scholarly journals Biodiversity and springtime patterns of egg production and development for parasites of the Chisana Caribou herd, Yukon Territory, Canada

Rangifer ◽  
2009 ◽  
Vol 29 (1) ◽  
pp. 25-37 ◽  
Author(s):  
Bryanne Hoar ◽  
Michelle Oakley ◽  
Rick Farnell ◽  
Susan Kutz
Keyword(s):  
Egg Production ◽  
Sampling Period ◽  
Early Summer ◽  
Yukon Territory ◽  
Parasite Development ◽  
Eimeria Spp ◽  
Larval Production ◽  
Natural Range ◽  
Eggs And Larvae ◽  
Over Time

We investigated the biodiversity and springtime patterns of parasite egg/oocyst and larval production from feces and parasite development in the environment for the Chisana caribou herd in the southwest Yukon Territory, Canada from 29 March to 14 June 2006. Fecal samples from 50 adult cows that were housed in a temporary enclosure within the herd’s natural range at Boundary Lake, Yukon Territory were collected and analyzed during 5 sampling periods. A minimum of 6 parasite genera were recovered: eggs of Trichostrongylidae species (most likely Ostertagia gruehneri and Teladorsagia boreoarcticus), Marshallagia sp., Anoplocephalidae cestodes, and Skrjabinema sp.; oocysts of Eimeria spp.; and dorsal-spined first-stage protostrongylid larvae, including Parelaphostrongylus andersoni. Prevalence of Trichostrongylidae spp. eggs in fresh fecals was at or near 100% throughout the sampling period, however, the median intensity increased significantly from 8 to 34 eggs per gram (epg) at the peak of calving and then decreased to 12 epg 2 weeks post-calving (P = 2.83e-07). Three plots of feces collected from these animals were established outside of the enclosure on 4 May 2006 and monitored every 10 days to investigate patterns of parasite development under natural conditions. The total number of Trichostrongylidae spp. (eggs + larvae) in fecal plots did not change over time, but as the number of larvae increased, egg counts decreased. The presence of other parasite species in the fecal plots remained constant over time. This study is the first to document the parasite diversity for the Chisana caribou herd and to exam¬ine the development and survival of eggs and larvae in feces throughout the spring and early summer. Abstract in Norwegian / Sammendrag: Parasitters artssammensetning og forløp av eggproduksjon og parasittutvikling om våren hos Chisanavillreinen i Yukon, Canada I en periode fra 29. mars til 14. juni 2006 tok vi prøver fra reinmøkk og under¬søkte artsammensetning, egg/oocysteproduksjon og parasittutvikling i et område sørvest i Yukon, Canada, der Chisana caribou’en holder til. Møkkprøver fra 50 voksne simler, holdt i en midlertidig inngjerding i det naturlige beiteområdet ved Bondary Lake, ble samlet og analysert i løpet av fem prøveperioder. Parasitter fra minst seks slekter ble funnet: materialet omfattet egg av Trichostrongylidae-arter (mest sannsynlig Ostertagia gruehneri og Teledorsagia boreoarcti¬cus), Marshallagia-art, Anaplocephalidae-bendelmark og Skrjabinema-art, oocyster av Eimeria-arter, og ryggpiggete førstestadiums Protostrongylidae-larver, bl.a. av Parelaphostrongylus andersoni. I ferske møkkprøver var prosentvis tilstedeværelse av Trichostrongylidae-egg nesten 100 % gjennom prøveperioden, men median intensitet (parasittmengde) økte statistisk signifikant fra 8 til 34 egg per gram under kalvingens mest intense periode og avtok til 12 egg per gram to uker etter kalving. Møkk fra forsøkssimlene ble den 4. mai plassert i tre felt utenfor området der simlene ble holdt inngjerdet, og undersøkt hver tiende dag for å følge parasittutviklingen under naturlige betingelser. Det totale antall av egg + larver Trichostrongylidae i feltene forandret seg ikke; larvemengden økte samtidig som eggmengden avtok. Tilstedeværelsen av andre parasitter i feltene forble også konstant over tid. Vår studie er den første til å dokumentere parasittdiversiteten i Chisanavillreinen og å undersøke utviklingen og overlevelsen av egg og larver gjennom vår og tidlig sommer.

