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This study examined the potential of pulp mill effluent from pulp producing countries (Canada, Brazil, New Zealand) to affect fish reproduction. Specifically, the estrogenic effects in juvenile rainbow trout (Oncorhynchus mykiss) pulse-exposed to 11 different mill effluent extracts (intra peritoneal IP-injections of SPE-DCM non-polar fraction). The results indicated that effluent extracts were estrogenic in juvenile trout irrespective of the gender, reflected by increasing level of plasma vitellogenin (VTG) (Brazil > New Zealand > Canada). In spite of the high variability observed among mills, differences in VTG levels were related to the type of mill process (kraft > ECF-kraft > TMP). Moreover, effluent treatments did not appear to significantly decrease VTG induction. A consistent estrogenic effect was observed in those mills that process a combination of feedstocks (softwood, and hardwood), with the highest increase in VTG related to eucalyptus feedstock. The authors' results demonstrate significant estrogenic effects of pulp mill effluents on chronically exposed juvenile trout, suggesting in vivo metabolic activation of precursors is necessary to cause the observed increases in VTG levels. This molecular estrogenic response provides a useful starting point for predicting population-level impacts through the Adverse Outcome Pathway (AOP) approach methodology. This article is protected by copyright. All rights reserved

Paper sludge composted or stored in static piles for six months was compared to raw and lime-stabilized sludge in a three-year pot experiment (loam) and a four-year field experiment (silt loam) at rates of up to 40 t DM ha -1 . The original sludge contained equal amounts of fibre sludge and biological sludge, mixed with bark in 1:1 ratio to improve the structure. The N content in composted sludge (1.30%) was markedly lower than that of the uncomposted piles (1.98%), indicating significant loss during composting. The yield results were generally inversely proportionate to the C:N ratios of the sludges applied. Sludge from the uncomposted piles gave significant grain yield increases in the year following sludge application, while the other sludge types gave variable results. In the residual years there was, generally, a small but positive effect on yield from all the sludge types. The N and P content in grain generally increased with sludge application, but only the higher rates gave statistically significant increases. Sludge application also increased the Zn content in grain, while Mn, B and Cu was less affected. The increase in Cd content was very small. The 40 t ha -1 sludge rate tended to increase the residual mineral N in soil at the field site and thus the risk of nitrate leaching.

The purpose of this paper is to identify the nest materials, some physical characteristics and the elemental composition of the nest of Dolichovespula saxonica (Fabricius, 1793). The nest surfaces were observed with a stereomicroscope and scanning electron microscope (SEM). In the inner surface of the D. saxonica nest the medium thickness of the fibers in the envelope and comb varied between 7.14 and 26.9 μm, respectively and averaged 16.4 μm. In the outer surface of the nest the medium thickness of the fibers in the envelope and comb were between 3.52 and 5.70 μm, respectively and averaged 4.63 μm. The nitrogen concentration of the nest of D. saxonica was 0.616% and the amount of protein was 3.08%. The percentages of the fibers, saliva, oil and the water absorption capacity were calculated as 67–70%, 23–30%, 12–18% and 110–140%, respectively. However, the amount of the element Cadmium (Cd) in the nest was found to have a value of 0.2 ppm. The major compounds of wasp nests are plant fibers, saliva and oil. However, the concentrations and ratios of the nest material compounds depend on the plant variety, place of origin, and time of harvest as well as on the processing and saliva conditions. The colors of the nest are beige, cream and grey with long dark brown lines. As a result of our study, we have found that the rates and quantities of physical characteristics, elemental composition and the fibers in the envelope and comb of the nest of D. saxonica change with environmental conditions.

Use of organic by-products as soil amendments in agricultural production exemplifies a strategy for converting wastes to resources. The overall objective of this research was to evaluate the short- and intermediate-term effects of repeatedly amending sandy soil with paper mill residuals (PMR) and composted PMR in a vegetable rotation in Wisconsin's Central Sands. Specifically, we investigated the effects of PMR and composted PMR on total soil C and related these to changes in water-holding capacity and plant-available water (PAW). Amendment effects on irrigation requirements were estimated with a simple soil water balance model. The experimental design was replicated five times as a randomized complete block with four organic amendments: raw PMR, PMR composted alone (PMRC), PMR composted with bark (PMRB), and peat applied at two rates and a non-amended control. All amended treatments significantly increased total soil C relative to the nonamended control following applications in 1998 and 1999. One year following the second serial amendment, all PMR treatments increased PAW by 5 to 45% relative to the control. There was a significant positive linear relationship between total soil C and PAW. All amended treatments reduced the average amount of irrigation water required for potato production by 4 to 30% and the number of irrigation events by 10 to 90%. There was a clear trend of greater reduction in irrigation requirements with more carbon added. The cumulative effects of repeated additions of PMRB suggest that certain composts might sustain elevated PAW and reduce irrigation requirements beyond one year.

Rainbow trout Oncorhynchus mykiss fry exposed to a paper mill effluent showed increased EROD (ethoxyresorufin-O-deethylase) activity and reduced territorial aggression in mirror image stimulation (MIS) tests. These results suggest that the MIS test could be a useful tool to detect sublethal behavioural effects of pollution in fish fry.

This study was conducted to establish an appropriate mixture ratio of fly ash (F) to optimized cow dung-waste paper mixtures (CP) to develop a high-quality vermicompost using earthworms (). Fly ash was mixed with cow dung-waste paper mixtures at ratios of (F:CP) 1:1, 1:2, 1:3, 2:1, and 3:1 or CP alone and composted for 14 wk. Olsen P, inorganic N (NO, NO, and NH), C:N ratio, ash content, microbial biomass C, and humification parameters were measured together with scanning electron micrograph images to determine compost maturity. Based on C:N ratio, the extent of vermidegradation of the waste mixtures followed the decreasing order (F:CP) of 1:31:21:1CP alone2:13:1. Similarly, Olsen P was significantly higher (0.05) where earthworms were added. The mean percentage increase in extractable P was in the order CP alone1:21:31:12:13:1, with earthworm addition almost doubling P release across the 1:1, 1:2, and CP alone treatments. Fly ash incorporation enhanced conversion of organic N to the plant-available inorganic forms, with the 1:3 treatment resulting in the highest conversion. Scanning electron micrograph images confirmed the extent of vermidegradation reflected by the various humification parameters determined. Fly ash incorporation at the 1:2 ratio proved to be the most appropriate because it allows processing of more fly ash while giving a vermicompost with desirable maturity and nutritional properties.

The aqueous fraction of the tear film and the horizontal palpebral fissure length (HPFL) were measured in exotic and laboratory animals, specifically saffron finches (Sicalis flaveola), chestnut-bellied seed-finches (Sporophila angolensis), red-eared sliders (Trachemys scripta elegans), rats (Rattus norvegicus) and mice (Mus musculus). These species possess small eyes making it difficult to perform the typical Schirmer tear test. Measurement of the aqueous fraction of the tear was performed using the standardized endodontic absorbent paper point tear test (PPTT), accomplished with manual restraint by a single operator. The following results were obtained: saffron finches (n = 42)-HPFL (4.46 ± 0.09 mm) and PPTT (5.10 ± 0.26 mm); chestnut-bellied seed-finches (n = 38)-HPFL (4.77 ± 0.05 mm) and PPTT (4.11 ± 0.34 mm); red-eared sliders (n = 56)-HPFL (8.59 ± 0.08 mm) and PPTT (8.79 ± 0.38 mm); rats (n = 60)-HPFL (6.45 ± 0.09 mm) and PTT (6.18 ± 2.06 mm); and mice (n = 22)-HPFL (3.59 ± 0.27 mm) and PPTT (4.39 ± 1.45 mm).

