The clinical expression of multiple-strain infections has implications for both research and control of footrot. A novel method of control is proposed.

Goat meat production is an expanding industry in Australia. However, there is limited data quantifying the levels of reproductive performance, particularly under extensively grazed rangeland conditions, which would inform interventions to improve performance. This review aimed to quantify the levels of reproduction, time and causes of reproductive wastage in goats. It considers the levels of fertility, fecundity, embryonic loss, fetal loss and post-natal survival reported under Australian conditions, and comparisons are made with international reports. Key management factors that may contribute to reproductive performance include breed, seasonality, nutritional conditions, and weather conditions at kidding. While goats are potentially prolific breeders, in Australia, the variation in weaning rate (kids/doe joined) among properties is large (51–165%), although the causes of this variation are not well defined. Generally, conception and kidding rates are high, although fetal loss associated with undernutrition is more likely in goats than sheep. As with sheep, perinatal losses are generally the largest source of wastage, with an average 20% kid mortality, but this level is influenced by litter size and appears to be higher under extensive rangeland systems. The causes of perinatal kid loss under Australian conditions are similar to those in sheep, with starvation–mismothering–exposure and dystocia or stillbirth the key causes. Studies are needed to accurately quantify the level and causes of reproductive wastage in commercial herds, including a range of management situations, to enable effective interventions to be developed.

Objective Compare footbathing and vaccination for control of footrot during a transmission period in a sheep flock deliberately infected with multiple strains of Dichelobacter nodosus. Methods The strains included a known virulent strain, a benign strain and several intermediate strains. The resulting footrot was clinically intermediate. A total of 1450 Polwarth sheep aged 1–3 years were allocated to one of five treatment groups: untreated, weekly walkthrough zinc sulfate footbathing, 1‐hour stand‐in Footrite® footbathing every 3 weeks, vaccination with a commercial multivalent whole‐cell vaccine and vaccination with a novel recombinant DNA fimbrial vaccine. There were four replicates, in four paddocks. Results Of the untreated animals, 76% had footrot. Footbathing, either weekly or every 3 weeks, restricted the prevalence to 6/283 (2%; 97% effective) and 18/275 (6.5%; 91% effective), respectively. This was significantly lower than the prevalence in either the untreated or vaccinated group (P < 0.001). Weekly footbathing resulted in significantly fewer affected sheep than footbathing for 1 h every 3 weeks (P < 0.05). Vaccination with either whole‐cell or recombinant vaccines significantly (P < 0.001) reduced the prevalence ((142/280 (51%; 33% effective), 114/278 (41%; 46% effective) respectively), with the recombinant vaccine superior (P < 0.05) to whole‐cell vaccination. Significantly (P < 0.05) fewer 1‐year‐old sheep had footrot than older sheep. A single Footrite treatment reduced the prevalence to 12% (53/445) compared with a prevalence of 57% (27/47) for untreated sheep (79% effective). Conclusion In this study footbathing was more effective than vaccination at controlling and treating multistrain footrot.

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Perinatal lamb mortality is a major challenge for sheep producers worldwide. Lamb losses from ultrasound pregnancy scanning to lamb marking were assessed in 125 mobs of ewes sourced predominantly from sheep flocks in southern New South Wales. In total, 103 086 lambs were marked from100 165 ewes present at joining. Despite the majority of producers undertaking best-practice ewe management, including ultrasound scanning for pregnancy and preferential feeding of multiple bearing ewes, losses were similar to those reported previously (11% and 29% for singles and twins respectively). Non-Merino ewes had significantly lower losses than did Merino ewes, irrespective of ram type (13% versus 21%, P < 0.001). There was a tendency for mob size in twin-bearing ewes to influence survival, with a lower mob size (<200) having lower losses (29% versus 33%, P = 0.07). These results are discussed in the context of existing extension advice about ewe management and perinatal lamb mortality.