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Sheep and goats have been produced in Fiji from as early as the 1840s and the country currently has the largest small ruminant production of all Pacific Island Countries. The first local research on small ruminants started in the 1950s. Over the decades the small ruminant production systems have been influenced by numerous challenges but remained an integral part of agricultural production systems in Fiji.

A database search was performed to better understand technologies tested and developed in local small ruminant research activities. Historic literature reviews and additional grey literature were considered additionally. The available published literature was systematically reviewed identifying technologies that have been adopted and persisted over time. Factors fostering or constraining their adoption were assessed. In addition, several key informant interviews revealed current challenges and developments of small ruminant research, and extension, in Fiji.

Four main drivers of the institutional environment for small ruminant research in Fiji have been identified. Among them, the Ministry of Agriculture of Fiji has traditionally been a proponent of small ruminant research to this day. Its efficiency in delivering research outcomes has fluctuated greatly over time.

Results revealed that key production system aspects have also been the focal areas of small ruminant research in Fiji with a strong focus on gastro-intestinal parasite management, breeding and forage development. The development of the Fiji Fantastic sheep breed has been a concerted success of the research and extension system and remains of great importance.

Conclusions from the literature review and key informant interviews include that many of the current challenges have remained unchanged since the beginning of small ruminant production in Fiji. The government is trying to find new ways to support the development of the local small ruminant sector. An aging farming population, the status of small ruminant production compared to other agricultural activities, low accessibility of small ruminant technologies and traditional land lease systems remain substantial impediments.

In this paper, we discuss the theory behind calibration curve experiments and their application to a zinc (Zn) bioavailability study with broiler chickens. Seven replicates of 16 male commercial broiler chicks were fed starter diets for 14 days. Six diets had different levels of a potential Zn source and one was a positive control with standard industry levels of Zn for comparison. Four commonly used methods of calculating bioavailability means and confidence intervals (CI) from a calibration curve (standard curve) experiment to estimate the bioavailability of a new zinc source in broiler chickens were compared. The methods compared were the following: 1) the Counter-Intuitive Method uses a multiple-range test to compare unknown test and standard samples; 2) the Intuitive Method uses standard linear regression and inverts the equation to predict Zn bioavailability for each replicate of test samples; 3) the Abductive Method uses Graybill's Equation, based on theory and observation, to estimate CI's; and 4) the Sophistic Method uses reverse regression, and calculates Zn bioavailability values directly from the equation. The Counter-Intuitive Method only gives information about which standards the test samples are, or are not, significantly different from respectively (average available Zn not predicted). The Intuitive Method ignores error about the standard curve and theoretically cannot estimate the CI directly (X̄±SEM = 107.5 ± 15.8 mg Zn/kg). The Sophistic Method underestimates and overestimates the test sample mean values above and below the mean of the standards, respectively (X̄ = 96.6 mg Zn/kg). The Abductive Method has an advantage over the other methods: The mean prediction estimation is consistent with theory (107.5 ± 6.1 mg Zn/kg; X̄±SEM). When test or "unknown" samples are near the mean of the standard samples, the CI is smaller than when near the extremes of the calibration curve. When calibration curve error is small (R² > approximately 0.95), there is little advantage to using the Abductive Method, but when calibration curve error is larger, as in many bioassays with growing animals, the Abductive Method improves the accuracy of the CI calculations. The Abductive Method was used to demonstrate the influence of the number of replicate samples on experimental power and cost.

The objective of this study was to compare the accuracies of genomic prediction for milk yield, fat yield, and protein yield from Philippine dairy buffaloes using genomic best linear unbiased prediction (GBLUP) and single-step GBLUP (ssGBLUP) with the accuracies based on pedigree BLUP (pBLUP). To also assess the bias of the prediction, the regression coefficient (slope) of the adjusted phenotypes on the predicted breeding values (BVs) was also calculated. Two data sets were analyzed. The GENO data consisting of all female buffaloes that have both phenotypes and genotypes (n = 904 with 1,773,305-days lactation records) were analyzed using pBLUP and GBLUP. The ALL data, consisting of the GENO data plus females with phenotypes but not genotyped (n = 1,975 with 3,821,305-days lactation records), were analyzed using pBLUP and ssGBLUP. Animals were genotyped with the Affymetrix 90k buffalo genotyping array. After quality control, 60,827 single-nucleotide polymorphisms were used for downward analysis. A pedigree file containing 2,642 animals was used for pBLUP and ssGBLUP. Accuracy of prediction was calculated as the correlation between the predicted BVs of the test set and adjusted phenotypes, which were corrected for fixed effects, divided by the square root of the heritability of the trait, corrected for the number of lactations used in the test set. To assess the bias of the prediction, the regression coefficient (slope) of the adjusted phenotypes on the predicted BVs was also calculated. Results showed that genomic methods (GBLUP and ssGBLUP) provide more accurate predictions compared to pBLUP. Average GBLUP and ssGBLUP accuracies were 0.24 and 0.29, respectively, whereas average pBLUP accuracies (for GENO and ALL data) were 0.21 and 0.22, respectively. Slopes of the two genomic methods were also closer to one, indicating lesser bias, compared to pBLUP. Average GBLUP and ssGBLUP slopes were 0.89 and 0.84, respectively, whereas the average pBLUP (for GENO and ALL data) slopes were 0.80 and 0.54, respectively.