Four pulp and paper mills discharge their effluents in the same section of the Biobio River in central southern Chile. Pulp mill effluents are a very complex mixture with characteristics that depend on the type of raw material, the process technology, and the effluent treatment. To investigate the effect of pulp mill effluent discharges, immature Oncorhynchus mykiss were exposed to river sediments in the laboratory for 29 d. Three sampling areas were defined in a spatial gradient in the river: Preimpact, impact, and postimpact zones relative to the pulp and paper mill discharge areas. Ethoxyresorufin-O-deethylase activities were significantly higher in fish exposed to impact and postimpact sediments when compared to those exposed to preimpact sediments, and higher levels of vitellogenin were observed in the plasma of female fish exposed to impact and postimpact sediments. Histological analysis of the gonadal tissue showed an induction of gonadal maturation in fish exposed to sediment coming from the impact and postimpact zones (oocytes in a vitellogenic state). No site differences were observed in erythrocytes, although differences were noted in the leukocytes in the exposure areas. Finally, the biomarker approach showed evidence that the sediment associated with pulp mill effluent discharges produces some effects in fish under laboratory conditions.

Rainbow trout were exposed to a secondary treated, thermomechanical/bleached kraft pulp and paper effluent in 12,000-L, flow-through exposure tanks at an environmental research facility located at a pulp and paper mill in Kawerau, New Zealand. Trout (age, 2+ years) were obtained from a local hatchery and exposed either to upstream river water or a nominal concentration of 12% (v/v) effluent diluted in upstream river water. Three treatment groups were used: Effluent exposure that started approximately three months before gonadal growth (eight-month total exposure), effluent exposure that started approximately halfway through gonadal development (two-month total exposure), and trout exposed to reference water alone for the total duration of the experiment. Trout were sacrificed just before spawning; exposure, growth, and reproductive endpoints were assessed during and at the termination of the experiment. Reduction in growth was observed in both sexes in the eight-month treatment group relative to the river water reference treatment group. No differences were observed in condition factor or liver size in either treatment. Females in the eight-month exposure group also had significantly lower ovary weight. The two-month exposure group showed no differences from the reference group in growth or somatic indices. Estradiol and testosterone were reduced in blood samples taken from the eight-month exposure group by four months into the experiment as compared to the reference treatment. Steroid and vitellogenin levels in individual female trout from this treatment were significantly correlated with gonadosomatic indices (GSI) measured at the termination of the experiment. The GSI was not correlated strongly or consistently with pregnenolone, nor were any treatment-related pregnenolone differences observed, indicating that the steroid hormone reductions likely were not related to cholesterol side-chain cleavage. Male trout showed significant induction of vitellogenin and lower I 1-ketotestosterone during the experiment (only the eight-month group was examined), but this did not result in any significant differences in testes development. Thus, this study has shown an impact of pulp mill effluent exposure on the reproductive physiology of female trout that appeared to be hormonally mediated. Furthermore, the effect could only be manifest when the exposure was initiated before the start of gonad development.

Caging experiments were conducted using hatchery-reared, immature, female rainbow trout (Oncorhynchus mykiss) in three previously defined areas of the Biobio River (south central Chile) representing a pollution gradient from the pulp and paper mill discharges area: a pre-impact area (upstream area, reference location), an impact area (area directly influenced), and a postimpact area (downstream area, less influenced). No significant changes were observed in the physiological index as represented by condition factor (K) and liver somatic index during different sampling times (after 11, 21, and 30 d of exposure). Ethoxyresorufin-O-deethylase activities were significantly higher in trout caged at the impact and postimpact discharges areas (two- to fourfold) compared with the reference (pre-impact) area, and a strong inhibition of acetylcholinesterase activity, reaching 50%, was observed mainly in fish caged at the impact area. A significant endocrine-disrupting effect (reproductive level) was evidenced by significant increments in gonad somatic index and plasma vitellogenin levels combined with an induction of gonad maturation (presence of vitellogenic oocytes) in trout caged at the impact and postimpact areas. These results, generated by an in situ approach, confirmed our group's findings for trout exposed to sediment in the laboratory: discharges of pulp mill effluent in the Biobio River are associated with the effects evaluated at different biological levels.

This study evaluated the effects of bleached and unbleached kraft mill effluent on reproductive success of largemouth bass (Micropterus salmoides). Bass were exposed to effluent concentrations (0, 10, 20, 40, or 80%) for 28 and 56 d. Parameters measured included hepatosomatic index (HSI) and gonadosomatic index (GSI) and plasma concentrations of 17beta-estradiol (E2), 11-ketotestosterone (11-KT), and vitellogenin (VTG). At the end of the 56-d period, bass were moved to hatchery ponds to evaluate spawning success. Spawning mats with eggs either were brought indoors for evaluation of fecundities, hatchabilities, and egg and fry size (measured at age 3 d), or were left in ponds and fry number and size recorded (average age of 14 d). Effluent exposure was verified by measuring resin acids (isopimaric, abietic. and dehydroabietic acids) in bile. Compared to controls, exposed bass had greater concentrations of resin acids in bile. In general, exposed females had lower concentrations of E2 and VTG (> or = 20% effluent), whereas males had lower concentrations of 11-KT (> or = 20% effluent) and increased E2 (> or = 20% effluent). The HSI values increased in females (> or = 10% effluent), and GSI values decreased in both sexes (> or = 40% effluent). Fecundity, egg size, and hatchability did not differ across treatments, but an increase in the frequency of fry abnormalities and a decrease in fry weights was observed at effluent exposures of 40% and higher. However, results from the pond study, revealed a significant reduction in fry growth and survival (> or = 10%). This decline may have been caused by an increased frequency of deformities, in conjunction with alterations of growth. These changes could have resulted from alterations in egg quality because of failure of parental reproductive systems, from acute embryo toxicity after translocation of contaminants from the mother to the developing embryo, or from both.

The Fe-oxide-impregnated paper strip (Pi) test with 0.01 M CaCl 2 has been proposed as an improved soil test for evaluating available P from soils treated with phosphate rock (PR) and triple superphosphate (TSP). However, conclusive evidence for this suggestion has not been reported. This study was conducted to evaluate the suitability of the Pi test for both PR and TSP. In a greenhouse study, two acid soils - Hartsells silt loam (fine-loamy, siliceous, thermic Typic Hapludult) and Hiwassee clay loam (fine, kaolinitic, thermic Rhodic Kanhapludult) - were mixed with ground (0.15-mm, 100-mesh) North Carolina (NC) PR or commercial-grade granular TSP at 0 to 300 mg P kg -1 soil. The soil samples were preincubated for 2 wk before maize (Zea mays L.) was planted and grown for 5 wk. Prior to planting, soil samples were analyzed by three soil tests: Bray I, Pi test with 0.01 M CaCl 2 , and Pi test with 0.02 M KCI. The results showed that NC-PR and TSP were equally effective in increasing dry-matter yield and P uptake by maize in Hartsells soil. North Carolina phsophate rock was approximately 83 and 91% as effective as TSP in increasing dry-matter yield and P uptake, respectively, in Hiwassee soil. When P uptake was plotted against soil test values, both the Bray I and Pi test with CaCl 2 underestimated available P from NC-PR for TSP-treated soil. Available soil P estimated by the Pi test using KCI instead of CaCl 2 was more closely related to P uptake with both NC-PR and TSP. More P was extracted from NC-PR by the Pi test with KCI than with CaCl 2 , whereas no effect was observed for TSP.

