oestradiol concentrations could be of diagnostic value when a practitioner wants to distinguish between a cystic and non-cystic persistent follicle. The research reported here also indicates a likely role for the IGF system in the pathogenesis of the development and maintenance of anovulatory follicular structures in mare ovaries.
      557Scopus© Citations 3
  • Publication
    Ergot alkaloid intoxication in perennial ryegrass (Lolium perenne): an emerging animal health concern in Ireland?
    Four primary mycotoxicosis have been reported in livestock caused by fungal infections of grasses or cereals by members of the Clavicipitaceae family. Ergotism (generally associated with grasses, rye, triticale and other grains) and fescue toxicosis (associated with tall fescue grass, Festuca arundinacea) are both caused by ergot alkaloids, and referred to as 'ergot alkaloid intoxication'. Ryegrass staggers (associated with perennial ryegrass Lolium perenne) is due to intoxication with an indole-diperpene, Lolitrem B, and metabolites. Fescue-associated oedema, recently described in Australia, may be associated with a pyrrolizidine alkaloid, N-acetyl norloline. Ergotism, caused by the fungus Claviceps purpurea, is visible and infects the outside of the plant seed. Fescue toxicosis and ryegrass staggers are caused by Neotyphodium coenophalium and N. lolii, respectively. Fescue-associated oedema has been associated with tall fescue varieties infected with a specific strain of N. coenophialum (AR542, Max P or Max Q). The name Neotyphodium refers to asexual derivatives of Epichloe spp., which have collectively been termed the epichloe fungi. These fungi exist symbiotically within the grass and are invisible to the naked eye.The primary toxicological effect of ergot alkaloid involves vasoconstriction and/or hypoprolactinaemia. Ingestion of ergot alkaloid by livestock can cause a range of effects, including poor weight gain, reduced fertility, hyperthermia, convulsions, gangrene of the extremities, and death. To date there are no published reports, either internationally or nationally, reporting ergot alkaloid intoxication specifically associated with perennial ryegrass endophytes. However, unpublished reports from the Irish Equine Centre have identified a potential emerging problem of ergot alkaloid intoxication with respect to equines and bovines, on primarily perennial ryegrass-based diets. Ergovaline has been isolated in varying concentrations in the herbage of a small number of equine and bovine farms where poor animal health and performance had been reported. Additionally, in some circumstances changes to the diet, where animals were fed primarily herbage, were sufficient to reverse adverse effects. Pending additional information, these results suggest that Irish farm advisors and veterinarians should be aware of the potential adverse role on animal health and performance of ergot alkaloids from perennial ryegrass infected with endophytic fungi.
      364Scopus© Citations 18
  • Publication
    Cadmium exposure and consequences for the health and productivity of farmed ruminants
    This paper reviews Cd exposure and consequences for the health and productivity of farmed ruminants. In farmed ruminants, Cd exposure may be associated with a number of different activities, including industrial processing, mining, and agricultural practices, and is also higher in soils in some geographic regions. Cd kidney concentrations increase with age and Cd exposure. Although Cd toxicity in farmed ruminants has been demonstrated experimentally, there are no published reports of naturally occurring Cd toxicity in farmed ruminants. Clinical signs of Cd intoxication are unlikely with a daily dietary Cd intake of less than 5 mg/kg feed, which is 5–10 times higher than the maximum permitted Cd concentration in ruminant feed in the European Union. In farmed ruminants, Cd levels in tissue are largely dependent on the Cd content of diet. However, many factors affect Cd availability, relating to soils, plants and the presence of other trace elements including Ca, Cu, Fe, Mn, Mo, Se and Zn. Experimental studies have highlighted the ability of Cd to alter trace element status, and the protective effect of good mineral status, however, there remain gaps in knowledge of the impact of these interactions on the health and productivity of farmed animals.
      411Scopus© Citations 80