Toward a blood-free diet for Anopheles darlingi (Diptera: Culicidae)

2019 ◽  
Vol 57 (3) ◽  
pp. 947-951
Author(s):  
Glaucilene da Silva Costa ◽  
Moreno Magalhães Souza Rodrigues ◽  
Alexandre de Almeida e Silva
Keyword(s):  
Egg Production ◽  
Laboratory Experiments ◽  
Artificial Diet ◽  
Ethical Issues ◽  
Sugar Solution ◽  
Anopheles Darlingi ◽  
Larval Production ◽  
The Mean ◽  
Protein Rich ◽  
Eggs And Larvae

Abstract Due to ethical issues associated with the use of blood for mosquito laboratory experiments, an artificial diet that supports the production of eggs and larvae is highly desirable. We report the development of an artificial diet using direct feeding on protein-rich sugar solution (PRSS) as an alternative to whole blood and evaluated its effects on several biologic parameters of Anopheles darlingi (Root). Field-collected females were fed with different PRSSs containing bovine serum albumin (BSA) at 200 and 400 mg/ml with or without supplemental salts. Engorged mosquitoes were monitored for survival to oviposition, before being forced to oviposit. The proportion ovipositing, number of eggs, and number of larvae were recorded for each treatment. Mosquitoes promptly engorged on PRSSs. The mean proportion of mosquitoes fed with PRSS that survived to oviposition did not differ statistically from that of blood-fed ones. The oviposition proportion of females fed with PRSS at 200 mg/ml was similar to that of blood-fed mosquitoes, whereas mean egg production was lower for most PRSS-fed females, except for those fed with BSA at 400 mg/ml. However, the mean larval production of PRSS-fed mosquitoes was significantly lower than that of blood-fed females. Although feeding An. darlingi on simple PRSS triggered oogenesis and embryogenesis, our results highlight the need for additional nutrients to increase the number of larvae to improve overall reproduction potential.

Transport and development of eggs and larvae of Atlantic cod, Gadus morhua, in relation to spawning time and location in coastal Newfoundland

2000 ◽  
Vol 57 (9) ◽  
pp. 1761-1772 ◽  
Author(s):  
Ian R Bradbury ◽  
Paul V.R. Snelgrove ◽  
Sandra Fraser
Keyword(s):  
Egg Production ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Early Spring ◽  
Egg Hatching ◽  
Larval Size ◽  
Order Of Magnitude ◽  
Larval Production ◽  
Placentia Bay ◽  
Eggs And Larvae

We provide evidence that variation in location and timing of spawning of Atlantic cod, Gadus morhua, has a major impact on occurrence, distribution, and development of eggs and larvae in a large embayment on the south coast of Newfoundland. Atlantic cod egg densities, measured with a series of ichthyoplankton surveys in Placentia Bay during the spawning and postspawning seasons of 1997 and 1998, were highest during the early spring of both years and decreased through the spring and summer. Egg development stages and larval size suggest that eggs and larvae were released from spawning locations within the bay and developed as they were transported in cyclonic flow from the southeast and around the bay towards the southwest, where late-stage eggs and larvae were found to be most abundant. Although egg densities were generally lower in 1998, late-season egg production during the summer of 1998 was elevated in relation to 1997, providing a possible explanation for the observation that larval total densities were more than an order of magnitude higher in 1998 than in 1997. In terms of larval production, late spawners may be particularly important to successful egg hatching in the coastal waters of Newfoundland.

scholarly journals Variation over Time of Length–Weight Relationships and Condition Factors for Four Exotic Fish Species from a Restored Shallow Lake in NE Iberian Peninsula

Fishes ◽  
2020 ◽  
Vol 5 (1) ◽  
pp. 7
Author(s):  
Jorge Rubén Sánchez-González ◽  
Amadeo Arbonés ◽  
Frederic Casals
Keyword(s):  
Shallow Lake ◽  
Fish Community ◽  
Community Dynamics ◽  
Early Summer ◽  
Northern Spain ◽  
Exotic Fish ◽  
Fish Samples ◽  
Natural Range ◽  
Ne Iberian Peninsula ◽  
Over Time

Length–weight relationships (LWRs), condition factors, and their variation over time were analyzed for four exotic freshwater fish (bleak, common carp, pikeperch, and roach) in the Estany d’Ivars i Vila-sana shallow lake in Catalonia, Northern Spain. Fish samples were collected twice a year (early summer and autumn), between 2008 and 2016, by using between three and five multi-mesh nylon gillnets. This study provides novel information about four common exotic fishes outside of their natural range and within the context of a restored shallow lake, where the ichthyologic community is evolving in concordance with the ecosystem conditions and the fish community dynamics.