Two steers excreting similar quantities of organic matter daily were grazed at pasture during the summer of 1961. The four experiments each involved a preliminary period of five days dosing with Cr2O3 to reach a fairly constant excretion. The steers received a daily dose of Cr2O3 either in oil suspension or in shredded paper. The carriers and steers were interchanged for each trial. For two of the trials each steer in turn was harnessed every other day and all its dung collected in a bag. Total faecal excretion of organic matter was measured from the bagged steer and estimated from the Cr2O3 concentration in a composite sample made up from all dung pats voided during the ten-day collection period. In the other two trials the steers were not harnessed and each dung pat was separately sampled and analysed for Cr2O3 in the organic matter. The average recovery of Cr2O3 in the first two trials was 99·1 (oil) or 94·4% (paper). Calculating the faecal organic matter excretion from the concentration of Cr2O3 in the faeces and the quantity given daily overestimated it by 3·5 to 8·0%. There was no significant difference between shredded paper and oil as carriers of Cr2O3 for estimating the quantity of organic matter excreted. There were 37% and 22% less variation between dung pats in Cr2O3 concentration when this was administered in shredded paper than when given in oil suspension.

Investigations of paper-fiber sludge deposits in the Rainy River, Minnesota, below paper mills were made to determine water characteristics over them with reference to survival of walleye (Stizostedion v. vitreum) eggs and fry and occurrence of bottom fish-food organisms. Sampling of water from the fiber-sludge water interface to the surface showed gradients in oxygen as great as 0.1 ppm to near saturation, and in dissolved sulfides from 0.8 to 0.0 ppm. The most rapid gradient of these materials was in the bottom 20 mm. Levels of sulfides were most affected by current velocity and showed little relation to temperature or season. Walleye eggs placed in test trays on fiber mats had lower survival than those placed 12 inches above the mats and those placed on mineral substrates. Eggs and fry placed on mats died within 48 hours. Laboratory bioassays showed that sulfide levels of 0.3 ppm under controlled conditions approximating river conditions were acutely lethal to Gammarus pseudolimnaeus and walle...

Walleye fingerlings (Stizostedion v. vitreum) were held in 0, 50, 100, and 150 ppm conifer-groundwood fiber at 65 F and 100% oxygen saturation for up to 190 days. Fish were contained in recirculating water-flow systems and fed daily; water and fiber suspensions were changed daily. At the end of the experiment, fish in fiber were 2 to 3% shorter in length and 6 to 11% lighter in weight than controls. Relative condition factor was unchanged. Routine metabolic rate of walleyes in 150 ppm fiber was 18% higher than controls and active metabolic rate was 15% lower. Number of mucous cells on gills of fish from 150 ppm fiber treatments was 38% lower than controls and hematocrit of fish held in fiber averaged 6% lower than controls.

Summary Heat stress negatively impacts the reproductive performance of dairy cows. The main objective of this study was to dissect the genetic basis underlying dairy cow fertility under heat stress conditions. Our first goal was to estimate genetic components of cow conception across lactations considering heat stress. Our second goal was to reveal individual genes and functional gene‐sets that explain a cow’s ability to conceive under thermal stress. Data consisted of 74 221 insemination records on 13 704 Holstein cows. Multitrait linear repeatability test‐day models with random regressions on a function of temperature–humidity index values were used for the analyses. Heritability estimates for cow conception under heat stress were around 2–3%, whereas genetic correlations between general and thermotolerance additive genetic effects were negative and ranged between −0.35 and −0.82, indicating an unfavorable relationship between cows’ ability to conceive under thermo‐neutral vs. thermo‐stress conditions. Whole‐genome scans identified at least six genomic regions on BTA1, BTA10, BTA11, BTA17, BTA21 and BTA23 associated with conception under thermal stress. These regions harbor candidate genes such as BRWD1, EXD2, ADAM20, EPAS1, TAOK3, and NOS1, which are directly implicated in reproductive functions and cellular response to heat stress. The gene‐set enrichment analysis revealed functional terms related to fertilization, developmental biology, heat shock proteins and oxidative stress, among others. Overall, our findings contribute to a better understanding of the genetics underlying the reproductive performance of dairy cattle under heat stress conditions and point out novel genomic strategies for improving thermotolerance and fertility via marker‐assisted breeding.

This study investigates the effect of water temperature on the development rate of eggs and larvae, the duration of the endogenous feeding period and its consequences for recruitment of smelt (Osmerus eperlanus ) in Dutch lakes IJsselmeer and Markermeer. This study measured temperature‐dependent egg and larval development rates as well as mortality rates from fertilization till the moment of absorption of the yolk‐sac and from yolk‐sac depletion onwards in temperature‐controlled indoor experiments. Using multinomial modelling the authors found significant differences in development time of egg development stages under different temperature regimes. Based on historic water temperatures, the model predicted that the larval endogenous feeding period has advanced at a rate of about 2.9 days per decade in a more than 50 year period since 1961, yet there was no change in the duration of the endogenous feeding period. As zooplankton is more responsive to daylight than water temperature cues, a mismatch between the peak of the onset of exogenous feeding of smelt and the peak of zooplankton blooms could lead to high mortality and therefore low recruitment of smelt. Such a mismatch might contribute to a decline in the smelt population in Lake IJsselmeer and Lake Markermeer.

The present study investigated the effects of overripe pulp and green peel extract and powder of banana fruit (Musa. cavendish) on haematological, biochemical, immunological, health, and performance of Holstein dairy calves. In all, 40 newborn calves were randomly divided into four groups of 10 animals. In the control group, animals received no banana meal. In group 1, calves were supplemented with 2 g (dry matter)/kg body weight/day of overripe banana pulp extract. The calves in group 2 were supplemented with 1 g (dry matter) of overripe banana pulp extract/kg body weight/day and 1 g (dry matter) of green banana peel extract/kg body weight/day. The animals in group 3 were supplemented with 2 g/kg body weight/day of green banana peel powder. The feeding period of calves on the tested supplements was 5 days. Blood samples and other evaluations were taken on day 0 (at birth, before supplementation) and on days 7, 15 and 30. Just a trend towards better average daily weight gain was seen in groups 2 and 3 than others (p = 0.073). Significant group and sampling time interactions were seen for the quantities of RBC (group 1 was lower than other groups at day 30), MCV (group 3 was lower than other groups at day 30) and MCH (group 1 was higher than other groups at day 30) (p, In conclusion, banana supplementation in neonatal calves showed that it may has beneficial effects on the values of MCH, bilirubin and average daily weight gain.

Changes in ecosystems after the removal of stress provide a rich source of information for conservation science. We used a long-term regional data set on the performance of white sucker (Catostomus commersonii) collected before and after the closure of a pulp mill to explore recovery in fish. Physiological indicators, including liver enzymes and plasma steroids, showed some compelling changes after the closure of the mill consistent with reduced exposure to pulp mill effluent but did not unequivocally demonstrate recovery. However, persistent signals in these fish may indicate effects of impoundment or discharge of sewage. We also used quantile regression with environmental covariates and bootstrap iteration to determine if systematic variation remained in relative body weight, liver weight, and gonad weight. In fish formerly exposed to pulp mill effluent, we found evidence of improvements (male gonad weight and liver weight of males and females), degradation (gonad weight of females), and no change (body weight). Although the observed patterns may be associated with closure of the mill, some differences were also found at regional locations, suggesting roles of additional stressors and challenging the clear association of change at the Mattagami River exposure site with the closure of the mill. However, fish captured at this location show responses consistent with regional locations, suggesting no residual impacts and highlights the challenges of identifying changes in fish even after large and known interventions. Environ Toxicol Chem 2021;40:162-176. © 2020 SETAC.

The objective of this study was to evaluate the effects of physically effective neutral detergent fiber (peNDF) in rice straw and cassava pulp diets on the chewing activity, ruminal fermentation, milk production, and digestibility in low-producing dairy cows. Eight lactating Holstein crossbred cows were randomly divided into two groups in a crossover design with two dietary treatments over two 21-day periods. The difference in peNDF contents was achieved by balancing the ratio of rice straw, cassava pulp, and concentrate. The high cassava pulp diet had 15.5% peNDF and the low cassava pulp diet had 20.2% peNDF. The results showed that feeding the low cassava pulp diet increased the concentrations of milk protein, milk fat, solids-not-fat, and total solids in the milk. In contrast, the dry matter intake, milk yield, lactose content, chewing activity, nutrient digestibility, ruminal fermentation, and pH were not affected by treatments.

