Use of state‐space modelling to identify ecological covariates associated with trends in pinniped demography

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Development of a rapid method for the sequential extraction and subsequent quantification of fatty acids and sugars from avocado mesocarp tissue

Methods devised for oil extraction from avocado (Persea americana Mill.) mesocarp (e.g., Soxhlet) are usually lengthy and require operation at high temperature. Moreover, methods for extracting sugars from avocado tissue (e.g., 80% ethanol, v/v) do not allow for lipids to be easily measured from the same sample. This study describes a new simple method that enabled sequential extraction and subsequent quantification of both fatty acids and sugars from the same avocado mesocarp tissue sample. Freeze-dried mesocarp samples of avocado cv. Hass fruit of different ripening stages were extracted by homogenization with hexane and the oil extracts quantified for fatty acid composition by GC. The resulting filter residues were readily usable for sugar extraction with methanol (62.5%, v/v). For comparison, oil was also extracted using the standard Soxhlet technique and the resulting thimble residue extracted for sugars as before. An additional experiment was carried out whereby filter residues were also extracted using ethanol. Average oil yield using the Soxhlet technique was significantly (P < 0.05) higher than that obtained by homogenization with hexane, although the difference remained very slight, and fatty acid profiles of the oil extracts following both methods were very similar. Oil recovery improved with increasing ripeness of the fruit with minor differences observed in the fatty acid composition during postharvest ripening. After lipid removal, methanolic extraction was superior in recovering sucrose and perseitol as compared to 80% ethanol (v/v), whereas mannoheptulose recovery was not affected by solvent used. The method presented has the benefits of shorter extraction time, lower extraction temperature, and reduced amount of solvent and can be used for sequential extraction of fatty acids and sugars from the same sample.     

Anthropogenic radionuclides in tide-washed pastures bordering the Irish Sea coast of England and Wales

The activity concentrations of 137Cs,²³⁸ Pu, ^239,240Pu and ²⁴¹Am were measured in root mat and vegetation samples collected from tide washed pastures in 17 estuaries spanning the eastern seaboard of the Irish Sea, extending from the Solway in north-west England to St. David's Head in south Wales. Some of these estuaries had been investigated in previous surveys, but this study is unique in that it covered a wide geographic range using the same sampling and analytical methodology and within a comparatively short time scale. This allows for a valid comparison within the data set of the contamination levels at the different areas. Spatial distributions of the radionuclides were consistent with transport of radionuclides discharged to the Irish Sea from the Sellafield Nuclear Reprocessing Plant, with the highest activities occurring in the Esk estuary (closest to Sellafield) and lowest at the Welsh sites. Measurable activity concentrations of²³⁸ Pu and ^239,240Pu were found in root mat samples from the Solway estuary to as far south as the Gwyrfai in Wales and showed an average²³⁸ Pu/^239,240Pu ratio of 0.2, consistent with Sellafield-derived Pu. The ratios of¹³⁷ Cs/²⁴¹Am increased with distance from the source, with values of 1:1 in estuaries near Sellafield to ratios between 2 and 5 in estuaries further south and in excess of 10:1 in Wales. This is probably due to the more rapid movement of dissolved¹³⁷ Cs in Irish Sea waters compared with the actinides. In contrast, ²⁴¹Am and ^239,240Pu behave similarly with consistent ratios of between 2:1 and 3:1, as both are associated with particulates. Dose assessment calculations suggest that external exposure would be a maximum of 530 µSv at the most contaminated spot at the Esk estuary. Relatively lower doses arise from the ingestion of animal products (along the soil-vegetation-grazing animal pathway) due to the low availability of sediment-associated radionuclides for gut transfer. The dose assessment calculations highlight the importance of using the appropriate transfer parameters that take into account this low bioavailability.     