Background Hoof structure and health are essential for the welfare and productivity of beef cattle. Therefore, we assessed the genetic and genomic background of foot score traits in American (US) and Australian (AU) Angus cattle and investigated the feasibility of performing genomic evaluations combining data for foot score traits recorded in US and AU Angus cattle. The traits evaluated were foot angle (FA) and claw set (CS). In total, 109,294 and ~1.12 million animals had phenotypic and genomic information, respectively. Four sets of analyses were performed: (1) genomic connectedness between US and AU Angus cattle populations and population structure, (2) estimation of genetic parameters, (3) single-step genomic prediction of breeding values, and (4) single-step genome-wide association studies for FA and CS.

Results There was no clear genetic differentiation between US and AU Angus populations. Similar heritability estimates (FA: 0.22–0.24 and CS: 0.22–0.27) and moderate-to-high genetic correlations between US and AU foot scores (FA: 0.61 and CS: 0.76) were obtained. A joint-genomic prediction using data from both populations outperformed within-country genomic evaluations. A genomic prediction model considering US and AU datasets as a single population performed similarly to the scenario accounting for genotype-by-environment interactions (i.e., multiple-trait model considering US and AU records as different traits), even though the genetic correlations between countries were lower than 0.80. Common signifcant genomic regions were observed between US and AU for FA and CS. Signifcant single nucleotide polymorphisms were identifed on the Bos taurus (BTA) chromosomes BTA1, BTA5, BTA11, BTA13, BTA19, BTA20, and BTA23. The candidate genes identified were primarily from growth factor gene families, including FGF12 and GDF5, which were previously associated with bone structure and repair.

Conclusions This study presents comprehensive population structure and genetic and genomic analyses of foot scores in US and AU Angus cattle populations, which are essential for optimizing the implementation of genomic selection for improved foot scores in Angus cattle breeding programs. We have also identified candidate genes associated with foot scores in the largest Angus cattle populations in the world and made recommendations for genomic evaluations for improved foot score traits in the US and AU.

Ruminants are significant contributors to the livestock generated component of the greenhouse gas, methane (CH₄). The CH₄ is primarily produced by the rumen microbes. Although the composition of the diet and animal intake amount have the largest effect on CH₄ production and yield (CH₄ production/dry matter intake, DMI), the host also influences CH₄ yield. Shorter rumen feed mean retention time (MRT) is associated with higher dry matter intake and lower CH₄ yield, but the molecular mechanism(s) by which the host affects CH₄ production remain unclear. We integrated rumen wall transcriptome data and CH₄ phenotypes from two independent experiments conducted with sheep in Australia (AUS, n = 62) and New Zealand (NZ, n = 24). The inclusion of the AUS data validated the previously identified clusters and gene sets representing rumen epithelial, metabolic and muscular functions. In addition, the expression of the cell cycle genes as a group was consistently positively correlated with acetate and butyrate concentrations (p < 0.05, based on AUS and NZ data together). The expression of a group of metabolic genes showed positive correlations in both AUS and NZ datasets with CH₄ production (p < 0.05) and yield (p < 0.01). These genes encode key enzymes in the ketone body synthesis pathway and included members of the poorly characterized aldo-keto reductase 1C (AKR1C ) family. Several AKR1C family genes appear to have ruminant specific evolution patterns, supporting their specialized roles in the ruminants. Combining differential gene expression in the rumen wall muscle of the shortest and longest MRT AUS animals (no data available for the NZ animals) with correlation and network analysis, we identified a set of rumen muscle genes involved in cell junctions as potential regulators of MRT, presumably by influencing contraction rates of the smooth muscle component of the rumen wall. Higher rumen expression of these genes, including SYNPO (synaptopodin, p < 0.01) and NEXN (nexilin, p < 0.05), was associated with lower CH₄ yield in both AUS and NZ datasets. Unlike the metabolic genes, the variations in the expression of which may reflect the availability of rumen metabolites, the muscle genes are currently our best candidates for causal genes that influence CH₄ yield.