Intensive cultivation and introduction of input‐responsive high‐yielding varieties with application of major nutrients in rice–wheat rotation of Indo‐Gangetic plains (IGPs) lead to multiple nutrient deficiencies. A survey of Indian soils has shown that 40% are deficient in available zinc (Zn), 33% in sulfur (S), and 33% in boron (B). Studies have indicated that application of these nutrients with major nutrients can improve the crop productivity. Keeping the importance of aromatic rice in view, coated‐urea materials and their effects on rice yields, nitrogen (N), and Zn content in different parts and input economics are evaluated. Three field trials are conducted on aromatic rice to test boron‐coated urea (BCU), sulfur‐coated urea (SCU), and zinc‐coated urea (ZnCU) in 2013 and 2014. Results indicate that the highest yields are obtained with 0.5% BCU, 5.0% SCU, and 2.5% ZnCU as zinc sulfate heptahydrate. These treatments increase grain yield by 13%, 25%, and 17.9% over prilled urea (PU). Moreover, 0.5% BCU, 5% SCU, and 2.5% ZnCU register the highest N, S, and Zn contents in bran, husk, grain, and straw. Coated‐urea materials also improve use efficiencies and harvest index of N and Zn over PU. The findings of this study suggest that 0.5% boron, 5.0% sulfur, or 2.5% zinc‐coated urea show improvement in returns and benefit–cost ratio in aromatic rice of western IGPs., Micro–(Zn, B) and secondary (S) nutrients coating onto prilled urea leads to maximized benefits and increased N/Zn–use efficiencies.

We evaluated the chemical compositions of cassava pulp samples produced by four cassava starch factories at different locations in northeast Thailand and the metabolizable energy (ME) of the cassava pulp for cattle. There were significant differences in the P (0.03% ± 0.02%) and K (0.36% ± 0.2%) contents of the samples from different factories (p < .05). Moreover, we found interactions between factory and season in the neutral detergent fiber (36.02% ± 8.8%) and nonfibrous carbohydrate contents (59.33% ± 9.1%) (p < .05). For the evaluation of ME, a crossover-design experiment with four cattle maintained in each of two groups was conducted. There were two dietary treatments at a maintenance level of 1.27% body weight: (1) a control diet, and (2) a cassava pulp diet, containing the control diet at 70.2% and cassava pulp at 29.8% (dry matter [DM] basis). Feeding cassava pulp did not affect energy intake, energy loss, heat production, energy utilization efficiency (except for the urine-to-gross energy ratio), methane production, fecal N, or nutrient digestibility (except for crude protein digestibility). The total digestible nutrients, digestible energy, and ME contents of cassava pulp were 74.4%, 12.9 MJ/kg DM, and 11.3 MJ/kg DM, respectively.

The ability of some pulp mill effluents (PME) to act as reproductive and endocrine disrupters in fish is well documented in the literature. However, changes are not always consistent with regard to species, gender, hormones, or reproductive effects. In the present study, the presence of the first intersexed fish that, to our knowledge, has been found in a Canadian river exposed to PME, is reported. A field survey of the Wabigoon River near Dryden, Ontario, in the fall of 2000 found intersexed walleye (Sander vitreus vitreus) with significantly altered hormone levels and reduced gonad size. The Wabigoon River receives discharge from a bleached kraft pulp and paper mill and a municipal wastewater (MWW) plant. It also has historical sediment contamination (wood fiber mats) contributing to extended periods of low dissolved oxygen under low flow, drought conditions. A mesocosm-based partial life cycle test exposing fathead minnows (Pimephales promelas) to reference water, 20% effluent volume to river volume (v/v), 40% (v/v), or 60% (v/v) PME as well as a field survey of the walleye in the Wabigoon River were conducted. The only change in our mesocosm exposure was a decrease in testosterone in males with increasing effluent concentration and vitellogenin induction in males exposed to 60% (v/v) effluent. These results did not reflect the magnitude of endocrine disruption seen in the wild fish survey. Several hypotheses that may explain these discrepancies are proposed. Specifically, evidence is offered from published studies indicating that either hypoxia or MWW, alone or in combination with PME, may explain the discrepancy between our field experiment and the wild fish survey. The present study illustrates the complexities of multistressor receiving environments and the need for the development of cumulative effects assessment approaches. Environ. Toxicol. Chem. 2010;29:952–965. © 2010 SETAC

The aim of this study was to evaluate the effects of fresh and composted paper sludge on macroaggregate stability of a silt loam under fi eld conditions, and to assess the possible role of carbohydrate fractions and humic substances. The treatments included fresh paper mill sludge (PMS) and its compost (CPMS) applied at a rate of 40 Mg ha -1 with or without a mineral N fertilizer (120 kg N ha -1 ), N fertilizer only (recommended rate of 160 kg N ha -1 ), and an unamended control. Measurements of total and amino sugars and humic substances were made on slaking-resistant aggregates 2 yr after the last of three successive annual applications of the treatments. Compared with the treatments that received no organic amendment, the PMS and CPMS applications increased macroaggregate stability by an average of 45%. The effects of fresh vs. composted amendments on soil macroaggregates and their organic C contents were similar but differences in C composition were observed. Humic acid content of aggregates >2 mm was signifi cantly higher (50%) with CPMS than PMS, although part of this effect could be attributed to the slightly greater C application rate with CPMS. Conversely, glucosamine content, an indicator of fungi abundance, was signifi cantly greater following PMS than CPMS application. We concluded that microorganisms, in particular fungi, were a more important factor of stable macroaggregation in the soil amended with fresh sludge, while humic substances played a greater role in compost-amended soil. These effects were long lasting in the fi eld since they were still noticeable 2 yr after the last application.

The effect of fish consumption on blood pressure is controversial. The authors measured blood pressure and calculated oily fish servings per week in 677 community‐dwellers aged 40 years and older living in rural coastal Ecuador. Using regression models with linear splines, the authors evaluated whether dietary fish intake was related to blood pressure levels, after adjusting for relevant confounders. Mean oily fish consumption was 9.1±5.6 servings per week. There was a nonlinear relationship between systolic pressure and fish servings. In the group of individuals consuming up to five servings per week, each serving significantly reduced systolic pressure by 2.3 mm Hg (P=.020). Any extra serving provided no further effects. The study shows an inverse relationship between oily fish consumption and systolic pressure. Currently recommended amounts of dietary oily fish intake per week (1–2 servings) might be insufficient to exert beneficial effects of fish in the control of blood pressure.

Field measurements of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) concentrations in fish tissues from riverine environments impacted by treated pulp and paper industry effluent in the United States were analyzed. Data from 39 sites in 14 states across the four major U.S. paper-making regions were assembled and analyzed to determine the annual change in lipid-normalized concentrations of TCDD in fish tissue. The results provide strong evidence of a nationwide trend of decreasing lipid-normalized TCDD concentrations in fish tissue, with 84% of the examined sites showing a decrease. While the paucity of data currently limits any conclusions regarding the statistical significance at individual sites, the overall median rate calculated indicates a 0.36 annual fractional decrease in lipid-normalized concentrations of TCDD in fish tissue (0.18 to 0.51, 95% confidence interval); the average annual fractional decrease was 0.35 (0.23 to 0.47, 95% confidence interval). Subdividing fish into benthic and nonbenthic categories resulted in rates which were not significantly different from one another for both the median and mean statistics.

