Over the last decade there has been a significant focus on the environmental impact of products and services across the economy, resulting in environmental product declarations and delivery agreements where the supplier is required to demonstrate an on-going improvement program of environmental sustainability. Once action is required, primary producers need to be able to make an objective assessment of their overall environmental impact using Life Cycle Assessment (LCA), so that "hot spots" in their production system can be identified, and options to reduce these impacts can be investigated. Country-specific Life Cycle Inventory (LCI) for agricultural products is essential for Australian agriculture to undertake environmental impact studies related to food and fibre, especially where differences in management systems and regional climate, soils and vegetation significantly affect LCA results. The goal of inventory collection for AusAgLCI is to provide underlying data to ensure Australian primary producers can readily, and objectively, demonstrate that their products are being produced in a responsible manner, in a system where environmental assessment is used to aid and drive improvements. This will assist producers to meet marketing requirements and to benchmark their production in global markets. This paper explores the relevance for horticulture industries and presents some inventory results for Australian horticultural products.

The animal food chain contributes significantly to emission of greenhouse gases (GHGs). We explored studies that addressed options to mitigate GHG emissions in the animal production chain and concluded that most studies focused on production systems in developed countries and on a single GHG. They did not account for the complex interrelated effects on other GHGs or their relation with other aspects of sustainability, such as eutrophication, animal welfare, land use or food security. Current decisions on GHG mitigation in animal production, therefore, are hindered by the complexity and uncertainty of the combined effect of GHG mitigation options on climate change and their relation with other aspects of sustainability. There is an urgent need to integrate simulation models at animal, crop and farm level with a consequential life cycle sustainability assessment to gain insight into the multidimensional and sometimes conflicting consequences of GHG mitigation options.

Two experiments yielded practical recommendations on design of cage equipment (mats and nest boxes) that can potentially improve the welfare and productivity of breeding does. The results show that, in the environment experienced by the experimental rabbits, sore hocks (pododermatitis) can be reduced in breeding does from an incidence of 4% down to less than 1%, by the provision of suitable pressure mats. The difference between the highest and lowest performing nest boxes, in terms of number of kittens weaned, translates into a difference in enterprise gross margins of A$52.35 per doe per annum, or an increase of 36% in profit from the use of the best performing nest box compared with the worst. Farmers can use the results as a guide to choosing or constructing nest box equipment, and should be encouraged to objectively compare different designs under their own environmental conditions.

Responding to concerns about the unsustainable use of global freshwater resources, especially in agriculture, the concept of water footprinting has recently been developed and applied to a wide range of commodities. In this paper, water footprints were calculated for two complex agrifood products, 250g Peanut M&M's® and 575g Dolmio® pasta sauce, in order to evaluate the usefulness of the concept when applied at the product brand level. The process LCA-based methodology took account of blue water appropriated from surface and groundwater resources, green water appropriated from the root zone by plants, and dilution water, being the volume of freshwater needed to assimilate emissions to freshwater. These case studies revealed several issues, namely the lack of correspondence between water footprints and the availability of water for alternative uses in the absence of production, and the difficulty in relating water footprints to potential social and environmental harm. As such, the water footprinting concept requires further development to be useful for promoting sustainable production and consumption.

A Bayesian analysis was performed in order to estim ate the genetic parameters of a binary trait based on the observed signs of enteropathy, 63-day body w eight, carcass yield and perirenal fat percentage in a commercial paternal line. There were 53,222 ra bbits inspected for signs of disease and 2,646 slaughtered rabbits for carcass traits from 1999 to July 2007. The incidence of digestive disorder was 8% of the population and 66% of these rabbits died prior to 63-day weighing. Estimated heritabilities were equal to 0.08, 0.36, 0.24 and 0.64 for the dis ase trait, 63-day body weight, carcass yield and perirenal fat percentage, respectively. The genetic correlations between the disease trait, on one han d, and the 63-d body weight and the carcass yield, on the other hand, were negative (-0.19 and -0.34, respectively) and so favorable. The genetic correla tion between the disease score and the perirenal fa t percentage was close to zero (-0.07). Therefore, it would be possible to reduce the incidence of enteropathy by including this binary trait in a bre eding program, if its relative economic value is hi gh enough to warrant its inclusion.

