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• Anagonia spp. were found parasitizing 7% of field collected Gonipterus spp. larvae, in Tasmania. • One species, identified as Anagonia lasiophthalma , was successfully reared on Gonipterus platensis. • Females mated shortly after emergence and started parasitizing a week later. • On average, females produced 35 offspring and lived up to 84 days. • Biological traits suggest A. lasiophthalma may be effective against G. platensis. The Eucalyptus snout beetle, Gonipterus platensis , is one of the main pests of eucalypts outside its native range. Among the available control methods for this pest, classical biological control with Anaphes nitens (Hymenoptera: Mymaridae) has been the most widely used, but it is not always effective. To identify other natural enemies that might provide further pest control, a field survey was conducted in Tasmania, Australia, in which Anagonia spp. were found to parasitize 7 % of Gonipterus spp. larvae. One species was subsequently identified as the solitary parasitoid Anagonia lasiophthalma , based on direct comparisons with research collection material in Australia. To assess the potential of this species as a biological control agent, A. lasiophthalma was reared on G. platensis larvae under quarantine conditions, and its biology and reproductive strategy were studied in the laboratory. Global mating success was 58 %, with 66 of the 114 A. lasiophthalma females analyzed mating within an established 10-day period. Most females mated within 48 h after emergence and started to parasitize about a week later. Dissections of mated females showed that this species is ovolarviparous, incubating its eggs in an ovisac, before inserting them "ready-to-hatch" directly into the host using a piercing structure derived from the modification of a sternite in the female terminalia. Over the course of their lifetime, females on average produced 35 offspring and post-mortem dissections revealed an additional 32 eggs in the ovisac. Longevity of females and males was similar, ranging between 55 and 84 days, but females maintained without host larvae lived longer than females exposed to host larvae. These results provide relevant information to improve laboratory rearing protocols and suggest that A. lasiophthalma may be effective against the snout beetle in its invaded range. [ABSTRACT FROM AUTHOR]

This study investigated the effect of level of Spirulina supplementation on the fatty acid (FA ) compositions of subcutaneous adipose, longissimus dorsi muscle, kidney, heart, and liver tissues in purebred and crossbred Australian Merino sheep. Forty-eight lambs sired by Black Suffolk, White Suffolk, Dorset and Merino rams were assigned into 4 treatment groups of daily Spirulina supplementation levels per lamb of 0 mL (control), 50 mL (low), 100 mL (medium) and 200 mL (high) referred to as 0, 5, 10 and 20% groups. The lambs were slaughtered after 9 weeks of supplementation and heart, kidney, adipose, liver and muscle tissue samples were collected. The results demonstrated significant variations in growth and body conformation traits and tissue and organ FA composition in response to the Spirulina supplementation. The medium-level Spirulina treatment group increased the ω-3 and ω-6 polyunsaturated fatty acid (PUFA ) composition in all tissues and organs significantly. The results suggest the use of medium level (100 mL/head/day) of Spirulina supplementation in order to increase lamb production with more ω-3 and ω-6 PUFA and therefore higher nutritional meat quality. [ABSTRACT FROM AUTHOR]

Abstract: This study tested the effects of Spirulina supplementation level, basal diet and their interactions with sire breed and sex on liveweight, body conformation and growth traits in dual-purpose Australian lambs. In two concurrent feeding trials utilising typical pasture-based and simulated-drought basal diets, a total of 48 lambs was randomly allocated to treatment groups of Spirulina supplementation levels (CONTROL – 0ml, LOW – 50ml, MEDIUM – 100ml and HIGH – 200ml), balanced by sire breed (Black Suffolk, Dorset, Merino and White Suffolk) and sex (ewes and wethers). In both feeding trials, Spirulina was supplemented daily for 9-weeks, following a 3-week adjustment phase. Weekly data of liveweight and body conformation measurements; chest girth (CG), wither height, body length, and body condition score (BCS), were taken throughout the trials. These were transformed into changes between initial and final periods of the feeding trial. Average daily liveweight gain (ADG) was computed from the differences in liveweight divided by duration in days. All data were analysed using Factorial ANOVA analysis in SAS. Medium and high Spirulina supplementation levels were found to improve the liveweight and ADG of White Suffolk- and Merino-sired lambs on simulated-drought basal diets. BCS improved with Spirulina supplementation in lambs on simulated-drought basal diets. Under typical pasture-based basal diet, supplemented lambs had comparatively higher CG, BCS, liveweight and ADG than their counterparts on simulated-drought basal diets. These findings are of practical significance to the sheep industry because of the potential selection aid to Australian farmers in identifying the usefulness of Spirulina as a supplement and the optimal sire breed choice for the best performance response that is cost-effective when using dietary protein-rich supplements for their dual-purpose prime lamb operations. [Copyright &y& Elsevier]