Evidence of sound production by spawning lake trout (Salvelinus namaycush) in lakes Huron and Champlain

Two sounds associated with spawning lake trout (Salvelinus namaycush) in lakes Huron and Champlain were characterized by comparing sound recordings with behavioral data collected using acoustic telemetry and video. These sounds were named “growls” and “snaps” and were heard on lake trout spawning reefs, but not on a nonspawning reef, and were more common at night than during the day. Growls also occurred more often during the spawning period than the prespawning period, while the trend for snaps was reversed. In a laboratory flume, sounds occurred when male lake trout were displaying spawning behaviors: growls when males were quivering and parallel swimming and snaps when males moved their jaw. Combining our results with the observation of possible sound production by spawning splake (Salvelinus fontinalis × Salvelinus namaycush hybrid) provides rare evidence for spawning-related sound production by a salmonid or any other fish in the superorder Protacanthopterygii. Further characterization of these sounds could be useful for lake trout assessment, restoration, and control

Mice expressing a human KATP channel mutation have altered channel ATP sensitivity but no cardiac abnormalities

AIMS/HYPOTHESIS: Patients with severe gain-of-function mutations in the Kir6.2 subunit of the ATP-sensitive potassium (K(ATP)) channel, have neonatal diabetes, muscle hypotonia and mental and motor developmental delay-a condition known as iDEND syndrome. However, despite the fact that Kir6.2 forms the pore of the cardiac K(ATP) channel, patients show no obvious cardiac symptoms. The aim of this project was to use a mouse model of iDEND syndrome to determine whether iDEND mutations affect cardiac function and cardiac K(ATP) channel ATP sensitivity. METHODS: We performed patch-clamp and in vivo cine-MRI studies on mice in which the most common iDEND mutation (Kir6.2-V59M) was targeted to cardiac muscle using Cre-lox technology (m-V59M mice). RESULTS: Patch-clamp studies of isolated cardiac myocytes revealed a markedly reduced K(ATP) channel sensitivity to MgATP inhibition in m-V59M mice (IC(50) 62 μmol/l compared with 13 μmol/l for littermate controls). In vivo cine-MRI revealed there were no gross morphological differences and no differences in heart rate, end diastolic volume, end systolic volume, stroke volume, ejection fraction, cardiac output or wall thickening between m-V59M and control hearts, either under resting conditions or under dobutamine stress. CONCLUSIONS/INTERPRETATION: The common iDEND mutation Kir6.2-V59M decreases ATP block of cardiac K(ATP) channels but was without obvious effect on heart function, suggesting that metabolic changes fail to open the mutated channel to an extent that affects function (at least in the absence of ischaemia). This may have implications for the choice of sulfonylurea used to treat neonatal diabetes

Data from: A carbohydrate-rich diet increases social immunity in ants

Increased potential for disease transmission among nest-mates means living in groups has inherent costs. This increased potential is predicted to select for disease resistance mechanisms that are enhanced by cooperative exchanges among group members, a phenomenon known as social immunity. One potential mediator of social immunity is diet nutritional balance because traits underlying immunity can require different nutritional mixtures. Here, we show how dietary protein–carbohydrate balance affects social immunity in ants. When challenged with a parasitic fungus Metarhizium anisopliae, workers reared on a high-carbohydrate diet survived approximately 2.8× longer in worker groups than in solitary conditions, whereas workers reared on an isocaloric, high-protein diet survived only approximately 1.3× longer in worker groups versus solitary conditions. Nutrition had little effect on social grooming, a potential mechanism for social immunity. However, experimentally blocking metapleural glands, which secrete antibiotics, completely eliminated effects of social grouping and nutrition on immunity, suggesting a causal role for secretion exchange. A carbohydrate-rich diet also reduced worker mortality rates when whole colonies were challenged with Metarhizium. These results provide a novel mechanism by which carbohydrate exploitation could contribute to the ecological dominance of ants and other social groups

Evidence of sound production by spawning lake trout (Salvelinus namaycush) in lakes Huron and Champlain

Two sounds associated with spawning lake trout (Salvelinus namaycush) in lakes Huron and Champlain were characterized by comparing sound recordings to behavioral data collected using acoustic telemetry and video. These sounds were named growls and snaps, and were heard on lake trout spawning reefs, but not on a non-spawning reef, and were more common at night than during the day. Growls also occurred more often during the spawning period than the pre-spawning period, while the trend for snaps was reversed. In a laboratory flume, sounds occurred when male lake trout were displaying spawning behaviors; growls when males were quivering and parallel swimming, and snaps when males moved their jaw. Combining our results with the observation of possible sound production by spawning splake (Salvelinus fontinalis Ă Salvelinus namaycush hybrid), provides rare evidence for spawning-related sound production by a salmonid, or any other fish in the superorder Protacanthopterygii. Further characterization of these sounds could be useful for lake trout assessment, restoration, and control.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Kay et al RSPB-2013-2374 allogrooming data

In June 2012, we assessed whether diet affects allogrooming, an established mechanism of social immunity in ants (Hughes et al. 2002). We assigned 24 colonies to either the 1P:3C or 3P:1C diet, as above. After an 18-day rearing period, we created solitary ant and worker group sets and treated them with either Metarhizium or the control Triton-X solution. We then immediately began assaying grooming behaviour after Walker & Hughes (2011). We observed behaviour for 30-s periods at every 10 min for 60 min, as most grooming occurs immediately after solution application (pers. obs., also Walker & Hughes, 2009). We recorded the number of antennal self-grooming and allo-grooming events. Behaviours that occurred for more than a 5-s period were split into multiple events

Kay et al RSPB-2013-2374 worker survivorship experiment, untreated ants

For survival assays, we measured responses of solitary and social ant groupings to treatment with M. anisopliae (strain KVL02-73 collected at this site (Hughes et al. 2004)). After the 18-day diet manipulation, we created 1-ant (solitary ants) or 5-ant (worker groups) sets from each colony. In Jan 2012, we assigned 5 solitary ants and 1 worker group per colony to a control treatment (not challenged with Metarhizium)

Kay et al RSPB-2013-2374 evidence of infection in metapleural blockage experiment

In survivorship experiments, we removed dead ants, sterilized them (with 1% NaClO), placed them on filter paper, and monitored them for 7 days for signs of Metarhizium infection (characteristic conidia growth that occurs within 2-3 days)

Kay et al RSPB-2013-2374 food intake in the colony level experiment

For this test, we used 16 colonies in June 2011 and 10 in January 2012. We assigned colonies (blocked by size as above) to the 1P:3C or 3P:1C diet, and removed larvae from half of the colonies in each treatment; we removed and returned larvae for control colonies. We reared colonies for 21 days. During the rearing period, we challenged colonies with Metarhizium by placing headless ant corpses covered in Metarhizium spores in each nest every 2 days