Egg production rates of Calanus finmarchicus in the Northwest Atlantic (Labrador Sea)

1997 ◽  
Vol 54 (6) ◽  
pp. 1270-1279 ◽  
Author(s):  
J Cabal ◽  
L R Harris ◽  
EJH Head
Keyword(s):  
Egg Production ◽  
Population Characteristics ◽  
Calanus Finmarchicus ◽  
Labrador Sea ◽  
Production Rates ◽  
In Situ Conditions ◽  
Different Types ◽  
Series Of Experiments

Egg production rates and population characteristics of Calanus finmarchicus were examined in the Labrador Sea during the spring of 1994. Several experiments were conducted in order to compare egg production rates and clutch size using different types of container and in the presence and absence of food. In one series of experiments, individual females were incubated either in petri dishes or in polycarbonate bottles (80 mL) in filtered seawater. In these experiments, clutch sizes and egg production rates were not significantly different. In a second series of experiments, groups of 20 females were placed in containers under three sets of conditions: in the presence of food and with a screen to separate copepods from their eggs (FSCREEN), in the presence of food without a screen (FOOD), and in filtered seawater without a screen (FSW). Average egg production rates of female C. finmarchicus were significantly higher in the FSCREEN treatments than in either of the other two. In these experiments, egg production rates were not obviously related to ingestion rates, and these in vitro observations together with observations of in situ conditions suggest that stored reserves may have been used to fuel, or supplement, reproduction in C. finmarchicus in this area.

Measurement of Egg Production Rate of Calanus finmarchicus from Preserved Samples

1987 ◽  
Vol 44 (11) ◽  
pp. 2009-2012 ◽  
Author(s):  
Jeffrey A. Runge
Keyword(s):  
Nova Scotia ◽  
Water Column ◽  
Production Rate ◽  
Egg Production ◽  
Gonadal Development ◽  
Calanus Finmarchicus ◽  
Production Rates ◽  
Daily Production ◽  
Egg Production Rate

A method for determining Calanus egg production rates from preserved, net-tow samples is proposed. In the sea off Nova Scotia, in situ egg production rates (eggs per female per day) of Calanus finmarchicus are significantly related to an index of gonadal development in preserved females. This relationship could be used in combination with data on female abundance to estimate daily production of eggs in the water column. The method is illustrated with data from a transect across Browns Bank.

scholarly journals B-1 cell: the precursor of a novel mononuclear phagocyte with immuno-regulatory properties

2009 ◽  
Vol 81 (3) ◽  
pp. 489-496 ◽  
Author(s):  
José Daniel Lopes ◽  
Mario Mariano
Keyword(s):  
Mammalian Cells ◽  
Giant Cells ◽  
Mononuclear Phagocyte ◽  
Different Types ◽  
Series Of Experiments ◽  
B1 Cells ◽  
Regulatory Properties

Characterization of the origin, properties, functions and fate of cells is a fundamental task for the understanding of physiological and pathological phenomena. Despite the bulk of knowledge concerning the diverse characteristics of mammalian cells, some of them, such as B-1 cells, are still poorly understood. Here we report the results obtained in our laboratory on these cells in the last 10 years. After showing that B-1 cells could be cultured and amplified in vitro, a series of experiments were performed with these cells. They showed that B1 cells reside mostly in the peritoneal and pleural cavities, migrate to distant inflammatory foci, coalesce to form giant cells and participate in granuloma formation, both in vitro and in vivo. They are also able to present antigens to immunologically responsive cells and are endowed with regulatory properties. Further, we have also shown that these cells facilitate different types of infection as well as tumor growth and spreading. These data are presently reviewed pointing to a pivotal role that these cells may play in innate and acquired immunity.

Aging of Cryptosporidium parvum oocysts in river water and their susceptibility to disinfection by chlorine and monochloramine

1998 ◽  
Vol 44 (12) ◽  
pp. 1154-1160 ◽  
Author(s):  
Christian Chauret ◽  
Kerry Nolan ◽  
Ping Chen ◽  
Susan Springthorpe ◽  
Syed Sattar
Keyword(s):  
Cryptosporidium Parvum ◽  
Environmental Fate ◽  
Water Environment ◽  
Water Disinfection ◽  
Ottawa River ◽  
In Situ Conditions ◽  
Cryptosporidium Parvum Oocysts ◽  
St Lawrence River