Incidence of visual signs of bacterial infection and mortality, from causes related to bacterial infection, were recorded on a weekly basis in growing meat rabbits from 5 to 10 weeks of age. Heritability of Weekly Incidence of disease was highest in weeks 9 and 10 (0.05 +/- 0.02 and 0.06 +/- 0.02, respectively with linear model, and 0.10 +/- 0.06 and 0.12 +/- 0.05, respectively with a threshold model). Common litter effects accounted for 5-20% of the variance of disease incidence, while maternal genetic variance was small (0-3 /0). Individuals from small litters at weaning had higher disease incidence, and disease incidence reduced as litter parity of the doe increased (P<0.05), when the disease trait was measured at week 9 and 10, but not for earlier weeks. Genetic correlations between disease incidence and mortality were imprecise and not different from zero. Phenotypic correlations were low to moderate, and positive. Although the mechanism at this stage is unknown, these findings suggest that there are common/shared immunological responses to bacterial challenge that are under genetic control. This study demonstrates that observed signs of bacterial infection in rabbits can be used as an indicator trait for resistance to bacterial infection, and the heritability of the trait is high enough to warrant further evaluation of the merit of including it in a breeding program. From one week to the next, rabbits exhibiting disease symptoms were more likely (10 to 50 times depending on week of measurement) to die than those that were healthy. The relative economic value of resistance to bacterial infection could be based on the relationship between disease incidence and survival, as well as the direct costs of effective disease control and treatment. (C) 2007 Elsevier B.V. All rights reserved.

The number of eggs from gastrointestinal nematodes per gram of faeces (worm egg count WEC) is commonly used to determine the need for anti-parasite treatments and the breeding value of animals when selecting for worm resistance. Diarrhoea increases faecal moisture and may dilute the number of worm eggs observed. To quantify this effect, egg counts in sheep at pasture were simulated by dosing 15 animals with chromic oxide particles. The simulated WEC diminished as faecal moisture increased. When faeces were dried, simulated WEC per unit dry matter was not influenced by the amount of faecal moisture present prior to drying. The results suggest that adjustment for faecal moisture may provide an improved estimate of FEC. Drying faeces to calculate the WEC per unit dry matter would provide such an adjustment but may not be practical for industry application. In the past, the CSIRO McMaster Laboratory has used an adjustment factor developed by Gordon based on the classification of faecal consistency derived from the morphology of faeces. To examine the utility of an adjustment factor based on faecal consistency score (FCS), the relationships between FCS and simulated WEC and dry matter were examined. Dry matter and simulated WEC exhibited an exponential decline as FCS increased. The relationship between FCS and dry matter was further examined in 368 samples collected over 12 months from sheep at pasture, where it was observed that dry matter showed a linear decline as FCS increased. Adjustment factors based on dry matter were similar to those proposed by Gordon however adjustment factors predicted from simulated WEC diverged from the remainder for FCS>4. As no samples scored FCS 5 in the study of simulated FEC, the adjustment factors based on the larger study that included samples with FCS 5 was therefore considered more robust. Adjustment factors were given by the equation: WECestimated=(WECobserved/(34.21−5.15 FCS))×29.06. This equation estimates for samples with FCS>1 the WEC that would be expected if the samples were FCS 1, the faecal consistency score for normal faeces. The impact of adjustment of observed WEC for faecal moisture predicted by FCS on decision points for treatment and on estimated breeding values requires further examination.

There has been an increasing focus on the role of antioxidants for human health. This review outlines associations of the most predominant antioxidant, glutathione (GSH), in the body and some ageing-related diseases. Strategies to replete GSH, particularly developing animal-source food products, are discussed. Potentials to alter GSH content in the animal's body and its possible effects on health are also explored.

This trial aimed to determine the relationship between faecal egg count (FEC) and scouring (diarrhoea), as measured by dag score (DS) and whether any genotype x environment interaction may exist for these traits tested in a summer and winter rainfall region. Significant differences were found in DS patterns between the 2 sites. In the summer rainfall environment, DS remained relatively constant throughout the year. In the winter rainfall environment, DS increased rapidly during the late winter and spring period in 1-year-old sheep. It is recommended that in the winter rainfall environment sheep should be selected for both low FEC and low DS.

Genetic selection for resistance to Haemonchus contortus, an experimental vaccine and protein supplementation were compared with a strategic anthelmintic drenching program in a factorial grazing experiment to determine their effect on nematode faecal egg count (FEC) of young Merino sheep. Averaged over a 224-day period, FECs were reduced 69% by genetic selection (P<0.001), 35% by protein supplementation (P<0.001), 28% by drenching (P<0.01) and were unaffected by vaccination. FECs in undrenched selected sheep were lower than strategically drenched unselected sheep. Liveweight gain was decreased by vaccination (13%, P<0.05) and increased by supplementation (44%, P<0.001). Fleece traits were significantly different (P<0.01) between the two genotypes with the selected line having a lower fibre diameter (0.6 μm, P<0.01) and producing 9% less clean wool than the random line (P<0.001). Supplemented animals grew more clean wool (17%, P<0.001) with a broader fibre diameter (1.1 μm, P<0.001). No important interactions between the various treatments were detected. Monitor sheep, run in the plots after the termination of the experiment, had significantly lower FECs (P<0.001) when run in plots previously grazed by supplemented sheep and selected sheep (on average 35% and 46% lower, respectively, compared to plots previously grazed by unsupplemented and random sheep). The results indicate that the largest and most persistent effect on FEC in the host, and worm contamination on pasture, was achieved by genetic selection.

