Impact of pulp and paper mill effluent on egg hatchability of pike (Esox lucius L.)
Toxicants affect reproduction often at concentrations well below lethal levels. Also, the acidification of fresh waters has been shown to cause extinction of teleost fish populations usually through a failure of recruitment from younger generations. Both field and laboratory studies have documented that the greatest susceptibility to low pH occurs in the early developmental stages (e.g. Lee et al. 1983; Peterson 1984). Also low concetrations of metals (Horning & Neisel 1979; Ozoh 1979, 1980) and environmental accumulation of xenobiotics (Ozoh 1979; yon Westerhagen et al. 1981) diminish egg hatchability. In numerous toxicological studies egg hatchability has been a more sensitive indicator of toxic action than the other parameters studied (e.g. Henderson et al. 1981; DeGraeve et al. 1982; Lewis & Wee 1983). However, only relatively recently have the effects of bleached kraft pulp mill effluent (BKME) on fish reproduction (zebrafish Branchydanio rerio) been studied (Viktor et al. 1980; Viktor 1982) and no recipient species have been used.
Toxic effects of pulp and paper-mill effluents on male reproductive organs and some systemic parameters in rats.
The effect of pulp and paper-mill effluents on terrestrial animals was investigated using male albino rats as a test organism, under controlled laboratory conditions. Effluent consumption for 15 days caused a reduction in the relative weight of the testis (mg/100g body weight), compared to the control rats. The effects were not so pronounced in other regions of the male reproductive tract. Biochemical analysis revealed a drop in the activity of epididymal α-glucosidase in the effluent-treated animals. Although sperm collected from the cauda epididymis appeared morphologically normal, a decline in total sperm count and number of motile sperm was seen. The circulating level of testosterone in effluent-treated rats was slightly lower in some groups of rats given effluent treatment compared to controls. The level of progesterone and oestradiol, however, remained unaffected. Hematological and serological analyses suggest that effluents could produce anemia, liver and kidney dysfunction in rats. This inference stems from the altered blood cell counts, enhanced bilirubin and urea concentration in blood and high activity of serum GOT and GPT observed in effluent fed animals compared to controls. It is concluded that besides the general toxicity, the effluent affects the male reproductive system predominantly at the level of the testis.
Morphological characterization of Eustrongylides sp. larvae (Nematoda, Dioctophymatoidea) parasite of Rhinella marina (Amphibia: Bufonidae) from Eastern Amazonia.
Absctract Eustrongylides spp. nematodes have birds as final hosts and uses other vertebrates as intermediate/paratenic host (fish, amphibians and reptiles) and have zoonotic potential. In amphibians, the larvae may be located in the subcutaneous tissues, liver and mesentery, between the muscle fibres, especially in the lower limbs. Rhinella marina, which is widely observed in Brazil, has exhibited complex diversity in its helminth fauna, reflecting the unique habitat of the Amazon biome. For the first time, this study describes the morphological aspects of third-stage larvae of Eustrongylides sp. in Rhinella marina from Santa Cruz do Ararí, Marajó Archipelago, Eastern Amazonia, using light and scanning electron microscopy.