Modelling the egg components and internal cycle length of laying hens

2019 ◽  
Vol 59 (3) ◽  
pp. 420 ◽  
Author(s):  
H. C. P. Bendezu ◽  
N. K. Sakomura ◽  
E. B. Malheiros ◽  
R. M. Gous ◽  
N. T. Ferreira ◽  
...  
Keyword(s):  
Cycle Length ◽  
Egg Production ◽  
Laying Hens ◽  
Experimental Period ◽  
Experimental Unit ◽  
Egg Weight ◽  
Cycle Lengths ◽  
Predicted Values ◽  
Egg Components ◽  
Over Time

A model that can estimate the changes that occur to the composition of egg components over time is an important tool for the nutritionists, since it can provide information about the nutrients required by a laying hen to achieve her potential egg output. In this context, the present study was aimed to model the potential egg production of laying hens during the egg-production period. One hundred and twenty Hy-Line W36 and ISA-Brown layers were used from 18 to 60 weeks of age, with each bird being an experimental unit. The birds were housed in individual cages during the experimental period. Egg production (%), egg weight (g) and the weight of egg components were recorded for each bird. The data were used to calculate the parameters of equations for predicting the weights of yolk, albumen and shell, and for predicting internal cycle length. The predicted results were evaluated by regressing residual (observed minus predicted) values of the predicted values centred of their average value. The equations for predicting mean yolk weight with age are for Hy-Line W36 (y1) and ISA-Brown (y2) respectively. Albumen and shell weights for Hy-Line W36 were described by the equations 15.07 × (yolk weight)0.37 and 0.70 × (yolk + albumen weight)0.50 respectively, and for ISA-Brown, 21.99 × (yolk weight)0.24 and 1.60 × (yolk + albumen weight)0.34 respectively. The average internal cycle length over time for Hy-Line W36 (ICL1) is described by the model 22.95 + 5.24 × (0.962t) + 0.02 × t and for ISA-Brown by 24.01 + 10.29 × (0.94t) + 0.004 × t, where t is the age at first egg (days). The assessment of the results indicated that the equations for predicting egg weight were more accurate for Hy-Line W36 but less precise for both strains, whereas the equation models for predicting the internal cycle lengths were more accurate and precise for ISA-Browns. The models could predict the potential weight of egg components and the rate of laying associated with the internal cycle lengths, and, on the basis of this information, it is possible to improve the nutrient requirement estimated.

scholarly journals Microbial Utilisation of Aboveground Litter-Derived Organic Carbon Within a Sandy Dystric Cambisol Profile

2021 ◽  
Vol 1 ◽  
Author(s):  
Sebastian Preusser ◽  
Patrick Liebmann ◽  
Andres Stucke ◽  
Johannes Wirsching ◽  
Karolin Müller ◽  
...  
Keyword(s):  
Microbial Biomass ◽  
Organic Carbon ◽  
Soil Depth ◽  
Sampling Period ◽  
Beech Forest ◽  
Stable Isotope Labelling ◽  
C Stocks ◽  
Microbial Groups ◽  
Aboveground Litter ◽  
Over Time

Litter-derived dissolved organic carbon (DOC) is considered to be a major source of stabilised C in soil. Here we investigated the microbial utilisation of litter-derived DOC within an entire soil profile using a stable isotope labelling experiment in a temperate beech forest. The natural litter layer of a Dystric Cambisol was replaced by 13C enriched litter within three areas of each 6.57 m−2 for 22 months and then replaced again by natural litter (switching-off the 13C input). Samples were taken continuously from 0 to 180 cm depths directly after the replacement of the labelled litter, and 6 and 18 months thereafter. We followed the pulse of 13C derived from aboveground litter into soil microorganisms through depth and over time by analysing 13C incorporation into microbial biomass and phospholipid fatty acids. Throughout the sampling period, most of the litter-derived microbial C was found in the top cm of the profile and only minor quantities were translocated to deeper soil. The microbial 13C stocks below 30 cm soil depth at the different samplings accounted constantly for only 6–12% of the respective microbial 13C stocks of the entire profile. The peak in proportional enrichment of 13C in subsoil microorganisms moved from upper (≤ 80 cm soil depth) to lower subsoil (80–160 cm soil depth) within a period of 6 months after switch-off, and nearly disappeared in microbial biomass after 18 months (< 1%), indicating little long-term utilisation of litter-derived C by subsoil microorganisms. Among the different microbial groups, a higher maximum proportion of litter-derived C was found in fungi (up to 6%) than in bacteria (2%), indicating greater fungal than bacterial dependency on litter-derived C in subsoil. However, in contrast to topsoil, fungi in subsoil had only a temporarily restricted increase in litter C incorporation, while in the Gram-positive bacteria, the C incorporation in subsoil raised moderately over time increasingly contributing to the group-specific C stock of the entire profile (up to 9%). Overall, this study demonstrated that microorganisms in topsoil of a Dystric Cambisol process most of the recently deposited aboveground litter C, while microbial litter-derived C assimilation in subsoil is low.