As the world warms, understanding the fundamental mechanisms available to organisms to protect themselves from thermal stress is becoming ever more important. Heat shock proteins are highly conserved molecular chaperones which serve to maintain cellular processes during stress, including thermal extremes. Developing animals may be particularly vulnerable to elevated temperatures, but the relevance of heat shock proteins for developing altricial birds exposed to a thermal stressor has never been investigated. Here, we sought to test whether three stress-induced genes – HSPD1, HSPA2, HSP90AA1 – and two constitutively expressed genes – HSPA8, HSP90B1 – are upregulated in response to acute thermal shock in zebra finch (Taeniopygia guttata) embryos half-way through incubation. Tested on a gradient from 37.5 ◦C (control) to 45 ◦C, we found that all genes, except HSPD1, were upregulated. However, not all genes initiated upregulation at the same temperature. For all genes, the best fitting model included a correlate of developmental stage that, although it was never significant after multiple-test correction, hints that heat shock protein upregulation might increase through embryonic development. Together, these results show that altricial avian embryos are capable of upregulating a known protective mechanism against thermal stress, and suggest that these highly conserved cellular mechanisms may be a vital component of early developmental protection under climate change.

Context. The anticoagulant properties of heparin have led to the routine use of heparinised saline flushes to prevent thrombus formation and to prolong the patency of indwelling cannulas. However, limited work exists on very low-dose heparin used to retain cannula patency for the purpose of repeated blood sampling for metabolic studies. Of particular interest is whether low-dose heparin will cause increases in plasma non-esterified fatty acid (NEFA) concentration. This is most relevant in metabolic studies involving repeated sampling, as this may erroneously elevate apparent plasma NEFA concentrations.

Aims. The objective of the present study was to evaluate the impacts of low- and high-dose heparin administration on plasma NEFA response in lambs.

Methods. In total, 14 merino (3 female, 4 wether) and terminal (4 female, 3 wether) sired lambs were selected from the Katanning, Western Australia, site of the Meat and Livestock Australia genetic resource flock All lambs were subjected to the following three treatments: low heparin (0.25 mL, 250 IU), high heparin (1 mL, 1000 IU) or control (1 mL of 0.9% NaCl saline), with each challenge being randomly allocated over 1.5 days. Blood samples were collected at the following time points: –30, –15, –10, –5, 0, 2.5, 5, 10, 15, 20, 30, 45, 60, 90, 120, 125 and 130 min relative to the administration of the challenge (Time 0) and tested for NEFA concentration. A derived exponential function was fitted to the raw data, enabling the plasma NEFA concentration response curve to be modelled at different time points pre- and post-challenge, using the area under curve (AUC), maximum concentration and return to basal concentration, to quantify the NEFA response.

Results. Heparin-challenge dose had a significant (P < 0.01) impact on peak NEFA response at 10 min following challenge administration (NEFA AUC10), with the values after high-heparin challenge (1.03 ± 0.086 mmol/L per 10 min) being ~25% higher (P < 0.05) than those after the low-heparin challenge (0.78 ± 0.086 mmol/L per 10 min). The NEFA AUC10 values with low-dose heparin and high-dose heparin were 0.76 units and 1.02 units higher than those with the saline treatment (0.02 ± 0.086 mmol/L per 10 min; P < 0.01). Heparin-challenge dose also had a significant impact on the maximum NEFA concentration (P < 0.05). The high-heparin challenge (0.32 ± 0.057 mmol/L) had 20% higher maximum NEFA concentrations than the low-heparin challenge (0.26 ± 0.057 mmol/L). Both high and low heparin-challenge groups had maximum NEFA concentrations that were 72% and 36% higher respectively, than for the saline-challenge (0.19 ± 0.057 mmol/L) group. NEFA returned to basal concentrations by 60 min for both challenges, although the high heparin-challenge group demonstrated a slower rate of return (P < 0.05).

Conclusions. High and low doses of heparin caused an increase in plasma NEFA response as measured by AUC10 and maximum NEFA concentration, but returned to basal concentrations within 1 h.

Implications.Results indicated that heparin as an anticoagulant should be avoided where frequent blood samples are required within intervals of less than 1 h. However, for repeated sampling at intervals greater than 1 h, judicious flushing with heparinised saline is unlikely to have an impact on plasma NEFA concentrations.

In agricultural research for development adoption of new technology tends to be cast in categories: adoption, partial adoption, dis-adoption or non-adoption. While these may serve for pragmatic classification and measures for project success or impact they fail to properly acknowledge the ongoing and independent efforts of farmers (and others) in experimentation and integration of knowledge across a range of sources. This paper explores responses to practices for cattle management introduced during a research project, at project close, and five years after the project has finished. We consider the perceptions and application of new knowledge by farmers, extension staff, and policy makers. By taking a longer-term view, we demonstrate how farming households adapt and integrate knowledge from different sources into their daily practice, influenced by local institutions and changing cultural expectations, as well as external researchers. We also consider the influence of changing government priorities and incentives in steering farm-management decisions. Results suggest that a focus on measures to build capacity and empower farmers with information to adapt and respond to change, regardless of project activities, is a much more important goal and indicator of impact than measuring adoption.

