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Consequences of lower food intake on the digestive enzymes activities, the energy reserves and the reproductive outcome in Gammarus fossarum.

Charron L, Geffard O, Chaumot A, Coulaud R, Jaffal A, Gaillet V, Dedourge-Geffard O, Geffard A - PLoS ONE (2015)

Bottom Line: Energy reserves decreased with food starvation in females, and remained stable in males.The number of embryos per female decreased with food starvation.These results underline the ecological relevance of digestive markers, as they make it possible to anticipate upcoming consequences on reproduction in females, a key biological variable for population dynamics.

View Article: PubMed Central - PubMed

Affiliation: Université Reims Champagne Ardenne, Unité Mixte de Recherche-Ineris (UMR-I02) Stress Environnementaux et Biosurveillance des milieux aquatiques, Unité de Formation et de Recherche Sciences Exactes et Naturelles, Moulin de la Housse, Reims Cedex 2, France.

ABSTRACT
Digestive enzyme activity is often used as a sensitive response to environmental pollution. However, only little is known about the negative effects of stress on digestive capacities and their consequences on energy reserves and reproduction, although these parameters are important for the maintenance of populations. To highlight if changes in biochemical responses (digestive enzymes and reserves) led to impairments at an individual level (fertility), Gammarus fossarum were submitted to a lower food intake throughout a complete female reproductive cycle (i.e. from ovogenesis to offspring production). For both males and females, amylase activity was inhibited by the diet stress, whereas trypsin activity was not influenced. These results underline similar sensitivity of males and females concerning their digestive capacity. Energy reserves decreased with food starvation in females, and remained stable in males. The number of embryos per female decreased with food starvation. Lower digestive activity in males and females therefore appears as an early response. These results underline the ecological relevance of digestive markers, as they make it possible to anticipate upcoming consequences on reproduction in females, a key biological variable for population dynamics.

No MeSH data available.


Related in: MedlinePlus

Amylase (A, μg maltose/mg BSA/min) and trypsin (B, μg p-Na/mg BSA/min) activity levels in Gammarus fossarum exposed to 3 levels of food starvation (control: fed 7 days a week; 2/7: fed 2 days a week; 1/7: fed 1 day a week) after 11 and 43 days (means ± SD, n = 6).For each date and gender, bars with the same letter were not significantly different (p < 0.05). The hash (#) symbol points to significant changes between the two sampling times for each diet condition (p < 0.05).
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pone.0125154.g002: Amylase (A, μg maltose/mg BSA/min) and trypsin (B, μg p-Na/mg BSA/min) activity levels in Gammarus fossarum exposed to 3 levels of food starvation (control: fed 7 days a week; 2/7: fed 2 days a week; 1/7: fed 1 day a week) after 11 and 43 days (means ± SD, n = 6).For each date and gender, bars with the same letter were not significantly different (p < 0.05). The hash (#) symbol points to significant changes between the two sampling times for each diet condition (p < 0.05).

Mentions: For the both cycles, food starvation inhibited significantly amylase activity in males (p = 0.0394 for day 11; p = 0.0084 for day 43) and females (p = 0.0044 for day 11; p = 0.0124 for day 43) (Fig 2A). In females, significant differences between the most severely starved organisms (fed 1/7) and the controls (fed 7/7) were observed. Amylase activity was reduced by 31% and 36%, compared to the controls after 11 (p = 0.0039) and 43 days (p = 0.039) of starvation, respectively (Fig 2A). Between the two sampling times, amylase activity significantly decreased by 24 (p = 0.025), 23 (p = 0.037) and 29% (p = 0.004) for each of the 7/7, 2/7 and 1/7 feeding conditions in females. In males, amylase activity in the two starved conditions (1/7 and 2/7) was significantly lower than in the controls (1/7: p = 0.024 for day 11 and p = 0.0034 for day 43; and 2/7: p = 0.037 for day 11 and p = 0.024 for day 43) (Fig 2A). The highest starvation level (1/7) reduced amylase activity by 25 and 36% after 11 and 43 days, respectively, compared to the control, but no difference was noticed according to the length of food starvation (11 and 43 days) in males.


