Biochemical markers of bone metabolism in growing thoroughbreds: a longitudinal study

This study describes longitudinal changes in serum levels of biochemical markers of bone cell activity in a group of 24 thoroughbred foals from birth to 18 months of age. The markers of bone formation included the type I collagen carboxy-terminal propeptide (PICP), the bone-specific isoenzyme of alkaline phosphatase (BAP), and osteocalcin (OC). Levels of the cross-linked telopeptide of type I collagen (ICTP), a marker of bone resorption, and the N-terminal propeptide of type III collagen (PNIIIP), a marker of soft tissue turnover, were also measured. Levels of all markers fell significantly between birth and 18 months of age (70-80 per cent); this decrease being most marked between 0 and 6 months. However, a transient increase in levels of the markers then occurred between 6 and 14 months of age. The timing of this increase was specific for each parameter. ICTP and OC concentrations increased between October and December. PICP concentrations increased between December and April whereas the increase in PIIINP was coincident with the peak in weight gain between April and June. Changes in BAP concentration were less distinct at this time. Season was shown to have significant effects on the biochemical markers independent from the effect of age. Concentrations of all markers decreased with increasing body weight and at any given age heavier horses had lower marker levels. These results show that biochemical markers of bone cell activity and soft tissue turnover follow characteristic patterns of change in growing thoroughbreds influenced by age, season and bodyweight. The demonstration that the reference ranges for the biochemical markers change from month to month means that single samples from individuals are of little value for monitoring bone cell activity in growing thoroughbreds.     

Distribution of Salmonella serovars and phage types on 80 Ontario swine farms in 2004

The objective of this study was to describe the distribution of Salmonella spp. on Ontario grower-finisher pig farms. Eighty swine farms were visited from January through July 2004. On each farm, fecal samples were collected from 5 pens, 2 rectal samples and 1 pooled sample from fresh manure on the floor per pen. Salmonella was isolated from 91 (11%) of the 800 rectal samples and 73 (18%) of the 397 pooled samples. Overall, Salmonella was recovered from 37 (46%) of the 80 farms. On each positive farm, Salmonella was cultured from 1 to 7 pigs or 1 to 5 pens. Of the 37 farms, 18, 13, 5, and 1 yielded 1, 2, 3, and 4 serovars, respectively. The most common serovars were S. Typhimurium var. Copenhagen, S. Infantis, S. Typhimurium, S. Derby, S. Agona, S. Havana, and S. enterica subsp. I:Rough-O. The 3 most frequent phage types were PT 104, PT 104a, and PT 104b. There was a statistically fair agreement between samples collected directly from pigs and pooled pen samples in determining the Salmonella status at the pen and farm level (kappa = 0.6, P < 0.0001). However, in 62 pens, Salmonella status, serovars, or phage types differed between the pig and pooled pen samples. The distribution of Salmonella on the swine farms in this study indicates that, in developing an intervention strategy, priority should be given to farms positive for S. Typhimurium var. Copenhagen. Also, the variation in Salmonella status between pig and pooled pen samples deserves consideration in a sampling strategy.     

Polypeptide composition of fraction 1 protein from parasexual hybrid plants in the genus Nicotiana

Analysis of the subunit polypeptide composition of Fraction 1 proteins gives information on the expression of both nuclear and chloroplast genomes; the large subunits of the protein are coded by chloroplast DNA, whereas the small subunits are coded by nuclear DNA. Fraction 1 protein isolated from the leaves of parasexual hybrid plants derived from the fusion of protoplasts of Nicotiana glauca and N. langsdorffii contains the small subunit polypeptides of both parent species and the large subunit polypeptides of only N. glauca. Fraction 1 protein isolated from the leaves of a hybrid plant obtained after the uptake of chloroplasts of N. suaveolens by protoplasts of white tissue of a variegating mutant of N. tabacum contains the large subunit polypeptides of both N. suaveolens and N. tabacum, as well as the small subunit polypeptides of both these species.     

Predicting the age of fish using general and generalized linear models of biometric data: A case study of two estuarine finfish from New South Wales, Australia

Direct ageing of fish can be a laborious and expensive task when age estimates from a large population are required, and often involves a degree of subjectivity. This study examined the application of general and generalized linear models that predict the age of fish from a range of efficiently and objectively measured covariates. The data sampled were from yellowfin bream (Acanthopagrus australis (Sparidae) (Owen, 1853)) and sand whiting (Sillago ciliata (Sillaginidae) Cuvier, 1829) populations from New South Wales, Australia. The covariates evaluated in the models were fish length, otolith weight, sex and location (the estuary from which the fish were sampled). Akaike Information Criteria were used for model selection and residual plots of the final models revealed a satisfactory fit to the observations. The best fitting model for each species included all covariates. An additional investigation considered whether general and generalized linear models that predict age from two different categories of biometric information outperform age-length keys with respect to subsequent estimates of total mortality from catch-curve analysis. The two categories of biometric information differed in the ease and cost with which the information could be collected. The first category only included fish length and location as covariates, whilst the second category also included otolith weight and sex. It was found that traditional age-length keys outperformed the predictive models that estimated age from only fish length and location, because the results from the models were prone to significant bias. However, when otolith weight and sex were added as covariates to the predictive models, some of them, including a generalized linear model with a Poisson-distributed response variable, performed similarly to the age-length key. Given that otolith weight and the sex of fish are cheaper to quantify than age from a sectioned otolith in many situations, general or generalized linear models may represent a cheaper and faster method of estimating mortality compared to age-length keys. Such models can also easily incorporate the influence of spatial, temporal and demographic variation.     

Cover Image,Volume 15, Issue 3

The cover image, by M. E. Gray et al., is based on the Original Article Dual targeting of EGFR and ERBB2 pathways produces a synergistic effect on cancer cell proliferation and migration in vitro, DOI: 10.1111/vco.12230 .

     

Turning back the tide of American mink invasion at an unprecedented scale through community participation and adaptive management

Successful eradications of harmful invasive species have been mostly confined to islands while control programs in mainland areas remain small, uncoordinated and vulnerable to recolonisation. To allow the recovery of threatened native species, innovative management strategies are required to remove invasives from large areas. We took an adaptive approach to achieve large scale eradication of invasive American mink in North East Scotland. The project was centred on the Cairngorms National Park (Scotland), with the primary aim of protecting endangered water vole populations. The project was initiated by scientists and supported and implemented through a partnership comprising a government agency, national park authority and local fisheries boards. Capitalising on the convergent interests of a diverse range of local stakeholders, we created a coordinated coalition of trained volunteers to detect and trap mink. Starting in montane headwaters, we systematically moved down river catchments, deploying mink rafts, an effective detection and trapping platform. Volunteers took increasing responsibility for raft monitoring and mink trapping as the project progressed. Within 3 years, the project removed 376 mink from 10570 km² with the involvement of 186 volunteers. Capture rate within sub-catchments increased with greater connectivity to mink in other sub-catchments and with proximity to the coast where there is more productive habitat. The main factor underpinning the success of this project was functional volunteer participation. The project is a reason for optimism that the tide of invasion can be rolled back on a large scale where the convergent interest of local communities can be harnessed.     

Poloxalene as an Anti-Bloat Compound and Its Effect on Milk Yield and Composition

Poloxalene, a nonionic surfactant, was fed to beef cattle on a legume ration or a high grain ration to observe its effect on bloat. It was also fed to lactating dairy cows to note any effect on yield or composition of milk.

Poloxalene was beneficial in the prevention of bloat with both legume and grain rations. It had no effect on per cent fat, protein, solids-not-fat, or yield of milk.