Cattle fattening using Leucaena (Leucaena leucocephala) as the source or the main component of the cattle's diets is one of the proven innovations that can provide financial benefit to cattle farmers. The objective of this study is to evaluate the adoption of Leucaena-based cattle fattening and identify the factors contributing to the adoption and diffusion of these improved practices. A mixed method approach was used to understand the adoption of Leucaena and cattle management by local farmers who participated in the early stage (2017) and those who participated in the later stages of the project (2018– 2020). The study showed that male Bali cattle (Bos javanicus) that were fed Leucaena-based diets grew two times faster than cattle fattened on grasses. This increased live weight gain and, subsequently, faster sales and increased profits. This may account for the rapid adoption and diffusion of Leucaenabased cattle fattening in Dompu through farmer-to-farmer learning, effective facilitation, demonstration trials, and linking farmers to end markets. To sustain the practice change, the project facilitated the development of an agribusiness support center (ASC). Sustaining the ASC requires further efforts that include internalization of the project outcome into the local government program.

Animal production is a significant protein source for human consumption (Salter and Lopez-Viso, 2021). The production of monogastric animals has grown enormously in recent decades, particularly of poultry and swine (Rauw et al., 2020). Such growth is attributed to the progress in animal nutrition, disease control, and genetic improvement in response to the global demand for meat (Kumar et al., 2023) and, of course, the tireless efforts of scientists working in the area for the past decades. Among them is Professor Mingan Choct, a monogastric animal nutritionist at the University of New England. He has dedicated his entire academic career to the field, significantly contributing to monogastric animal research and industry. To honour his contribution and celebrate his retirement, we organized a special issue in Animal Nutrition with contributions from a group of prominent researchers in monogastric animal nutrition and health. In this special issue, we published reviews and research papers, 8 in total, with a focus on the nutrition and health of monogastric production animals.

Prebiotics are non-digestible carbohydrates that selectively stimulate the growth of beneficial bacteria. Prebiotic supplementation into poultry diets results in a decreased rate of pathogenic bacteria colonisation in the gastrointestinal tract. It also enhances production of volatile fatty acids and lactic acid, which provide the bird with energy. This results in improved host gastrointestinal health and productive performance. Oligosaccharides are the most notable prebiotics in poultry nutrition. Examples of prebiotic oligosaccharides include xylo-oligosaccharides, fructooligosaccharides, and galacto-oligosaccharides. Oligosaccharides are derived from hydrolysis of non-starch polysaccharides (NSP). They are manufactured from plant sources, synthesised by physiochemical methods or enzymatic processes. The effects of oligosaccharides occur primarily in the caeca" oligosaccharides bypass the small intestine and reach the caeca, where they are readily fermented by beneficial bacteria, such as those in family Lactobacillaceae and Bifidobacteriaceae. Caeca function is generally poorly understood, despite extensive reviews and studies in this field. A deeper understanding of the factors that influence ability of the caeca to effectively utilise oligosaccharides is warranted. This would allow new prebiotic products and NSP- degrading enzymes to be developed, targeted to specific diets and scenarios. This is required, given the lack of consistency observed in the outputs derived from different studies assessing oligosaccharide efficacy in poultry diets. A key hinderance to progression in this field is that authors rarely analyse the oligosaccharide content and composition in the test diets and products, or in the bird's gastrointestinal tract. This review examines the mechanisms behind how oligosaccharides induce prebiotic effects in poultry, by identifying the role of the caeca in NSP digestion and identifying the impact of oligosaccharides on caeca microbiota and short-chain fatty acid composition.

We are pleased to present the third Special Issue (SI) published in the International Journal of Biometeorology dedicated to highlighting research conducted by members of the Students and New Professionals (SNP) within the International Society of Biometeorology (ISB).

A modified AM/PM strategy was evaluated in this study by supplementing calcium (Ca) in afternoon/evening (PM) drinking water instead of feed, offering an alternative to supplying two diets. A 10-week trial was conducted with 288 Hy-Line Brown hens (56 weeks old) housed on the floor in 18 pens (16 hens per pen; 9 replicate pens per treatment). The control diet contained 4.5% Ca, while the AM/PM treatment had 4.1% in feed with additional Ca and vitamin D supplemented through PM drinking water, with other nutrients kept constant in both diets. Daily egg production and weekly feed and water consumption were recorded. Hen weight, welfare scores, and egg quality were assessed at weeks 5 and 10. Blood, ileal digesta, and tibia samples were collected (from 4 hens/pen) at week 10 for serum Ca and vitamin D, digestibility, and bone analyses. Liver and kidney weights, as well as keel bone scores, were also recorded at week 10. Hens on the AM/PM diet consumed significantly less water (171.23 vs. 196.85 mL/bird/day; p < 0.001) and had a significantly higher serum vitamin D (27.59 vs. 22.64 ng/mL; p = 0.014), with a tendency towards elevated serum calcium levels (31.99 vs. 29.74 mg/dL; p = 0.089) compared to the control group. No differences in laying performance, co-efficient of variance (CV%) in individual hen and egg weight, liver and kidney weight, or keel and tibia characteristics were observed between treatments (p > 0.05). Similarly, there was no treatment effect on egg quality, and welfare parameters at week 5 and 10, except for smaller eggs (57.13 vs. 57.96; p = 0.015), and reduced chest (0.96 vs. 1.16; p = 0.028) and belly feather damage (1.34 vs. 1.55; p = 0.021), respectively, in hens of the AM/PM treatment compared to the control at week 10. The AM/PM treatment improved ileal digestible energy as is (9.00 vs. 8.22; p = 0.022) and as dry matter (10.00 vs. 9.06; p = 0.014) compared to the control one. Overall, it demonstrated comparable performance to the control, with added benefits of reduced water intake, better feather condition and vitamin D level and energy digestibility.