This paper reviews experiments investigating the responses of resistant and susceptible genotypes of sheep to gastrointestinal nematode infection under differential nutrition. Using faecal egg count as a measure of host resistance, differences between genotypes appeared to be greatest under conditions of low nutrient availability and under such conditions both resistant and susceptible genotypes generally responded to supplemental protein by reducing faecal egg count. However, when nutritional conditions were moderate to good, responses to additional protein tended to be observed only in susceptible genotypes. In general, host genetic resistance was associated with reliable reductions in faecal egg count of moderate to large magnitude, while nutritional intervention was less reliable at reducing faecal egg count, and induced reductions of smaller magnitude. The situation was very different when examining host resilience to infection, as determined by sheep productivity in the face of infection. Increased host resistance was rarely associated with improved growth or production during the period of infection. In contrast, nutritional supplementation reliably increased host productivity irrespective of infection status and prevailing nutritional conditions. A general model of the relationship between nutrient availability and host resistance and resilience in resistant and susceptible genotypes is postulated. Taken together, the studies reviewed in this paper suggest that selection for host resistance and strategic nutritional intervention have complementary roles in the integrated control of gastrointestinal nematode infection in sheep. The former will contribute primarily to the epidemiology of the disease by reliably reducing faecal egg output over a wide range of conditions, reducing host challenge and the number of treatment interventions required. The latter will reliably boost host resilience to infection, with lesser effects on resistance, and the economic rationale for use will require accounting for the full spectrum of production and disease responses.

Data from 3 rabbit breeds, namely New Zealand White (N), Californian (C), and Flemish Giant (F), and their crosses, i.e. CN, FN, F(CN), and C(FN), were analysed for individual growth traits such as body weights at 5 (5WT), 6 (6WT), 7 (7WT), 8 (8WT), 9 (9WT), and 10 (10WT) weeks of age, and post-weaning average daily gain between 5 and 10 weeks of age (ADG), and individual slaughter traits such as liveweight at slaughter (SW), carcass weight (CW), and dressing percentage (DP). Data included records for individual body weights from 1345 to 1524 rabbits from 279 litters and records for slaughter traits from 919 rabbits from 245 litters. Significant sources of variation for individual growth and slaughter traits were breed, parity, month-year of birth, sex, and number weaned per litter (NW). However, parity and NW did not significantly affect ADG and DP. Slaughter traits were not significantly affected by sex. The overall least squares means for 5WT, 6WT, 7WT, 8WT, 9WT, 10WT, ADG, SW, CW, and DP were 836 g, 1021 g, 1215 g, 1390 g, 1577 g, 1791 g, 27.2 g/day, 2.28 kg, 1.23 kg, and 53% respectively. N and F purebred, and FN crossbred rabbits performed significantly (P < 0.05) better than C purebred and crossbreds [CN and C(FN)] in all the individual growth and slaughter traits except for DP. CN performed better (P�<�0.05) in DP than all other crosses. ADG of C rabbits was significantly (P < 0.05) lower than of all other crosses under study, with F(CN), C(FN), and CN crosses showing intermediate growth rates. Significantly (P < 0.05) higher growth rates were observed in N, F, and FN breeds. There was no significant heterosis observed in the breed crosses for any traits under study. Individual body weights at 5–10 weeks of age were significantly lower in the 1st parity born rabbits than in other higher parity born rabbits. SW and CW were significantly higher in 2nd and 3rd parity rabbits than in 1st and 4th and later parity born rabbits. Female rabbits achieved heavier weights at 5, 6, and 7 weeks of age than males and males weighed more than females after 7 weeks of age. ADG of males was significantly (P�<�0.05) higher than of females. Significant negative regression coefficients of NW on all individual body weights until slaughter age showed that larger litters had lighter rabbits. Coefficient of variation for individual growth and slaughter traits ranged between 11.1 and 20.7%. Common litter variance explained a significantly large proportion of total phenotypic variance, with the proportions ranging between 0.36 and 0.55 for individual growth traits, 0.46 for SW, and 0.35 for CW.