A major pathway for heavy metal exposure in contaminated areas is via consumption of locally produced food. This study investigated the accumulation of lead in Chinese cabbage grown in contaminated soils and estimated the weekly dietary intake. Experiments were conducted to determine the effects of different growth times, concentrations, and lead species (carbonate, nitrate, and sulfide) on the uptake of lead in shoots. Results show that Chinese cabbage accumulated up to 38 mg kg−1 in the shoots. There was a significant difference in lead uptake by plants grown in soils with 400 mg kg−1 (Upper Critical Limit: UCL) and those grown in 600 mg kg−1 (Above Critical Limit: ACL) lead concentrations. However, there was no significant difference in the ACL shoots despite the different growth period. The cabbages grown for eight weeks (at UCL) had four times more lead than those grown for four weeks. The elemental form also affected lead uptake with the lead sulfide (mineral form) having the least uptake and lead carbonate (solution) having the highest. Calculated weekly dietary intake levels of lead were higher (above 0.28 mg kg−1 per human body weight) than the recommended levels for human consumption (0.025 mg kg−1 per human body weight).

Fluctuations in early developmental conditions can cause changes in growth trajectories that subsequently affect the adult phenotype. Here, we investigated whether compensatory growth has long‐term consequences for patterns of senescence. Using three‐spined sticklebacks (Gasterosteus aculeatus), we show that a brief period of dietary manipulation in early life affected skeletal growth rate not only during the manipulation itself, but also during a subsequent compensatory phase when fish caught up in size with controls. However, this growth acceleration influenced swimming endurance and its decline over the course of the breeding season, with a faster decline in fish that had undergone faster growth compensation. Similarly, accelerated growth led to a more pronounced reduction in the breeding period (as indicated by the duration of sexual ornamentation) over the following two breeding seasons, suggesting faster reproductive senescence. Parallel experiments showed a heightened effect of accelerated growth on these age‐related declines in performance if the fish were under greater time stress to complete their compensation prior to the breeding season. Compensatory growth led to a reduction in median life span of 12% compared to steadily growing controls. While life span was independent of the eventual adult size attained, it was negatively correlated with the age‐related decline in swimming endurance and sexual ornamentation. These results, complementary to those found when growth trajectories were altered by temperature rather than dietary manipulations, show that the costs of accelerated growth can last well beyond the time over which growth rates differ and are affected by the time available until an approaching life‐history event such as reproduction.

Background/aims: Ocean bathing has been considered “healthy” for skin, but its efficacy remains testimonial in nature. Our aim was to evaluate the effects of sea water and its main components on experimental irritant contact dermatitis induced by sodium lauryl sulphate (SLS) cumulative irritation. Methods: After open application of 2% SLS for 10 min on volar forearm sites, solutions of sea water, 500 mM NaCl, 10 mM KCl, 55 mM MgCl2, 10 mM CaCl2, or deionized water were separately applied using filter paper discs for 20 min. The procedures were repeated daily for 2 weeks. The effects of the treatment were assessed daily using measurements of transepidermal water loss (TEWL), as an indicator of epidermal barrier function, and capacitance, as a parameter of stratum corneum water content. Results: Sea water, NaCl, and KCl significantly inhibited the increase of TEWL as compared with deionized water (P

Hydrothermal carbonization allows rapid conversion of biomass into a carbon-rich, lignite-like product (hydrochar). It is assumed to have beneficial effects on soil properties and plant growth, but detailed studies are lacking, especially in the field. The objective of our study was to investigate the effect of hydrochar incorporated into arable soils on soil mineral nitrogen (N) content and sugar beet growth. In 2010-2011, a field and a pot trial were conducted. Hydrochars (field: 10 Mg ha; pot: equivalent to 30 Mg ha) processed from sugar beet pulp (HSP) and beer draff (HBD) were tested against an untreated control. As a second factor, mineral nitrogen (N) fertilizer level (field: 0, 50, 100, 150 kg N ha; pot: 0, 100, 200 mg N kg soil) was varied. In both trials, hydrochars reduced initial sugar beet growth, especially when hydrochar with a high C/N ratio (38, HSP) was combined with a low N fertilizer level; high N supply partly compensated for the reduced seedling growth. Without N fertilization, no extractable N was present at the end of the pot trial in the HSP treatment, whereas in HBD even more N was extracted than in the control. This suggests remineralization of previously immobilized N when hydrochar with a low C/N ratio was applied (16, HBD). In the field, beet yield was equal at the high N fertilizer level in HSP and at all N levels in HBD treatment. Our results suggest that hydrochar can decrease plant-available N due to N immobilization. Other potential causes for the observed early growth reduction need to be studied more in detail.

Summary A beef production trial was conducted with 4 groups of 12 young bulls fed intensively on complete dry rations containing respectively 0, 25, 50 and 75% dried sugar beet pulp pellets and 75, 50, 25 and 0% rolled barley. The digestibility of the four rations was determined with wethers. No significant difference was observed in the digestibility of dry matter, organic matter and nitrogen free extract among the treatments, but crude fiber digestibility of the rations increased with increasing amounts of beet pulp in the diets. The mean daily gain amounted to an average of 1280 g and was not significantly different among the treatments. Intake of dry matter per kg gain increased slightly with increasing amounts of beet pulp in the rations. From the analysis of the feed conversion efficiency can be concluded, that the feeding value of dried sugar beet pulp, used in large amounts for beef cattle, was still approximately 10% lower than this of rolled barley with a crude fiber content of 4% in the dry matter. Results of digestibility trials with 8 different lots of dried sugar beet pulp confirm last statement. Calculated net energy content of beet pulp amounted to an average of 90% of this of rolled barley (± 4% crude fiber in the dry matter). Zusammenfassung Der Einsatz von Trockenschnitzeln und gequetschter Gerste in der Bullenmast Zwolf Jungbullen wurden in 4 Gruppen eingeteilt und erhielten 0 (I), 25 (II), 50 (III) und 75 (IV)% Trockenschnitzel und 75 (I), 50 (II), 25 (III) und 0 (IV)% gequetschte Gerste. Die Verdaulichkeit der 4 Rationen wurde an Hammeln ermittelt. Dabei konnte kein signifikanter Unterschied der Verdaulichkeit der Trockensubstanz, der organischen Substanz und der NfE festgestellt werden. Die Verdaulichkeit der Rohfaser stieg mit hoherem Anteil von Trockenschnitzeln in der Ration an. Die durchschnittliche, tagliche Gewichtszunahme der Tiere stieg bis auf 1280 g an. Dabei zeigte sich kein Unterschied zwischen den Rationen. Die Trockensubstanzaufnahme pro kg Gewichtszunahme erhohte sich mit steigendem Trockenschnitzelanteil in der Ration. Aus der Futterverwertung las sich schliesen, das der Futterwert von Trockenschnitzeln in der Fleischerzeugung ungefahr 10% niedriger liegt als der von gequetschter Gerste mit 4% Rohfaser in der Trockensubstanz. Der berechnete Nettoenergiegehalt von Trockenschnitzeln betragt ca. 90% von dem der gequetschten Gerste.

Increases in hepatic CYP1A1 messenger RNA (mRNA) levels were quantitated, using a reverse-transcriptase–competitive-polymerase-chain-reaction assay, from juvenile chinook salmon following exposure to treated bleached-kraft mill effluent (BKME). Two tissue preservation techniques, alcohol fixation and freezing, were compared and both found to be valid, although absolute values obtained differed between the methods. The results of this study show that juvenile chinook respond with a dose-dependent induction of CYP1A1 mRNA to levels of treated BKME found under winter, low-flow conditions downstream of pulp mills in the Fraser River, British Columbia, Canada. The validation of alcohol fixation as a sampling technique for studies on mRNA levels improves the ease of field sampling and increases the feasibility of using CYP1A1 mRNA level as a bioindicator of exposure of fish to specific chemical contaminants.