Consequences of lower food intake on the digestive enzymes activities, the energy reserves and the reproductive outcome in Gammarus fossarum.

Charron L, Geffard O, Chaumot A, Coulaud R, Jaffal A, Gaillet V, Dedourge-Geffard O, Geffard A - PLoS ONE (2015)

Amylase (A, μg maltose/mg BSA/min) and trypsin (B, μg p-Na/mg BSA/min) activity levels in Gammarus fossarum exposed to 3 levels of food starvation (control: fed 7 days a week; 2/7: fed 2 days a week; 1/7: fed 1 day a week) after 11 and 43 days (means ± SD, n = 6).For each date and gender, bars with the same letter were not significantly different (p < 0.05). The hash (#) symbol points to significant changes between the two sampling times for each diet condition (p < 0.05).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4400123&req=5

pone.0125154.g002: Amylase (A, μg maltose/mg BSA/min) and trypsin (B, μg p-Na/mg BSA/min) activity levels in Gammarus fossarum exposed to 3 levels of food starvation (control: fed 7 days a week; 2/7: fed 2 days a week; 1/7: fed 1 day a week) after 11 and 43 days (means ± SD, n = 6).For each date and gender, bars with the same letter were not significantly different (p < 0.05). The hash (#) symbol points to significant changes between the two sampling times for each diet condition (p < 0.05).
Mentions: For the both cycles, food starvation inhibited significantly amylase activity in males (p = 0.0394 for day 11; p = 0.0084 for day 43) and females (p = 0.0044 for day 11; p = 0.0124 for day 43) (Fig 2A). In females, significant differences between the most severely starved organisms (fed 1/7) and the controls (fed 7/7) were observed. Amylase activity was reduced by 31% and 36%, compared to the controls after 11 (p = 0.0039) and 43 days (p = 0.039) of starvation, respectively (Fig 2A). Between the two sampling times, amylase activity significantly decreased by 24 (p = 0.025), 23 (p = 0.037) and 29% (p = 0.004) for each of the 7/7, 2/7 and 1/7 feeding conditions in females. In males, amylase activity in the two starved conditions (1/7 and 2/7) was significantly lower than in the controls (1/7: p = 0.024 for day 11 and p = 0.0034 for day 43; and 2/7: p = 0.037 for day 11 and p = 0.024 for day 43) (Fig 2A). The highest starvation level (1/7) reduced amylase activity by 25 and 36% after 11 and 43 days, respectively, compared to the control, but no difference was noticed according to the length of food starvation (11 and 43 days) in males.

Bottom Line: Energy reserves decreased with food starvation in females, and remained stable in males.The number of embryos per female decreased with food starvation.These results underline the ecological relevance of digestive markers, as they make it possible to anticipate upcoming consequences on reproduction in females, a key biological variable for population dynamics.

View Article: PubMed Central - PubMed

Affiliation: Université Reims Champagne Ardenne, Unité Mixte de Recherche-Ineris (UMR-I02) Stress Environnementaux et Biosurveillance des milieux aquatiques, Unité de Formation et de Recherche Sciences Exactes et Naturelles, Moulin de la Housse, Reims Cedex 2, France.

ABSTRACT
Digestive enzyme activity is often used as a sensitive response to environmental pollution. However, only little is known about the negative effects of stress on digestive capacities and their consequences on energy reserves and reproduction, although these parameters are important for the maintenance of populations. To highlight if changes in biochemical responses (digestive enzymes and reserves) led to impairments at an individual level (fertility), Gammarus fossarum were submitted to a lower food intake throughout a complete female reproductive cycle (i.e. from ovogenesis to offspring production). For both males and females, amylase activity was inhibited by the diet stress, whereas trypsin activity was not influenced. These results underline similar sensitivity of males and females concerning their digestive capacity. Energy reserves decreased with food starvation in females, and remained stable in males. The number of embryos per female decreased with food starvation. Lower digestive activity in males and females therefore appears as an early response. These results underline the ecological relevance of digestive markers, as they make it possible to anticipate upcoming consequences on reproduction in females, a key biological variable for population dynamics.

No MeSH data available.


Related in: MedlinePlus