The ability to demonstrate a genetic trend is a powerful tool for enhancing adoption of advanced breeding programs. Over the last 6 years, a number of ram breeders have introduced selection for worm resistance into their breeding programs. This paper examines genetic trends in faecal egg count in two studs, one Merino and one Border Leicester. In the two studs that provided data for this paper, improvements in production traits were made and maintained when worm-resistance measurements were incorporated. In the Merino stud, hogget greasy fleece weight and body weight increased over the 7 years of study, and fibre diameter decreased by over half a micron. Overall the genetic trend for faecal egg count was negative. In the Border Leicester stud, large improvements were made in yearling body weight, and further favourable improvements were made in maternal weaning weight. Eye-muscle depth has remained relatively unchanged over the last 7 years. The genetic trend for faecal egg count has decreased and remained negative since selection pressure has been applied to this trait. The results obtained on both of these properties are encouraging for breeders who wish to simultaneously improve resistance to worms while making gains in production traits.

Data from a rabbit breeding experiment were analysed to compare the doe reproductive and pre-weaning litter performance of 3 breeds of rabbits, namely New Zealand White (N), Californian (C), and Flemish Giant (F), and their crosses CN (C × N) and FN (F × N). The foundation stock of 152 rabbits was collected from 26 different sources in New South Wales, Australia. Data on reproductive traits, doe age at first successful mating (DA), doe weight at first successful mating (DW) arising from 104 does, conception rate (CR) from 808 matings, and kindling interval (KI) from 325 records of 119 does were analysed. Overall means for reproductive traits DA, DW, CR, and KI were 21 weeks, 3.6 kg, 0.75, and 7.4 weeks, respectively. DA, CR, and KI did not differ significantly among different breeds and their crosses. DW of C does was found to be significantly lighter than all other breed crosses in the study. Month–year of mating significantly affected DA, DW, and CR (P < 0.01), and as the parity number increased, there was a significant (P < 0.01) decrease in KI. As age of the doe at mating increased there was a significant increase in DW (P < 0.01), CR (P < 0.05), and KI (P < 0.01). Data from 436 litters of 157 does were included in the analysis of pre-weaning litter traits. The overall means for the pre-weaning litter traits were: number born per litter (NB, 8.1), number born alive per litter (NBA, 6.9), number weaned per litter (NW, 3.3), total litter birth weight (TLBW, 453.7 g), live litter birth weight (LLBW, 397.1 g), litter weaning weight (LWW, 2.8 kg), and average birth weight of kits per litter (ABW, 58.1 g). Doe breed significantly affected NW (P < 0.05), TLBW (P <�0.01), LLBW (P < 0.05), LWW, and ABW (P < 0.01). N does and crossbred does (CN and FN) performed better than purebred F and C does for NW and LWW. A significant heterosis of 41.9% and 40.8% was observed in CN does for traits NW and LWW, respectively. ABW of F does was significantly higher than that of all other breed crosses in the study. Buck breed did not have any significant effect on any of the pre-weaning litter traits under study. Parity significantly affected NW (P < 0.05), TLBW (P < 0.01), LLBW (P < 0.05), and ABW (P < 0.01). First parity does produced litters with significantly lighter birth weights. The month–year of birth effect was significant for NW, LWW (P < 0.01), and ABW (P < 0.05).�The coefficients of variation for the doe reproductive traits and pre-weaning litter traits ranged between 12.1 and 59.5% and 16.1 and 93.3%, respectively. High phenotypic variances and coefficients of variation observed for traits NW and LWW indicate that good response could be realised through selection. Repeatability estimates for reproductive traits CR and KI were very low. Low to moderate repeatability estimates in the range 0.17–0.25 were observed for pre-weaning litter traits. Significant positive phenotypic correlations were observed between litter size and litter weight traits (0.30–0.97). A significant negative correlation was observed between ABW and NB (–0.56) and NBA (–0.36).

With the sustained decline in wild rabbits harvested for meat, rabbit farming has generated a lot of interest as a rural industry in Australia. A profit function was used to derive the economic values for various production traits of farmed rabbits. The mean values of the different variables affecting the profit function were taken from literature and from a rabbit farmer survey. The profit function was calculated as a deviation of costs from returns. Profit was considered as a function of several traits and the economic value of each of the traits was estimated as a partial derivative of the profit function. As this new industry develops and mean production values improve, these preliminary estimates of economic values should be reviewed. The most common problems identified by farmers were high feed cost, disease and slow growth rate.