Meat colour is an important attribute for consumer acceptance but there is an interval between colour grading and retail display. This experiment investigates the effect of time post-slaughter (5, 14 and 40 days) on colour and bloom depth (after 1 and 24 h) for beef carcasses graded AUS-MEAT colour 4 (MC 4). Sixteen carcasses were selected at grading, 8 carcasses were graded MC 4 and 8 as compliant colour (AUS-MEAT score 2 or 3). At 5 days post-slaughter, compliant loins had greater overall bloom depth and were more red than MC 4 loins. Bloom depth (24 h) increased with ageing time but reached maximum bloom at 14 days for both treatments. After ageing for 14 and 40 days, the bloom depth of MC 4 loin was no different to the 5 day aged compliant loins after 24 h on display. Colour at grading may not be a reliable measure of retail colour considering the changes post slaughter.

This AgGuide, Products of the hive, is about more than honey production. The complex behaviour of bees results in other products such as wax, pollen, propolis, royal jelly and, for older bees, bee venom. There is a range of possibilities for beekeepers to consider when it comes to overall profitability of keeping honey bees.

This book has been compiled for experienced beekeepers to give them ideas about how they might diversify their income from beekeeping activities. It has also been written for those who have a general interest and fascination with the art and pleasure of beekeeping. It includes an account of increased knowledge about the bioactivity of honey.

To determine the effectiveness of propofol alone (P), and the combination of xylazine-propofol (XP), xylazine-ketamine (XK), xylazine-thiopentone (XT), anaesthetic protocols were studied in randomly selected 16 healthyindigenous pigs of either sexes, age 12 to 15 months and weight ranging from 12 to 16 kg. The responses ofpropofol and the combinations in different stages of anaesthesia were closely monitored. Various reflex responsesand muscle tenacity were also observed concurrently during the period of anaesthesia. The study found the shortest(0.29±0.02 min) induction period with XT anaesthesia and the longest (2.95±0.21 min) by XK" whereas, inductionof anaesthesia with P and XP was 0.4±0.08 and 0.41±0.08 min respectively. The time required for maximum depthof anaesthesia was the shortest in P (7.50±0.65 min) than the combinations. However, the anaesthetic protocol withXP produced the highest (65.25±3.30 min) duration of anaesthesia than the shortest (10.75±1.75 min) extent withP. Moreover, time to recovery from anaesthesia was higher (83.25±2.14 min) in XT and shorter (18.50±1.32 min)in P protocol. Good muscle relaxation was observed in XP, XK and XT combinations. Palpebral, conjunctival, jaw,tail and digital reflexes were almost absent in XP and XT combinations. The study concluded that propofol itself isa safe anaesthetic for short surgical interventions and its combination with xylazine is to be recommended forprolonged surgical procedures in swine.

Background The effects of environmental disturbances on livestock are often observed indirectly through the variability patterns of repeated performance records over time. Sheep are frequently exposed to diverse extensive environments but currently lack appropriate measures of resilience (or sensitivity) towards environmental disturbance. In this study, random regression models were used to analyse repeated records of the fbre diameter of wool taken along the wool staple (bundle of wool fbres) to investigate how the genetic and environmental variance of fbre diameter changes with different growing environments.

Results A model containing a fifth, fourth and second-order Legendre polynomial applied to the fixed, additive and permanent environmental effects, respectively, was optimal for modeling fbre diameter along the wool staple. The additive genetic and permanent environmental variance both showed variability across the staple length trajectory. The ranking of sire estimated breeding values (EBV) for fbre diameter was shown to change along the staple and the genetic correlations decreased as the distance between measurements along the staple increased. This result suggests that some genotypes were potentially more resilient towards the changes in the growing environment compared to others. In addition, the eigenfunctions of the random regression model implied the ability to change the fbre diameter trajectory to reduce its variability along the wool staple.

Conclusions These Results show that genetic variation in fbre diameter measured along the wool staple exists and this could be used to provide greater insight into the ability to select for resilience in extensively raised sheep populations.