SUMMARY Phosphate (P) was added to soil in solution. The soil was air-dried or freeze-dried and then incubated at a range of temperatures for periods of up to 110 d. The rate of the continuing reaction between the P and soil was measured using the null-point method, and by measuring the amount of desorption induced by filter paper impregnated with iron oxide (Pi test). The reaction between soil and P continued in both air-dried and freeze-dried soil, albeit more slowly than in moist soil. Freezing the soil, whether moist or dry, virtually stopped the reaction. These results are consistent with the hypothesis that the continuing reaction between P and soil involves a solid-state diffusive penetration of the soil particles by the sorbed P ions. They also indicate that the common practice of storing soil air-dry, even for short periods at low temperature, will not preserve the P status of the soil as at sampling. It was estimated that for a sample of soil which remained moist at 25°C for 100d after the addition of 335 μg P g−1 soil, before being sampled and stored air-dry at 4°C for 16 years, the measured Pi test value would be about 15 μg P g−1. This compares with 46 μg P g−1 which is the estimated Pi test value measured on the same day as sampling. When samples cannot be analysed for P status immediately following sampling, they should be stored at the lowest convenient temperature, preferably below 0°C.

The effects of incorporating sugar beet pulp with forage maize at ensiling on silage fermentation, effluent output and pollution potential of the effluent was investigated using 200-litre drum silos. A forage maize crop (Zea mais) was harvested on four different dates, generating four different stages of maturity [dry-matter (DM) content 154–235 g kg−1 DM], and molassed sugar beet pulp (MSBP) was added at five different rates (0, 2, 7, 13, 18 kg MSBP 100 kg−1 fresh maize crop). A total of fourteen treatments (each replicated three times) were evaluated. The chemical analysis of the maize silages and the mixtures produced showed that MSBP addition increased DM, ash, neutral cellulase gaminase digestibility (NCGD) and metabolizable energy (ME) contents of the mixture significantly (P

Larger fish species may not always be suitable for monitoring the response to industrial effluents because they are mobile and capable of extensive movement beyond effluent exposure areas. Spoonhead sculpin (Cottus ricei) was collected upstream and downstream of a large bleached-kraft pulp mill on the Athabasca River, Alberta, Canada, during fall and spring periods to determine whether small, sedentary fish species demonstrate responses reflecting local exposure conditions. During the fall sampling period, exposed fish were older and larger than upstream fish and showed increases in condition, gonad size, egg weight, liver weight, and hepatic mixed function oxygenase activity (7-ethoxyresorufin O-deethylase [EROD]). Sculpin collected from the opposite river bank, where exposure was reduced, showed condition factors, gonad size, egg weight, liver weight, and EROD activity that were not significantly different from reference sites or intermediate between reference and downstream values. In the spring after a prolonged overwinter exposure to higher effluent concentrations, exposed fish were larger, showed increased size-at-age, condition, liver weight, ovary size, and EROD activity. Far-field collections showed that most responses persisted downstream for at least 48 km. The general response of exposed spoonhead sculpin was consistent with a nutrient enrichment effect described in studies investigating water quality, algal growth, and benthos communities at this site but also may be related to reduced competition associated with the loss of older fish observed in the spring. The use of small species for sentinel monitoring provided a viable alternative to use of larger, more mobile species.

The H4IIE rat hepatoma bioassay was used to measure 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent concentrations (TECs) in livers of white sucker (Catostomus commersom) collected downstream from eight Ontario pulp mills and five reference sites. Subsamples of liver were also chemically analyzed for dioxins and furans. Bioassay-derived TECs were compared with TECs calculated from chemical residues using toxic equivalency factors (TEFs) specifically generated for the H4IIE cell line. This indicated that the bioassay-derived TECs could be accounted for largely by the additive effect of the dioxin and furan congeners. Seven of the eight examined mills had significantly higher TECs than the corresponding reference locations. The bioassay-derived TECs were highest at mills that used kraft pulping and chlorine bleaching. Although lower than the kraft mills, the thermomechanical (TMP) and sulfite mills also had higher TECs than the adjacent reference locations. The TECs were compared with hepatic 7-ethoxyresorufin-O-deethylase activity (EROD), as well as with concentrations of the plasma steroid hormones 17β-estradiol, 11-ketotestosterone, and testosterone. Significant correlations were found between EROD activity and TECs in both male and female white sucker. The correlation for males was stronger than that for females. Some of the variability in this relationship for females could be explained by a multivariate regression that added 17β-estradiol to the analysis; a strongly negative relationship between 17β-estradiol and EROD activity was superimposed on the positive EROD-TEC relationship. No significant correlations were found between TECs and 11-ketotestosterone in males, 17β-estradiol in females, and gonadosomatic indexes in either sex. There were significant negative correlations between TECs and testosterone in both sexes.

Twenty-one British Friesian dairy cows, in mid-lactation, were used in a seven-treatment, partially balanced change-over design experiment consisting of three periods each of 4 weeks' duration. Treatments involved offering grass silage either without a sugar-beet pulp (beet pulp) supplement (US) or supplemented with beet pulp at silage/beet pulp dry matter ratios of 80:20 (C40), 65:35 (C80) and 55:45 (C120), and offered in the form of a mixed ration. A further three treatments consisted of offering ensiled blends of silage and beet pulp, produced by mixing 40 (E40), 80 (E80) and 120 (E120)kg beet pulp t−1 of grass at ensiling. Silage was offered ad libitum on all treatments, with cows receiving 1kg d−1 of a concentrate supplement containing 470 g crude protein kg−1 fresh weight. Dry matter intakes increased with increasing level of beet pulp inclusion in the diet, irrespective of method of beet pulp inclusion in the diet. Similarly, milk fat + protein yields increased with increasing level of beet pulp offered. However, when comparisons were made between the two methods of beet pulp inclusion in the diet with beet pulp requirements equivalent to those obtained in treatments C40, C80 and C120, namely 2·28, 4·53 and 6·21 kg d−1, offering beet pulp as a supplement to an untreated silage resulted in fat + protein yields of 32 (s.e.d. 9·8), 53 (s.e.d. 19·5) and 81 (s.e.d. 21·3)gd−1 greater than would have been achieved had equivalent quantities of beet pulp been included at ensiling as part of an ensiled blend. This effect can be attributed to the higher metabolizable energy intakes with the control silage supplemented with beet pulp at feeding, a consequence of the loss of nutrients from the beet pulp fraction during ensiling, in the case of treatments E40, E80 and E120. However, when account is taken of differences in the efficiency of recovery of edible silage dry matter between ensilage systems and differences in forage dry-matter intake between treatments, overall efficiency of feed use was not significantly different between the two systems of beet pulp inclusion in the diet.

