Towards understanding the impacts of the pet food industry on world fish and seafood supplies

The status of wild capture fisheries has induced many fisheries and conservation scientists to express concerns about the concept of using forage fish after reduction to fishmeal and fish oil, as feed for farmed animals, particularly in aquaculture. However, a very large quantity of forage fish is being also used untransformed (fresh or frozen) globally for other purposes, such as the pet food industry. So far, no attempts have been made to estimate this quantum, and have been omitted in previous fishmeal and fish oil exploitation surveys. On the basis of recently released data on the Australian importation of fresh or frozen fish for the canned cat food industry, here we show that the estimated amount of raw fishery products directly utilized by the cat food industry equates to 2.48 million metric tonnes per year. This estimate, plus the previously reported global fishmeal consumption for the production of dry pet food suggest that 13.5% of the total 39.0 million tonnes of wild caught forage fish is used for purposes other than human food production. This study attempts to bring forth information on the direct use of fresh or frozen forage fish in the pet food sector that appears to have received little attention to this date and that needs to be considered in the global debate on the ethical nature of current practices on the use of forage fish, a limited biological resource.

Audit of the Douglas Hocking Research Institute bone bank : ten years of non-irradiated bone graft

Background:  An audit performed in the use of non-irradiated femoral head bone graft at the Geelong Hospital over a 10-year period. While it is thought the non-irradiated bone graft provides a better structural construct there is theoretical increased risk of infection transmission.

Methods:  We performed a retrospective review of prospectively collected data in the use of non-irradiated bone allograft used from the Geelong Hospital Douglas Hosking Research Institute bone bank over a 10-year period. The review was performed using data collected from the bone bank and correlating it with the patient’s medical record. All complications, including infections, related to the use of the allograft were recorded.

Results:  We found that over the 10 years to 2004 that 811 femoral heads were donated, with 555 being used over 362 procedures in 316 patients. We identified a total of nine deep infections, of which seven were in joint replacements. Overall this was a 2.5% deep infection rate, which was lowered to 1.4% if the previously infected joints that were operated on were excluded.

Conclusion:  The use of non-irradiated femoral head bone graft was safe in a regional setting.

Turnover of bone marrow-derived cells in the irradiated mouse cornea

In light of an increasing awareness of the presence of bone marrow (BM)-derived macrophages in the normal cornea and their uncertain role in corneal diseases, it is important that the turnover rate of these resident immune cells be established. The baseline density and distribution of macrophages in the corneal stroma was investigated in Cx3cr1gfp transgenic mice in which all monocyte-derived cells express enhanced green fluorescent protein (eGFP). To quantify turnover, BM-derived cells from transgenic eGFP mice were transplanted into whole-body irradiated wild-type recipients. Additionally, wild-type BM-derived cells were injected into irradiated Cx3cr1+/gfp recipients, creating reverse chimeras. At 2, 4 and 8 weeks post-reconstitution, the number of eGFP+ cells in each corneal whole mount was calculated using epifluorescence microscopy, immunofluorescence staining and confocal microscopy. The total density of myeloid-derived cells in the normal Cx3cr1+/gfp cornea was 366 cells/mm2. In BM chimeras 2 weeks post-reconstitution, 24% of the myeloid-derived cells had been replenished and were predominantly located in the anterior stroma. By 8 weeks post-reconstitution 75% of the myeloid-derived cells had been replaced and these cells were distributed uniformly throughout the stroma. All donor eGFP+ cells expressed low to moderate levels of CD45 and CD11b, with approximately 25% coexpressing major histocompatibility complex class II, a phenotype characteristic of previous descriptions of corneal stromal macrophages. In conclusion, 75% of the myeloid-derived cells in the mouse corneal stroma are replenished after 8 weeks. These data provide a strong basis for functional investigations of the role of resident stromal macrophages versus non-haematopoietic cells using BM chimeric mice in models of corneal inflammation.

Gamma-irradiated carbon nanotube yarn as substrate for high-performance fiber supercapacitors

As an electrical double layer capacitor, dry-spun carbon nanotube yarn possesses relatively low specific capacitance. This can be significantly increased as a result of the pseudocapacitance of functional groups on the carbon nanotubes developed by oxidation using a gamma irradiation treatment in the presence of air. When coated with high-performance polyaniline nanowires, the gamma-irradiated carbon nanotube yarn acts as a high-strength reinforcement and a high-efficiency current collector in two-ply yarn supercapacitors for transporting charges generated along the long electrodes. The resulting supercapacitors demonstrate excellent electrochemical performance, cycle stability, and resistance to folding-unfolding that are required in wearable electronic textiles.

Incorporating carbon footprints into seafood sustainability certification and eco-labels

The seafood industry has become increasingly interconnected at a global scale, with fish the most traded commodity worldwide. Travel to the farthest reaches of the oceans for capture is now common practice, and subsequent transport to market can require hundreds to thousands of miles of travel by sea and air. Refrigeration of seafood products is generally required at all stages of the journey from ocean to dinner plate, resulting in substantial energy expenditure. Energy input for aquaculture (including mariculture) products can also be high, namely due to the large amounts of feed required to support fish growth. As a result of these factors, the seafood industry has a substantial carbon footprint. Surprisingly, however, carbon footprints of seafood products are rarely integrated into assessments of their sustainability by eco-labels, sustainability certification, or consumer seafood sustainability guides. Suggestions are provided here for how carbon footprints could be incorporated within seafood sustainability schemes.

Recreational drug use within the employees of the mariculture and seafood industry in South Australia

A study of recreational drug use among workers in the Port Lincoln mariculture and seafood industries was conducted by self report questionnaire. High rates of cannabis and alcohol use were revealed during the shore based fish farming season. The occupational health and safety implications of these findings in one of Australia's most dangerous industries are significant. Further research could inform the development of industry specific harm minimisation policies.