scholarly journals Experimental infections of muskoxen (Ovibos moschatus) and domestic sheep with Umingmakstrongylus pallikuukensis (Nematoda: Protostrongylidae): parasite development, population structure, and pathology

1999 ◽  
Vol 77 (10) ◽  
pp. 1562-1572 ◽  
Author(s):  
S J Kutz ◽  
E P Hoberg ◽  
L Polley
Keyword(s):  
Parasite Development ◽  
Domestic Sheep ◽  
Lung Pathology ◽  
Experimental Conditions ◽  
Ovibos Moschatus ◽  
Lung Cysts ◽  
Pulmonary Cysts ◽  
Third Stage ◽  
Larval Production ◽  
Umingmakstrongylus Pallikuukensis

Three captive muskoxen (Ovibos moschatus) were successfully infected with third-stage larvae of Umingmakstrongylus pallikuukensis digested or emerged from the slugs Deroceras reticulatum and D. laeve, for the first time completing the life cycle of this parasite under experimental conditions. The course of parasite development and patency was followed for 26 months post infection (p.i.) using fecal examinations and radiography. The prepatent periods in two of the muskoxen were 91 and 95 days and the patent period in one extended for 23 months. Larval production peaked 13-14 months p.i. On postmortem of two of the muskoxen at months 14 and 26 p.i., adult parasites were found only within pulmonary cysts and cysts were randomly distributed between left and right lungs. Cyst dimensions were positively correlated with the number of adult parasites they contained. On postmortem of the third muskox at day 97 p.i., not all adult parasites were within typical cysts; two were found free in interlobular septa. First-stage larvae were recovered from lung cysts of this animal but not from feces. Lung pathology in all three muskoxen appeared localized and associated with the adult nematodes. Infection of two sheep with third-stage larvae of U. pallikuukensis did not result in parasite establishment.

Ichthyoplankton of the St. Lawrence Estuary: Composition, Distribution, and Abundance

1978 ◽  
Vol 35 (12) ◽  
pp. 1518-1531 ◽  
Author(s):  
Kenneth W. Able
Keyword(s):  
Key Words ◽  
Sampling Period ◽  
Nursery Area ◽  
Composition Distribution ◽  
Lawrence Estuary ◽  
Demersal Eggs ◽  
June July ◽  
Saguenay River ◽  
St Lawrence Estuary ◽  
Eggs And Larvae

The composition, distribution, and abundance of ichthyoplankton in the St. Lawrence estuary, including adjacent portions of the Saguenay River and the northwestern Gulf of St. Lawrence, were investigated during June–July 1973, June–October 1974, and May–September 1975. The eggs and larvae of 25 species from 14 families (principally osmerids, gadids, cottids, cyclopterids, and pleuronectids) were represented. The larvae, in every year, were almost exclusively forms with demersal eggs. Larvae were consistently more abundant in the upper estuary during every sampling period due to its use as a major spawning and nursery area for several species. Both eggs and larvae were most abundant in June and July. Probable spawning times, areas, and growth of larvae are discussed for selected species. Key words: ichthyoplankton, St. Lawrence estuary, distribution, larvae, osmerids, gadids, cottids, cyclopterids, pleuronectids

scholarly journals Oviposition by Schistosoma mansoni during in vitro cultivation

1996 ◽  
Vol 38 (6) ◽  
pp. 423-426 ◽  
Author(s):  
Leo Roberto Barth ◽  
Ana Paula Morais Fernandes ◽  
Vanderlei Rodrigues
Keyword(s):  
Schistosoma Mansoni ◽  
Egg Production ◽  
Culture Medium ◽  
Parasite Development ◽  
In Vitro Cultivation ◽  
Progressive Reduction ◽  
Maximum Period ◽  
Medium Time ◽  
Kinetics Of