First-harvest direct-cut, double-chopped grass (190 and 164g DMkg−1 in Experiments 1 and 2 resptectively) was ensiled without an additive or, in Experiment 1, with 30 kg t−1 grass of an absorbent additive based on sugar beet pulp (Sweet ‘n’ Dry) or with 3·441 t−1 grass of formic acid and, in Experiment 2, with 30, 50 and 70 kg t−1 grass of Sweet ‘n’ Dry or with 50kg t−1 grass of unmolassed sugar beet pulp. The preservation and nutritive value of the silage, in-silo losses (including silage effluent production), silage intake and animal performance of adult and growing cattle were examined. In Experiment 1 all three silages were well preserved, although the formic acid-treated silage displayed significantly lower pH, ammonia nitrogen (NH3N) [g kg−1 total nitrogen (TN)] and volatile fatty acids (VFAs) than the other two silages. In Experiment 2 absorbent-treated silages displayed significantly lower pH, buffer capacity (Bc), NH3N (gkg−1 TN), CP, modified acid detergent fibre (MADF) and VFAs than untreated silage. Treatment of grass with the absorbent additives at ensiling resulted in reduced effluent production. In Experiment 1 each kilogram of Sweet ‘n’ Dry retained approximately 11 effluent, and in Experiment 2 silages made with Sweet ‘n’ Dry applied at 70kgt−1 and sugar beet pulp applied at 50 kg t−1 produced similar volumes of effluent and each kilogram of absorbent retained 1·0 and 1·31 of effluent respectively. In Experiment 1 sixty beef cattle [mean initial live weight (LW) 460 kg] were grouped according to LW and allocated to treatment at random. For untreated silage (unsupplemented or with 1 or 2 kg supplement head−1 day−1), absorbent-treated silage (unsupplemented or with 1 or 2 kg supplement head−1 day−1) and formic acid-treated silage (1 kg supplement head−1 day−1) the daily silage DM intakes were 6·12, 6·21, 6·40, 7·65, 7·45, 7·11 and 7·85 (s.e. 0·280) kg respectively, the daily liveweight gains were 0·22, 0·56, 0·81, 0·59, 0·74, 0·81 and 0·75 (s.e. 0·071) kg respectively and daily carcass gains were 0·31, 0·47, 0·67, 0·47, 0·61, 0·70 and 0·57 (s.e. 0·043) kg respectively throughout a 75-day feeding period. In Experiment 2, fifty-six growing cattle (mean initial weight 312 kg) were grouped according to LW and allocated to treatment at random. For untreated silage (unsupplemented or with 1·5 kg Sweet ‘n’ Dry or 1·5 kg commercial concentrates head−1 day−1), silage treated with Sweet ‘n’ Dry at 30, 50 and 70 kg t−1 grass and silage treated with 50kg sugar beet pulp t−1 grass the daily silage DM intakes were 5·46, 5·28, 5·33, 6·21, 6·27, 6·60 and 6·62 (s.e. 0·154) kg respectively and daily liveweight gains were 0·39, 0·75, 0·81, 0·63, 0·76, 0·94 and 1·75 (s.e. 0·052) kg respectively throughout a 122-day feeding period. In this experiment 360g kg−1 more absorbent was required when it was included at ensiling rather than offered as a supplement to untreated silage to achieve the same individual animal performance.

Progesterone, androstenedione, and androstadienedione were previously identified in the water and sediment of the Fenholloway River (Taylor County, FL, USA), a river that contains populations of masculinized female mosquitofish downstream of a paper mill, at levels higher than those in the nearby Spring Creek. Plant sterols, such as beta-sitosterol in mill effluent derived from pine tree pulp, were suggested to be metabolized by bacteria to progesterone and androgens to account for the masculinization phenomenon. The current study made use of standard solid-phase methanol extraction procedures, high-performance liquid chromatography, liquid chromatography-mass spectrometry, and a cell-based, androgen-receptor transcription assay to determine naturally occurring progesterone levels in mature pine trees. Progesterone concentrations in the loblolly pine (Pinus taeda L.) were 49.34 +/- 4.1 nmol/g dry mature wood (15.5 +/- 1.29 microg/g), 12.26 +/- 1.78 nmol/g pine needles (3.85 +/- 0.56 microg/g), and 3.81 +/- 0.36 nmol/g pine bark (1.19 +/- 0.11 mug/g). The results suggest that naturally occurring progesterone from pine wood pulp contributes to increased progesterone levels downstream of paper mill effluent discharges and may serve as the natural steroid precursor for environmental androgen production that causes masculinization of female mosquitofish.

Ninety-six h LC50 values for 1,1,3-trichloro-, 1,1,3,3-tetrachloro-, pentachloro- and hexachloroacetone for juvenile rainbow trout (Salmo gairdneri) were 2.3, 11.0, 25.0 and >25 mg/L, respectively. Levels in chlorination-stage effluents from eight pulp mills sampled across Canada were as follows: trichloro

First instar Heliothis zea larvae tended to feed on the leaves of snap beans, but later instars preferred to burrow in the pods. Fifth instars offered only leaves grew poorly because they ate them in small quantities, presumably because of deterrency. The utilization efficiency and growth of fifth instars fed pulp was slightly but significantly inferior to that of seed-fed larvae but was greatly superior to that of leaf-fed larvae. Since the dry matter content of pulp is less than one-third that of seeds, larvae allowed to eat only pulp had abnormally large fresh weight intakes and devoted about three times as much time to feeding as did seed-fed larvae. Larvae offered a mix of seeds and pulp ate both and had a total fresh weight food intake somewhat greater than that of seed-fed larvae but much less than that of pulp-fed larvae. Eating both seeds and pulp offers no obvious nutritional advantage but presumably offers a significant ecological advantage. It is argued that the number of foraging trips a larva must make to discover pods is minimized by feeding on a mix, thus reducing exposure to mortality factors such as predation.

Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were measured in white sucker liver samples from seven pulp and paper mill sites, and three reference sites in Ontario. The mills included five bleached-kraft mills, with and without secondary treatment, and two sulfite-mechanical mills. 2,3,7,8-T[sub 4]CDD and 2,3,7,8-T[sub 4]CDF were the dominant congeners detected in both liver and fillet samples at all of the pulp and paper mill sites, with mean 2,3,7,8-T[sub 4]CDD toxic equivalent concentrations (TEQs) as high as 124 pg g[sup [minus]1] in liver tissue. concentrations of PCDDs/PCDFs in liver tissues were severalfold higher than in fillet tissue, but this difference can be accounted for by lipid normalization. Biological information, including liver weight, gonad weight, MFO activity (ethoxyresorufin-O-deethylase, EROD), and plasma sex steroids, was measured on individual fish. There was no relationship between TEQs and condition factor, gonadosomatic index, liver somatic index, or circulating plasma 11-ketotestosterone. A weak negative correlation was observed between circulating plasma testosterone and TEQs. Although there was a positive correlation between MFO activity (EROD) and TEQ, one site with very low chlorine used and low TEQs and EROD activity similar to levels observed at more contaminated sites. This finding, along with recent observations that MFO activity ismore » rapidly cleared in pulp-mill-exposed fish, casts doubt on an exclusive causal relationship between MFO activity and PCDDs/PCDFs in these sites.« less

Reproductive effects have been recorded in wild fish in waters receiving pulp mill effluent (PME) since the mid to late 1980s. Laboratory assays with fathead minnow (FHM; Pimephales promelas) have been developed to better understand fish responses to PME. However, observations from laboratory studies have been variable, making it difficult to establish cause/effect relationships. A lack of environmental relevance in these laboratory studies may have contributed to the variability observed. The objectives of the present study were, first, to determine the effects of bleached kraft PME (BKME) on FHM under environmentally realistic conditions (i.e., ambient water and effluent quality) and, second, to determine the suitability of pair-breeding FHM to better link BKME-induced changes in indicators at the biochemical, individual, and population levels. A mobile bioassay trailer was situated on-site at a bleached kraft mill for 60 d, allowing supply of both ambient water (Lake Superior, Canada) and final BKME. The reproductive output of FHM was initially assessed for 21 d to obtain baseline data pre-exposure. At the end of the pre-exposure period, selected breeding pairs were exposed to final BKME (100% v/v and 1% v/v) for 21 d. Results demonstrated a stimulatory response pattern at 1% BKME (e.g., increased egg production) compared to control. In the 100% treatment, spawning events were reduced and fewer eggs were produced during the first two weeks of exposure. Exposure to 100% (v/v) BKME also resulted in ovipositor development in males and development of male secondary sex characteristics in females. Obtaining pre-exposure data and use of pair-breeding FHM in this assay gave a sensitive indication of effluent effects and allowed accurate comparisons of endpoints to be made.

