Python farming as a flexible and efficient form of agricultural food security

Diminishing natural resources and increasing climatic volatility are impacting agri-food systems, prompting the need for sustainable and resilient alternatives. Python farming is well established in Asia but has received little attention from mainstream agricultural scientists. We measured growth rates in two species of large pythons (Malayopython reticulatus and Python bivittatus) in farms in Thailand and Vietnam and conducted feeding experiments to examine production efficiencies. Pythons grew rapidly over a 12-month period, and females grew faster than males. Food intake and growth rates early in life were strong predictors of total lifetime growth, with daily mass increments ranging from 0.24 to 19.7 g/day for M. reticulatus and 0.24 to 42.6 g/day for P. bivittatus, depending on food intake. Pythons that fasted for up to 4.2 months lost an average of 0.004% of their body mass per day, and resumed rapid growth as soon as feeding recommenced. Mean food conversion rate for dressed carcasses was 4.1%, with useable products (dressed carcass, skin, fat, gall bladder) comprising 82% of the mass of live animals. In terms of food and protein conversion ratios, pythons outperform all mainstream agricultural species studied to date. The ability of fasting pythons to regulate metabolic processes and maintain body condition enhances food security in volatile environments, suggesting that python farming may offer a flexible and efficient response to global food insecurity.

Oesophageal sarcocystosis observed at slaughter provides a reliable and efficient proximate measure of Toxoplasma gondii seroprevalence in sheep

OBJECTIVE

Successful disease management requires effective surveillance. Slaughterhouse inspections provide opportunities to efficiently collect regular disease data from many animals across large areas. Toxoplasma is a cat-borne parasite that causes reproduction failure in sheep, although it is not visually detectable at slaughterhouses. Macroscopic sarcocystosis is a disease of sheep that is visually detectable at slaughter and is caused by parasites that share a similar biology with Toxoplasma. We investigated if sarcocystosis could act as a proximate measure for Toxoplasma exposure in sheep to facilitate its efficient surveillance at large scales.

DESIGN/METHODS

We compared the presence of macroscopic sarcocystosis to Toxoplasma serostatus at the animal and farm levels.

RESULTS

At the animal level, we found a weak association between Toxoplasma seropositivity and sarcocysts in the oesophagus (OR = 1.76 [95% CI: 1.17, 2.65; _McFadden's R² = 0.01]) but no association between Toxoplasma seropositivity and sarcocysts in skeletal muscles. At the farm level, the seroprevalence of Toxoplasma was strongly associated with oesophageal sarcocystosis prevalence (OR = 28.59 [95% CI: 13.07, 62.57; _McFadden's R² = 0.34]) but less strongly associated with sarcocystosis prevalence in skeletal muscles (OR = 7.91 [95% CI: 1.24, 50.39; _McFadden's R² = 0.02]).

CONCLUSIONS

For Toxoplasma surveillance in sheep at the farm level, routine slaughter inspection and recording of macroscopic oesophageal sarcocystosis could be are liable and efficient proximate measure. The monitoring of oesophageal sarcocystosis may be a useful passive Toxoplasma surveillance tool for guiding the timing and location of other Toxoplasma detection methods to facilitate the management of Toxoplasma impacts within the sheep industry.

No Evidence of Toxoplasma Gondii Exposure in South Australian Koalas (Phascolarctos cinereus)

Infection with the cat-borne parasite Toxoplasma gondii has been detected in numerous Australian marsupials and can lead to severe disease (toxoplasmosis) in some cases. The seroprevalence of Toxoplasma on Kangaroo Island, South Australia has been reported to be higher than the South Australian mainland in macropods, cats, and sheep, suggesting an increased risk of infection on this island. However, Toxoplasma seroprevalence in small- and medium-sized terrestrial mammals was almost zero on the island and did not differ from that on the mainland. We surveyed Toxoplasma seroprevalence in koala (Phascolarctos cinereus) populations on the island and on the mainland and assessed their risk of infection and their role in the life cycle of Toxoplasma. All screened koalas from the island (n = 94) and the mainland (n = 63) were seronegative. This represents the largest Toxoplasma seroprevalence survey in this species and provided sufficient evidence to confidently demonstrate freedom from parasite exposure in both island and mainland populations at the time of the survey. Because koalas are extensively arboreal and predominately consume tree foliage, they appear to be at negligible risk of Toxoplasma infection. Furthermore, as koalas are rarely consumed by cats, we suggest that they have a minor role in the parasite's life cycle.