Observation of Schistosoma mansoni oviposition during in vitro culture of adult worms for a maximum period of 10 days showed three well distinct phases in the kinetics of oviposition: an initial phase with low egg production, a period of maximum oviposition and finally a progressive reduction in the number of eggs during the late phases of culture. The kinetics of oviposition and the number of eggs laid by the parasites are influenced by the number of worm pairs per amount of RPMI 1640 medium, time of parasite development in the vertebrate host and type of serum utilized in the culture medium.

Effect of geographic variation and jack pine introgression on disease and insect resistance in lodgepole pine

1996 ◽  
Vol 26 (5) ◽  
pp. 711-726 ◽  
Author(s):  
Harry X. Wu ◽  
Cheng C. Ying ◽  
John A. Muir
Keyword(s):  
British Columbia ◽  
Lodgepole Pine ◽  
Pest Resistance ◽  
Strong Relationship ◽  
Jack Pine ◽  
Yukon Territory ◽  
Geographic Patterns ◽  
Effective Selection ◽  
Pest Incidence ◽  
Natural Range

Incidence of western gall rust (Endocronartiumharknessii (J.P. Moore) Y. Hiratsuka), stalactiform blister rust (Cronartiumcoleosporioides Arth.), needle cast (Lophodermellaconcolor (Dearn.) Darker), and sequoia pitch moth (Synanthedonsequoiae (Hy. Edwards) (Lepidoptera: Sesiidae)) attacks were investigated in a lodgepole pine (Pinuscontorta Dougl. ex Loud, van latifolia Engelm.) provenance–family test plantation located at Red Rock Tree Improvement Station, Prince George, British Columbia. This plantation contains 778 wind-pollinated families from 53 provenances in British Columbia, Alberta, and the Yukon Territory. Pest incidence was assessed in 1993 when the plantation was 21 years old. Provenance had a significant effect on resistance to the four disease and insect attacks. Regression models using latitude, longitude, and elevation as predictors accounted for 38% to 80% of the provenance variation in pest incidence. Geographic patterns of genetic variation in pest resistance essentially followed longitudinal and elevational clines. The most interesting finding is the strong relationship between pest incidence and provenance distance to the western limit of the natural range of jack pine (Pinusbanksiana Lamb,): the closer a lodgepole pine provenance is to the edge of jack pine distribution, the higher is its resistance to the pests. We hypothesize that jack pine introgression may have played a significant role in the evolution of pest defense in lodgepole pine. Effective selection and breeding for pest resistance in lodgepole pine may have to look beyond the intraspecific gene pool.

Effect of dietary nutrient concentration on the performance of hens beginning lay in early summer

1986 ◽  
Vol 26 (4) ◽  
pp. 405 ◽  
Author(s):  
AS Pell ◽  
RW Polkinghorne
Keyword(s):  
Egg Production ◽  
Nutrient Concentration ◽  
Early Summer ◽  
Nutrient Concentrations ◽  
Egg Mass ◽  
Meat Meal ◽  
High Nutrient ◽  
Dietary Nutrient ◽  
Metabolisable Energy ◽  
High Nutrient Concentration

Hens of 2 laying strains were fed ad libitum from 20 to 72 weeks of age on 3 diets of different nutrient concentration. The start of lay coincided with the onset of the hot summer. During summer, birds on the diet with high nutrient concentration (HNC, 19% protein, 12.6 MJ metabolisable energy (ME)/kg) had significantly higher intakes of ME (3% higher) and other nutrients than did those on the diets of medium (MNC, 18% protein, 11.7 MJ ME/kg) and low (LNC, 16% protein, 11.4 MJ ME/kg) nutrient concentration. Egg weight. egg mass and feed efficiency were greater on the HNC diet than on the MNC and LNC diets. Birds on the HNC diet produced more eggs (10% more) than those on the LNC diet. Over the cooler periods, feed intakes were inversely related to energy level, with no dietary effects on egg production. It is concluded that grain- and meat meal-based diets of low nutrient concentrations are unlikely to support maximum performance in early lay in hot conditions and that increased dietary nutrient concentrations can improve performance via increased nutrient intake.

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