Free-range egg production plays a key role in the global food system, and current market trends suggest that consumer demand for free-range eggs will continue to rise. Freerange egg production is susceptible to a wide range of factors, including climatic conditions, management practices, and disease presence. These factors can cause variability in the laying rate of a flock over time, leading to fluctuations in egg production. The main purpose of this study was to investigate the risk of short-term free-range egg production losses using data derived from a combination of sensing technologies and management activities. Production and environmental data were collected from a commercial farm comprising seven flocks of laying hens. The variables studied included laying rate, feed intake, water intake, solar radiation, humidity, precipitation, and indoor/outdoor temperature. These were processed into a set of aggregate features calculated across a 14-day moving window. Generalized estimating equations were used to analyze the association between the derived production and environmental features and the probability of a short-term drop in egg production, expressed through deviations in the laying rate on the day immediately following the data window. Odds ratios were used to express the relative risk of a production drop by comparing the features for window periods where production drops occur to the window periods where production drops did not occur. The results demonstrated that a range of data features based on the laying rate, feed intake, water intake, and indoor/outdoor temperatures all had significant associations with the odds of a production drop. Key findings from the study show that an increase in feed intake and laying rate measured across the 14-day data window were correlated with a lower risk of a sudden drop in egg production. Conversely, a low mean indoor temperature (x < 16.1 ◦C group), measured through environmental sensing data, was correlated with a higher risk of a sudden drop in egg production. This study quantifies the link between data features derived from production and environmental monitoring and egg production issues, thereby providing useful insights on the most important data items captured through day-to-day monitoring, which can be used for proactive management. Further research should be carried out to investigate how technologies such as machine learning and analytics platforms can be applied for the task of forecasting production interruptions using the data features explored in this study.

Measuring and mitigating methane (CH₄) emissions from livestock is of increasing importance for the environment and for policy making. Potentially, the most sustainable way of reducing enteric CH₄ emission from ruminants is through the estimation of genomic breeding values to facilitate genetic selection. There is potential for adopting genetic selection and in the future genomic selection, for reduced CH₄ emissions from ruminants. From this review it has been observed that both CH₄ emissions and production (g/day) are a heritable and repeatable trait. CH₄ emissions are strongly related to feed intake both in the short term (minutes to several hours) and over the medium term (days). When measured over the medium term, CH₄ yield (MY, g CH₄/kg dry matter intake) is a heritable and repeatable trait albeit with less genetic variation than for CH₄ emissions. CH₄ emissions of individual animals are moderately repeatable across diets, and across feeding levels, when measured in respiration chambers. Repeatability is lower when short term measurements are used, possibly due to variation in time and amount of feed ingested prior to the measurement. However, while repeated measurements add value" it is preferable the measures be separated by at least 3 to 14 days. This temporal separation of measurements needs to be investigated further. Given the above issue can be resolved, short term (over minutes to hours) measurements of CH₄ emissions show promise, especially on systems where animals are fed ad libitum and frequency of meals is high. However, we believe that for short-term measurements to be useful for genetic evaluation, a number (between 3 and 20) of measurements will be required over an extended period of time (weeks to months). There are opportunities for using short-term measurements in standardised feeding situations such as breath 'sniffers' attached to milking parlours or total mixed ration feeding bins, to measure CH₄. Genomic selection has the potential to reduce both CH₄ emissions and MY, but measurements on thousands of individuals will be required. This includes the need for combined resources across countries in an international effort, emphasising the need to acknowledge the impact of animal and production systems on measurement of the CH₄ trait during design of experiments.

The efficacy of commercially available anthelmintics against mature and immature stages (including ovicidal effects) of two Australian field isolates of Ascaridia galli was evaluated in two separate experiments. The anthelmintics tested were levamisole (LEV), piperazine (PIP) and flubendazole (FBZ) plus LEV-PIP. A total of 192 artificially trickle-infected young cockerels (96 birds per isolate) were randomized into sixteen experimental groups of 12 cockerels each (7 treatments and 1 untreated control per isolate). Chickens received label-recommended doses of LEV (28 mg/kg), PIP (100 mg/kg) or LEV-PIP co-administered at their full individual doses as a single oral dose or in group drinking water at recommended concentrations of 0.8 mg/ml or 2.5 mg/ml over eight hours for 1 and 2 days respectively and FLBZ (30 ppm) in the feed over 7 days. Anthelmintic efficacies were assessed by worm count reduction (WCR%) and excreta egg count reduction (EECR%) estimated by two methods. Ten days post treatment, all untreated control birds harboured mixed worm population of 10.1 and 12.3/bird for each isolate respectively which was significantly higher (P < 0.0001) than counts in all treatment groups. Luminal or histotrophic larvae comprised 50–57 % of the total worm count. For LEV, PIP and LEV-PIP, individual oral administration provided a somewhat higher efficacy than group medication in drinking water. EECR% values were inconsistent with WCR% and found to be only an indicator of efficacy against adult worms. All developmental stages of the two A. galli isolates were highly susceptible to FLBZ (100 %) followed by LEV-PIP (92.4–100 %) and LEV (87.7–100 %). PIP exhibited good efficacy against adult worms (92–97 %) but reduced efficacy against luminal (79–84 %) and histotrophic (61–72 %) larvae. Embryonation capacity of eggs recovered from worms expelled after treatment with LEV (47–54 %), PIP (44–54 %) or LEV-PIP (45–48 %) did not differ from those from untreated birds (50–51 %) whereas eggs from FLBZ treated worms had a significantly lower (P < 0.05) capacity to embryonate (≤ 2 %). Put together, our results demonstrate no evidence of resistance of the test A. galli isolates to the tested anthelmintics but a significant advantage of FLBZ, followed by LEV-PIP and LEV over PIP in the control of A. galli, specifically with regard to immature stages. A. galli worms expelled after treatment with LEV, PIP or their combination, but not FLBZ contain viable eggs. This has epidemiological implications and may also provide an option for isolating eggs from mature worms for A. galli propagation experiments without having to sacrifice birds.

