Influence of Turbidity on Foraging Behaviour in Three-Spined Sticklebacks (Gasterosteus aculeatus)

Anthropogenic activities increase turbidity in coastal marine environments globally, and turbidity is particularly caused by eutrophication. Turbidity is a measurement of the scattering and absorption of light by suspended matter in water. An increase in turbidity influences visual predators and affects community structures and whole ecosystems. The three-spined stickleback (Gasterosteus aculeatus) is a widespread species in the northern hemispheric Pacific and Atlantic oceans. It is a visual predator and, therefore, a very well-suited species for studying the effects of increasing turbidity on foraging behaviour and activity. Sticklebacks used for this study were from an aquarium in the North Sea Oceanarium. They have been in the aquarium for around two months and were originally collected in a highly eutrophicated marine fjord system. They were individually placed in an observation aquarium, fed with krill, given 10 min to forage, and observed by video cameras. The video films were analysed to study stickleback predation behaviour. Experiments were repeated with four different turbidity treatments, ranging from a mean of 0.034 up to 10 NTU (nephelometric turbidity unit). Bentonite clay was used as a turbidity-increasing substance. A statistically significant difference in foraging behaviour and activity between the turbidity treatments was observed. The test subjects were found to lunge less for prey and had a higher feeding latency with increasing turbidity. Additionally, they were less active with increasing turbidity. The behavioural instability estimated as a variation in feeding latency increased with increasing turbidity but decreased at the highest turbidity value. Our study indicates an effect of turbidity-increasing events on the behaviour of the three-spined stickleback and potentially also other similar visual predators

Is Virtual Fencing an Effective Way of Enclosing Cattle? Personality, Herd Behaviour and Welfare

In modern nature conservation and rewilding there is a need for controlling the movements of large grazers in extensively managed areas. The inflexibility of physical fencing can be a limitation in nature management, and the physical boundaries created by physical fencing can have detrimental effects on wildlife. Virtual fencing systems provide boundaries without physical structures. These systems utilise collars with GPS technology to track animals and deliver auditory or electric cues to encourage the animals to stay within the predefined boundaries. This study aims to assess the use of virtual fencing (Nofence©) to keep twelve Angus cows (Bos taurus) within a virtual enclosure without compromising their welfare. As such, the study examines inter-individual differences between the cows as well as their herd behaviour, when reacting and learning to respond appropriately to virtual fencing. Moreover, the activity of the cows was used as an indicator of welfare. The virtual fencing was successful in keeping the herd within the designated area. Moreover, the cattle learned to avoid the virtual border and respond to auditory cues, where the cows received significantly more auditory warning and electric impulses per week throughout the first 14 days than the remaining 125 days (p < 0.001). The cows were found to express both inter-individual differences (p < 0.001) and herd behaviour. The cattle did not express any significant changes in their activity upon receiving an electrical impulse from the collar. Thus, indicating that there were little to no acute welfare implications associated with the use of virtual fencing in this study. This study clearly supports the potential for virtual fencing as a viable alternative to physical electric fencing. However, it also shows that both individual differences in personality and herd structure should be considered when selecting individuals for virtual fencing

Rationale, design, and baseline characteristics in Evaluation of LIXisenatide in Acute Coronary Syndrome, a long-term cardiovascular end point trial of lixisenatide versus placebo

BACKGROUND: Cardiovascular (CV) disease is the leading cause of morbidity and mortality in patients with type 2 diabetes mellitus (T2DM). Furthermore, patients with T2DM and acute coronary syndrome (ACS) have a particularly high risk of CV events. The glucagon-like peptide 1 receptor agonist, lixisenatide, improves glycemia, but its effects on CV events have not been thoroughly evaluated. METHODS: ELIXA (www.clinicaltrials.gov no. NCT01147250) is a randomized, double-blind, placebo-controlled, parallel-group, multicenter study of lixisenatide in patients with T2DM and a recent ACS event. The primary aim is to evaluate the effects of lixisenatide on CV morbidity and mortality in a population at high CV risk. The primary efficacy end point is a composite of time to CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. Data are systematically collected for safety outcomes, including hypoglycemia, pancreatitis, and malignancy. RESULTS: Enrollment began in July 2010 and ended in August 2013; 6,068 patients from 49 countries were randomized. Of these, 69% are men and 75% are white; at baseline, the mean ± SD age was 60.3 ± 9.7 years, body mass index was 30.2 ± 5.7 kg/m(2), and duration of T2DM was 9.3 ± 8.2 years. The qualifying ACS was a myocardial infarction in 83% and unstable angina in 17%. The study will continue until the positive adjudication of the protocol-specified number of primary CV events. CONCLUSION: ELIXA will be the first trial to report the safety and efficacy of a glucagon-like peptide 1 receptor agonist in people with T2DM and high CV event risk