The oestrogenic Fusarium toxin (zearalenone) in hay as a cause of early abortions in the cow

In this study, the occurrence of a series of early abortions in a herd of cattle kept at an experimental station in North Savo has been described, the cause of which has evidently been hay feed in which the toxin zearalenone had formed. Several early abortions occurred in this particular herd 30-90 days after artificial insemination had been performed. It was proved by means of a liquid chromatograph test that the hay contained 10 ppm zearalenone, and a biological experiment with rats gave a clear indication of its oestrogenic strength by means of the chloroform extract obtained with the hay. Early abortions ceased to occur after feeding with the suspected feed was discontinued. The cows were on heat again 2-23 days after the early abortions had occurred, though they subsequently experienced difficulties in becoming pregnant.     

Effect of postpartum live weight loss on reproductive functions in dairy cows

Postpartum loss of live weight in dairy cows and its association with reproductive functions were studied in a total of 84 (42 Ayrshire and 42 Friesian) cows. The cows were divided according to type of feed into 2 groups of equal size: a hay-urea group and a silage group. The duration of the study was 3 years. All 84 cows were followed during their first postpartum period, 63 during 2 and 57 during 3 consecutive postpartum periods.The resumption of ovarian function was monitored by means of a thrice weekly milk progesterone assay between calving and the first insemination.Live weight changes during the first 30 and 60 days post partum were compared between the 2 breeds and the 2 feed groups.After the second parturition, the mean live weight loss within 30 and 60 days post partum was roughly twice as high (11%) as after the first (4%) and third (6%) carvings. Breed had no significant effect on weight change. The cows in the silage group lost slightly more weight after each parturition than those in the hay-urea group. Low, but statistically significant correlations were noted between weight loss post partum and reproductive functions. The interval from calving to onset of the first visible oestrus was 6 days longer, and to pregnancy 8 days longer in cows which lost more than 10% live weight within 60 days post partum than in those which lost less than 10% (p<0.05). The fertility rate at first insemination (53.1%) was lower in cows which lost more than 10% weight than in those (74.4%) which lost less than 10% (p<0.01). Heat detection rate was not affected by weight loss.     

Effects of Leachate Irrigation on Landfill Vegetation and Subsequent Methane Emissions

Short-rotation tree forests are irrigated with landfill leachate to reduce both leachate volume and nutrient content. It is of interest both for leachate treatment and energy recovery to optimise the productivity of such plantations. This study's aim was to investigate the effects of irrigation on soil quality, tree growth and on emissions of landfill gas (LFG) produced in the wastes. Soils irrigated with leachate had a higher average nutrient and organic matter contents, and a lower dry solids content. Larger trees occur on plots irrigated with leachate, presumably due to the positive effect of water and nutrient supply. The willows used in this experiment seemed to be tolerant of high carbon dioxide concentrations, as no statistically effect arising from LFG emissions could be linked to tree growth. Methane oxidation levels between 50 and 950 mol m^-2 yr^-1 were observed. The positive correlation between soil methane oxidation capacity and tree presence is an interesting perspective on reduction of methane emissions by landfill's top cover vegetation type. Optimising methane oxidation using vegetation as a ‘cover crop’ could reduce the amount of methane discharged into the atmosphere.