Context. Herding and mustering procedures during livestock management can be time-consuming, labour intensive, and costly. The ability to gather animals virtually is an enticing notion but technology to do this is not widely commercially available.

Aims. The eShepherd® virtual fencing system being developed for cattle may be able to remotely herd animals. This system operates via global positioning system, and requires animals to wear a neckband device. Animals are trained to associate an audio tone with an electrical pulse to avoid a virtual boundary.

Methods. Experiments were conducted with cattle using pre-commercial prototypes of the automated virtual fencing neckbands, and with sheep using manually operated dog training collars implementing the same virtual fencing algorithm to explore the potential of this technology for herding, and optimal fence designs for herding success. In the first experiment, five groups of 12 cattle were moved down a 344 m paddock using three different fence placement designs.

Results. The most successful design for cattle herding was a back fence that followed behind the animals to prevent them from turning back in the wrong direction. The fences were manually activated by personnel based on the cattle movement. The same type of fence design was manually applied to two groups of six sheep to successfully herd them down a 140 m paddock in the second experiment

Conclusions.All herding was highly dependent on the animal’s own pace of movement as no signals were applied to ‘push’ the animals, the systems only prevented movement back in the wrong direction. The pre-commercial prototype of the automated eShepherd® device used is now obsolete and testing with updated versions would be needed to confirm its application for animal herding.

Implications. These preliminary trials indicate potential for virtual fencing technology to herd livestock, but technology improvements are required, and an automated device for sheep is not yet available.

In Cambodia, information on common pathogens causing reproductive losses in cattle and bufalo are lacking, despite there being a need to address livestock health to enhance food security. We analysed stored bufalo (n=29) and cattle (n=471) serum samples collected in 2016 using commercially available enzyme-linked immunosorbent assay kits. Antibodies to Neospora caninum, bovine viral diarrhoea virus (BVDV), Leptospira interrogans serovar Hardjo and Brucella abortus were detected in bufalo samples at 79.3% (95% CI 64.6–94.0), 3.4% (95% CI 0–10.0), 0% and 0%, respectively, and in cattle at 4.2% (95% CI 2.4–6.0), 6.4% (95% CI 4.2–8.6), 8.1% (95% CI 5.6–10.6) and 0%, respectively. The high N. caninum seroprevalence in bufalo was associated with increasing age, with bufalo having a 13.1% chance of being seropositive at birth, increasing to 99.4% by age 7 (p=0.045). This suggests a predominance of horizontal transmission, possibly from exposure to faeces from free-roaming village dogs. Cattle L. interrogans serovar Hardjo seroprevalence was highest in Tbong Khmum province (20.4%) compared to other provinces (p<0.001), and may be compromising bovine fertility and creating a zoonotic risk for smallholders who may contract leptospirosis from farm work. These high infection rates prompt further research to determine: to what extent these pathogens are linked to the low reproductive efciency observed in large ruminants in Cambodia, the risk factors to pathogen exposure and appropriate strategies to reduce these risks. Low BVDV and B. abortus exposure is an important observation. Increasing large ruminant livestock trade into the country will require improved biosecurity and disease surveillance to prevent their emergence. An enhanced understanding of the status of infectious reproductive livestock pathogens in Cambodia can assist development projects to make evidence-based strategies to enhance cattle and bufalo health and improve food security.

Southern corn leaf blight (SCLB), caused by Bipolaris maydis, is one of the most devastating diseases affecting maize production. However, only one SLCB resistance gene, conferring partial resistance, is currently known, underscoring the importance of isolating new SCLB resistance-related genes. Here, we performed a comparative proteomic analysis and identified 258 proteins showing differential abundance during the maize response to B. maydis. These proteins included an ascorbate peroxidase (Zea mays ascorbate peroxidase 1 (ZmAPX1)) encoded by a gene located within the mapping interval of a previously identified quantitative trait locus associated with SCLB resistance. ZmAPX1 overexpression resulted in lower H2O2 accumulation and enhanced resistance against B. maydis. Jasmonic acid (JA) contents and transcript levels for JA biosynthesis and responsive genes increased in ZmAPX1-overexpressing plants infected with B. maydis, whereas Zmapx1 mutants showed the opposite effects. We further determined that low levels of H2O2 are accompanied by an accumulation of JA that enhances SCLB resistance. These results demonstrate that ZmAPX1 positively regulates SCLB resistance by decreasing H2O2 accumulation and activating the JA-mediated defense signaling pathway. This study identified ZmAPX1 as a potentially useful gene for increasing SCLB resistance. Furthermore, the generated data may be relevant for clarifying the functions of plant APXs.