Cryptosporidium parvum oocysts were aged in waters from both the St. Lawrence River and the Ottawa River. In situ survival experiments were carried out by incubating the oocysts in either dialysis cassettes or microtubes floated into an overflow tank. A significant portion of the oocysts survived in the test waters for several weeks. Oocyst survival in the St. Lawrence River was better in membrane-filtered (0.2-µm-pore diameter) water than in unfiltered water, suggesting that biological antagonism may play a role in the environmental fate of the parasite. Oocysts aged in river waters under in situ conditions and control oocysts kept refrigerated in synthetic water (100 ppm as CaCO3; pH 7.0) were subjected to the same disinfection protocol. Aged oocysts were at least as resistant as, if not more resistant than, the control oocysts to disinfection. This indicates that the oocysts surviving in the water environment may be just as difficult to inactivate by potable water disinfection as freshly shed oocysts. Therefore, water treatment should not be based on the assumption that environmental oocysts may be more easily inactivated than freshly shed oocysts. First-order kinetics die-off rates varied from one river to another (from 0.013 to 0.039 log10·day-1) and from one experiment to another with water from the same river collected at different times. Calculation of the die-off rates based on either in vitro excystation or in vitro excystation in combination with total counts (overall die-off rates) showed that the assessment of oocyst viability by microscopic methods must account for the total oocyst loss observed during long-term inactivation assays of river waters.Key words: Cryptosporidium, survival, disinfection, biological antagonism.

scholarly journals Characteristics of egg production of the planktonic copepod, Calanus finmarchicus, in the Labrador Sea: 1997–2010

2012 ◽  
Vol 35 (2) ◽  
pp. 281-298 ◽  
Author(s):  
Erica J. H. Head ◽  
Leslie R. Harris ◽  
Marc Ringuette ◽  
Robert W. Campbell
Keyword(s):  
Egg Production ◽  
Calanus Finmarchicus ◽  
Labrador Sea ◽  
Planktonic Copepod

scholarly journals In vitro studies of lactoferrin and murine granulopoiesis

Blood ◽  
1981 ◽  
Vol 57 (3) ◽  
pp. 574-578 ◽  
Author(s):  
EF Winton ◽  
JM Jr Kinkade ◽  
WR Vogler ◽  
MB Parker ◽  
KC Barnes
Keyword(s):  
Marrow Cell ◽  
Femoral Shaft ◽  
Conditioned Media ◽  
Target Cells ◽  
Peritoneal Cells ◽  
Different Types ◽  
Series Of Experiments ◽  
Dna 2 ◽  
Cell Colony

Human lactoferrin (LF) has been reported to inhibit in vitro granulopoiesis by means of decreasing colony-stimulating activity production by monocytes. We performed a series of experiments to determine if the reported experimental results could be replicated using highly purified murine LF and murine target cells. Three different types of experiments were performed. (1) Medium was conditioned by lung, femoral shaft, and adherent peritoneal cells in the presence and absence of LF, and the granulopoietic stimulating activity in the conditioned media was assayed by means of a 7-day agar colony assay and a 3-day liquid slide chamber assay, which quantitates 3H-TdR incorporation into DNA. (2) In cultures stimulated by an underlayer of adherent peritoneal cells, marrow cell colony formation in agar was determined after 7 days of culture in the presence or absence of LF. (3) LF was added to 3-day liquid marrow cell cultures that had been stimulated by lung or femoral shaft conditioned media. In all experimental situations, highly purified, iron-saturated LF in concentrations up to 10(-7) M had no effect on in vitro granulopoiesis. These results do not support LF's reputed regulatory role in granulopoiesis.

scholarly journals Efecto de Caryodendron orinocense sobre la degradación de la materia seca

2017 ◽  
Vol 28 (3) ◽  
pp. 667
Author(s):  
Pablo Losada Aguilar ◽  
Aurora Cuesta Peralta ◽  
Juan De Jesús Vargas Martínez
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Animal Nutrition ◽  
Carbohydrate Concentration ◽  
Randomized Design ◽  
In Situ Conditions ◽  
Dry Matter Degradation ◽  
Animal Sciences

The objective of the present study was to evaluate the in vitro and in situ dry matter degradation by including cacay cake (Caryodendron orinocense) on a diet based on Brachiaria dictyoneura. The experiment was developed in an animal nutrition laboratory on the Animal Sciences Faculty at the Universidad de Ciencias Aplicadas y Ambientales, Bogotá, Colombia, in July 2015. Four treatments were evaluated: B. dictyoneura, cacay cake and two mixtures of B. dictyoneura: cacay cake (80:20 and 60:40). The chemical composition and the in vitro and in situ degradability of the dry matter and the crude protein, at 48 hours were determined. The variables were analyzed through a complete randomized design with four treatments. The inclusion of cacay cake decreased the cell wall-associated with carbohydrate concentration and increased the higher digestibility nutrients; the crude protein and dry matter, in situ and in vitro degradability increased 22, 6 and 38%, respectively. In conclusion, the inclusion of cacay cake on a diet of B. dictyoneura improves dry matter degradation in vitro and in situ conditions.