Laparoscopic Cystotomy for Removal of a Large Bladder Polyp in a Juvenile Alpaca with Polypoid Cystitis

Objective: To describe a method for laparoscopic cystotomy in an alpaca. Study Design: Case report. Animals: Female alpaca. Methods: An 8‐month‐old female alpaca was admitted with a 6‐week history of straining to urinate and vulvar swelling. Transrectal ultrasound examination revealed a 1.5 × 1.5 × 2 cm polyp within the bladder. Results: The mass was excised using laparoscopic cystotomy. Leakage from the cystotomy site resolved over 12 days using a Foley catheter. The alpaca was healthy and urinating normally at 9 months after surgery. Conclusion: Minimally invasive surgery by laparoscopic cystotomy can be used to remove large urinary polyps in alpacas. Clinical Relevance: Urinary bladder polyps should be considered as differential diagnosis in alpacas with stranguria.     

Comparison of the effects of an intravenous lidocaine infusion combined with 1% isoflurane versus 2% isoflurane alone on selected cardiovascular variables and recovery characteristics during equine general anaesthesia

Objectives

To compare the effects of a lidocaine constant rate infusion (CRI) combined with 1% isoflurane versus those of 2% isoflurane alone on cardiovascular variables in anaesthetized horses, and to estimate the sample size required to detect a difference in recovery quality.

Is bigger better? Apidae (Xylocopinae), megachilidae and cowpea (Vigna unguiculata) pollination

Cowpea is an important grain legume crop in Africa. Cowpea flowers are capable of self-fertilization, which might be the most frequent type of reproduction. Nevertheless, the rate of cross-pollination could vary between 1% and 10%, depending on the populations of bumblebees or domestic bees that are present, the climate and the cultivar. The aim of this study was to identify and assess the efficiency rate of the pollinators of the wild cowpea, Vigna unguiculata subsp. unguiculata var. spontanea, the progenitor of the domesticated cowpea Vigna unguiculata subsp. unguiculata. Pollination study was conducted by observing patches of flowers (average 10–20/m²) from dawn to midday, approximately 05:00–12:30 hr for three years. All insects visiting the flowers were noted and identified to species level, where possible, and their foraging behaviour was monitored. Pollen grain deposit and pod set were estimated using single bee visits on plants with strictly outcrossing flowers. Major flower visitors were large bees of the family Megachilidae and the genus Xylocopa (Apidae, Xylocopinae). Xylocopa caffra (Linnaeus) was the most abundant bee species, accounting for 59% of total bees observed and 58% of total flower visited. Pod set was higher in visits by megachilid bees compared to Xylocopa bees. Within Xylocopa, there is a good correlation between size and efficiency (r = .95, p = .0477), the larger insects being more efficient. Honeybees, small bees (Ceratina and Nomia species) and Lepidopterans also visited flowers but without any effect on pollination. Cowpea pollination system is specialized, and pollinators are restricted to Megachilidae and Xylocopa species. Variation in pollen load deposit and pod set reveals that pollination success depends on the insect species involved and their size. Megachilids are the most efficient pollinators, especially since they are able to promote outcrossing more efficiently than Xylocopa species.     

Comparison of polyglactin-910 and polydioxanone for closure of the linea alba following caudal ventral midline laparotomy in sheep

This study compared incisional complications after ventral midline laparotomy using 2 absorbable suture materials for apposition of the linea alba in sheep. The linea alba of 93 yearling sheep was sutured by 3 veterinarians in a simple continuous pattern using either polyglactin 910 (PG910; group PG) or polydioxanone (PDS; group PD). A blinded observer assessed surgical sites at the time of suture removal. Multivariate logistic regression was used to assess the association between incisional complications and variables (suture material used, veterinarian, skin suture removal time). The odds of incisional complications did not vary significantly with the type of suture material used (P = 0.11), veterinarian (P = 0.61) or skin suture removal time (P = 0.36). Most incisional complications were cutaneous suture sinus formation. Either PG910 or PDS may be used for linea alba closure in sheep.     

Severe lymphocytic-plasmacytic and atrophic gastritis, as well as, predominantly eosinophilic, severe enteritis, in a 19-month-old Labrador retriever

A 19-month-old, male, Labrador retriever was presented with a history of chronic vomiting. Blood analysis and abdominal ultrasononography could not rule out the possibility of gastrointestinal inflammation. Histologic examination of endoscopic gastrointestinal biopsies confirmed severe lymphocytic-plasmacytic and atrophic gastritis, as well as, predominantly eosinophilic, severe enteritis.