Fish, Cyprinus carpio and Channa punctatus in four sizes (6.0 ± 1.2; 12.5 ± 1.6; 20.6 ± 1.5 and 28.0 ± 1.8 cm in total length) were exposed to industrial effluents from the Sangam Dyeing Factory (Ludhiana), the Sterling Steel and ABC Paper Mills (Hoshiarpur) to evaluate the acute toxicity of these effluents at different fish sizes. Results reveal that the toxicity of industrial effluents decreased with the increased fish size from 6.0 ± 1.2 to 20.6 ± 1.5 cm in length. However, for specimens of the size of 28.0 ± 1.6 cm and more, the toxicity of the effluents increased with an increase in fish size. On the basis of the relative toxicity to fish, effluent from the Sterling Steel Mill was found to be highly toxic to fish and effluent from the Dyeing Factory least toxic except for the fish of 6.0 ± 1.2 cm at which dyeing factory effluent was most toxic and ABC paper mill effluent the least toxic.

The method of preservation of forage tissue may influence the quality and quantity of the product. Oven drying with hot air is widely used; however, enzyme activity and respiration are stimulated during the moisture reduction process. Criterion for selecting efficient drying conditions, such as sample density, kind of container (cloth or paper), and size of container were investigated using alfalfa (Medicago sativa L.) herbage. The dry matter, total nonstructural carbohydrate (TNC), starch, reducing sugar, and nonreducing sugar percentages were related to drying rate. Drying rate was linear until 80% dry weight was reached. Conditions requiring no more than 15 hours to reach 80% dry wt (density of 12 g dry wt per liter for paper sacks) were needed to hold loss within limits of experimental error for estimation of dry weight percentage. The TNC in all oven-dried samples was less than in freeze-dried tissue; however, data from cloth bags showed less loss and carbohydrate interconversion than paper sacks. Conditions requiring no more than 8 hours to reach 80% dry wt (density of 7 g per liter for paper sack) were required for sufficiently rapid drying to limit loss and interconversions of nonstructural carbohydrates within limits of experimental error. About twice this density was acceptable if cloth bags were used since the drying tune was reduced by about one-half with cloth as compared to paper containers that had equal densities. Acceptable bulk densities will differ with efficiency of the drying equipment, but time needed for drying to 80% dry wt should not exceed these limits.

SUMMARY Water loss from cut grass was studied to determine factors limiting the drying process. An apparatus, used to measure water loss at 28±1°C from blotting paper and from leaves and stem internodes of cocksfoot, consisted of four channels in which air speed was controlled at 25–80 cm s-1 and relative humidity at 7–68%. The maximum rate of water loss from wet blotting paper was 10500 mg water dm-2 h-1 but from leaves and stem internodes supplied with water it was less than 250 mg dm-2 h-1. The rate of loss from both plant specimens and blotting paper was linearly related to the vapour pressure differences between the specimen and the surrounding air but was not increased when air speed was changed from 40 to 80 cm s-1. Grass specimens supplied with water had lower rates of water loss than wet blotting paper because of tissue resistances which were calculated for (a) untreated leaf and stem specimens, (b) rubbed leaves, (c) cut leaves, (d) leaves exposed to steam for 60 s. Treatments (b)-(d) greatly reduced tissue resistances. The rates of drying of leaves and stem internodes not supplied with water changed only slightly in response to faster air speeds but were significantly increased by treatments (b), (c), (cs) (split stems), (d) and (e) (exposure to petroleum vapour for 60 s). The most effective treatments trebled the drying rates of leaves and increased the drying rates of stem internodes by 10 times. Reductions in relative humidity had little effect on drying rate following treatments (a), (b), (c) and (d), but when treatments (cs) and (e) were given, additional significant increases in drying rates were obtained when the relative humidity was reduced. Grass specimens given the most effective treatments and dried under the most favourable conditions did not utilize the full drying capacity of the environment, for the rates of water loss from these specimens were at least three times lower than those from wet blotting paper. The results indicate that high rates of drying could be achieved at 28 oC or similar temperatures if practical treatments were developed to remove or greatly reduce the high resistance to water loss in cut grass.

While one of us (E. B. C., '31) was investigating the action of ultraviolet rays on the embryos of Lintax flavus Linnaeus, it was noticed that some batches of eggs were so dehydrated that they were wrinkled or had depressions in them. This condition prevailed if the eggs were laid in a dry or moderately damp receptacle. These eggs, however, would hatch if placed in a moist container. Khalil ('22) found that Planorbis corners were quite susceptible to drying, being killed in five hours when in a jelly-like mass. Adolph and Adolph ('25) placed Lumbricus terrestris in a 0.I36 M solution of sodium chloride for twenty hours and found that the worms would recover after a 35 per cent loss in weight. Jackson ('26) also, working on Lumbricus terrestris. found that they would live, after losing 43 per cent of their original weight in four to five hours, when placed on dry filter paper. Jackson found that they would die if they lost 50 to 6o per cent of their weight. Since the eggs of Limnax flavus Linnaeus hatched after being dehydrated enough to show a definite depression, we decided to perform a series of experiments to determine the maximum loss in weight which the young would survive and still be able to hatch. The eggs are fastened together by means of a membrane and thus all are laid at once. The slugs do not move while laying; hence the eggs become superimposed and are able to retain their moisture for a longer period than single eggs. The eggs varied considerably in weight: the maximum being 97.49 milligrams and the minimum being 5I.i6 milligrams. The average weight for I,200 eggs was found to be 78.7I milligrams. The eggs are elliptical in shape, the average diameter being about 0.5 centimeter and the average length being about 0.75 centimeter. They are covered with a rather tough membrane, which allows them to be moved on dry filter paper without being ruptured. A vitilline membrane surrounds the embryo, and this membrane is surrounded by a semi-fluid gelatinous mass, which resembles egg white. These experiments were conducted at room temperature (20 to 300 C.). The slug eggs, containing embryos from one to twenty-two days old, were weighed and subjected to dehydration. The eggs were placed on clean dry filter paper, the drying process lasting from two to seven hours. The eggs were weighed at the end of definite periods and placed in Petri dishes on moist filter paper. The weights given in this paper are averages in all cases.

Fish collected from the receiving areas of 12 Canadian pulp mills were examined, including sites receiving effluent from kraft mills using chlorine as well as sulfite mills. Field collections included sampling of receiving water for chemistry and toxicity testing, and sampling of local fish for organ weights, hepatic MFO (ethoxyresorufin-O-deethylase, EROD) activity, plasma steroid levels, and levels of liver dioxins. The main objectives of this study were to determine whether the discharge of effluent from pulp mills to sites other than Jackfish Bay was associated with physiological or biochemical disruptions in wild fish, whether there was any correlation between waste treatment and the presence of biological responses in wild fish, and whether there was any association between the use of chlorine as a bleaching agent and these responses. Although white sucker collected near bleached-kraft mills exhibited the highest EROD induction and dioxin levels, elevated enzyme activity was observed in fish from sites that did not use chlorine, and depressions in plasma sex steroid levels was not correlated with the level of EROD activity. The absence of chlorine bleaching or the presence of secondary treatment did not eliminate responses in fish, including decreased circulating levels of sex steroids, decreased gonadal size, and increased liver size. This survey has shown that (a) induction of hepatic EROD enzymes and depressions of plasma sex steroid levels during gonadal growth are found downstream of several pulp mills; (b) these changes are seen at some mills without chlorine bleaching and at mills that have secondary treatment; (c) substantial dilutions of nontoxic effluent do not appear to remove these responses; (d) the dominant factor determining the presence or absence of responses appeared to be dilution level; and (e) lab toxicity tests on invertebrates, rainbow trout, and fathead minnows could not predict the presence of these responses in wild fish.