Fetal lipoproteins and placental release of esterified lipids

1996 ◽  
Vol 8 (3) ◽  
pp. 457 ◽  
Author(s):  
JP Stammers ◽  
TJ Stephenson ◽  
JA Colley ◽  
D Hull
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Late Gestation ◽  
Free Fatty Acid Concentration ◽  
Fatty Acid Profiles ◽  
Rabbit Plasma ◽  
Albumin Solution ◽  
Series Of Experiments

An in vitro incubation technique was used to examine the release of lipids from the rabbit placenta. Free fatty acid, but not phospholipid or triacylglycerol, was released into the incubation media. In a second series of experiments, the addition of lipids to the umbilical circulation was studied in situ in the placenta of anaesthetized rabbits at late gestation. Each placenta was perfused from the fetal side in turn with two different perfusate solutions, either 4% bovine albumin solution or rabbit plasma. The rabbit plasma contained the appropriate carriers (lipoproteins) for esterified lipids, whereas the 4% albumin solution did not. The effluent perfusates were remarkably similar in free fatty acid concentration and composition, which closely matched the maternal free fatty acid profiles. The concentrations and fatty acid composition of the perfusate triacylglycerol and phospholipid fractions were unchanged by passage through the placenta, whether perfused with 4% albumin or with rabbit plasma. With this system, no evidence could be found for the addition of esterified lipids to the umbilical circulation in the rabbit despite the provision of appropriate carriers on the fetal side of the placenta.

scholarly journals Efficient Protocol for In vitro Regeneration of Ocimum sanctum using Nodal Segments as Explants

2021 ◽  
Vol 64 (1) ◽  
pp. 13-17
Author(s):  
Hammad Afzal Kayani ◽  
Mariam Raziq ◽  
Syeda Kahkashan Kazmi ◽  
Sheeba Naz ◽  
Saifullah Khan
Keyword(s):  
In Vitro Regeneration ◽  
Farmyard Manure ◽  
Nodal Segments ◽  
Direct Regeneration ◽  
Ocimum Sanctum ◽  
Different Types ◽  
Series Of Experiments ◽  
Indole 3 Acetic Acid ◽  
Benzyl Amino Purine

Ocimum sanctum commonly called (holy basil) an herb containing medicinal, ornamental values, is often used in culinary applications. This research focuses on the improved and efficient protocol for the direct regeneration and acclimatisation of Ocimum sanctum using nodal segments. Organogenesis and multiplication from explants were observed to a maximum on Murashige and Skoog (MS) medium supplemented with 0.1 mg/L of 6-Benzyl amino purine (BAP) and 0.025 mg/L of Indole-3-acetic acid (IAA). Furthermore, same medium was found effective for the induction of roots, in the in-vitro grown plantlets. A series of experiments were conducted to optimise the acclimatisation of in-vitro grown rooted plantlets of Ocimum sanctum. For this study different types of potting mix in assorted ratios were used  to obtain best supporting media for the acclimatisation, A7 media containing soil : farmyard manure (75:25) and A1 media containing (100%) sand were found best supporting medium for the acclimatisation and hardening of Ocimum sanctum.    

Egg production rates of Calanus finmarchicus in the western North Atlantic: effect of gonad maturity, female size, chlorophyll concentration, and temperature

2000 ◽  
Vol 57 (3) ◽  
pp. 518-529 ◽  
Author(s):  
Robert W Campbell ◽  
Erica JH Head
Keyword(s):  
Egg Production ◽  
Chlorophyll Concentration ◽  
Calanus Finmarchicus ◽  
Female Gonad ◽  
Female Size ◽  
Production Rates ◽  
Gonad Maturity ◽  
Spatial And Temporal Scales ◽  
Female Body Size ◽  
Egg Production Rate

Egg production rates of Calanus finmarchicus were measured in the Labrador Sea (spring) and on the Scotian Shelf (spring, summer, and autumn), in conjunction with indices of gonad maturity and food availability, female body size, surface layer temperature, and surface nitrate concentrations. Egg production rates were often two to four times higher than any previously reported at similar temperatures. Estimates of egg production rates of populations were most closely related to the proportion of reproductively mature females (as measured by a gonad stage index) and female size. Specifically, the gonad stage index (proportion of females capable of spawning) was correlated with the proportion of females that spawned during 24-h incubations, and female size determined the clutch size (i.e., number of eggs produced). Although there were detectable effects of food and temperature on egg production rates, they were generally weaker than the effect of female gonad maturity. Thus, over the broad spatial and temporal scales of this study, the reproductive (i.e., life history) status of a population was more important in determining its egg production rate than direct external factors (i.e., temperature and food conditions).

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