Imidazothiazoles and benzimidazole are the only classes of anthelmintic drugs that have been used over the past 40 years in Fiji. Recently, concerns have arisen that anthelminthic resistance could be widespread and affect animal health and productivity in Fiji. The present study was designed to evaluate the current anthelmintic resistance status in Fiji’s small ruminant farms. The study included 11 farms from the two (Western and Northern divisions) most relevant areas of small ruminant production in Fiji. The anthelmintic treatments tested were levamisole (LEV), albendazole (ALB), levamisole + albendazole combination (LEV+ALB), ivermectin (IVM), moxidectin (MOX), closantel (CLO) and a negative control (CON). The anthelmintic’s efficacy was tested using faecal egg count reduction (FECR) tests and copro-cultures on days 14, 28, and 42 after treatment administration. The lowest mean FECR on day 14 was observed for ALB (65.2 %) followed by LEV (91.6 %), ALB + LEV (94.3 %), IVM (97.4 %) and MOX (98.8 %). The most relevant genera of GIN encountered were Haemonchus and Tri chostrongylus spp., with no distinct pattern of resistance to drug groups between the two populations. None of the tested drugs (MOX and CLO) presented FECR over 95 % on days 28 and 42. Overall, the level of anthelmintic resistance observed was lower than hypothesised for this study. The combination of LEV+ALB has proven effective and presents an appealing treatment option for managing anthelmintic resistance and worm burden reduction in Fiji.

This study assessed the precision and accuracy in the prediction of chemical intramuscular fat (IMF%), Meat Standards Australia (MSA) marbling score and AUS-MEAT eye-muscle area (EMA) using Meat Imaging Japan (MIJ) prototype camera systems. Eleven carcass datasets from the Beef Information Nucleus (BIN) project were compiled with carcass grading, IMF% and camera data. Camera prediction of IMF%, MSA marbling score and EMA was assessed using a leave-one-out cross validation method. There was an association between MIJ mirror and MIJ-30 camera traits and IMF%, MSA marbling score and EMA. However, for both prototypes precision varied for IMF% (R² = 0.4–0.5, RMSECV = 1.5–1.6%), MSA marbling (R² = 0.3–0.5, RMSECV = 57.5–59.3) and EMA (R² = 0.7–0.6, RMSECV = 4.1–5.8 cm² ). Accuracy also fluctuated with average bias values of 1.7–1.8%, 45.8–40.0 units and 3.8–4.1 cm² for IMF%, MSA marbling score and EMA respectively. Key differences between carcass and camera traits and processing factors affecting the grading site are likely to have contributed to this variation.

Immune competence in domestic sheep is gaining more attention in genetic selection programs that seek to enhance flock immunity and animal welfare. A goal of many programs is to identify behavioral phenotypes that indicate stress-coping strength, as well as disease resilience. The current study set out to explore the relationship between immune responsiveness, physiological stress, and behavioral response among sheep that had been selected for 'low' (LR) or 'high' (HR) response to cell-mediated and antibody-mediate reactivity to a clostridial vaccine. Multiparous ewes were placed in four experiments which exposed the animals to various threats including, dog presence, human proximity, visual isolation from flock, and physical restraint. To evaluate the consistency of behavioral phenotypes, all ewes were placed in the test circuit one year later. Basal body temperature (via iButton) and serum cortisol concentrations were collected prior to and after the circuit each year. Immune group (HR vs. LR) was not found to be related to behavioral performance during the dog, human, isolation, or restraint challenge. Immune group categorization was also unrelated to pre- and post-cortisol concentrations, and the change in cortisol concentrations during testing. There was a negative relationship identified between response to visual isolation and change in cortisol response during testing, indicating that sheep which were more active or agitated during visual isolation from the flock experienced less of an increase in serum cortisol levels and were perhaps experiencing a negative, high arousal state compared to less reactive sheep (e.g., freeze behavior) (χ2(4, N=99) = 42.72, P <0.0001). There was also a post hoc, positive relationship identified between weight measurements and immune group, such that individuals with greater body weight were more likely to be in the high immune responsiveness group (P= 0.01). Specifically, for every unit increase in weight, there was a ~49% chance of being categorized in the HR group. This is relevant for selection programs because producers that seek to enhance immune responsiveness and performance may be able to select sheep that carry a greater body mass, and while not found in the present study, could lead to greater flock immunity.

Meat Standards Australia (MSA) sensory protocols have been effectively utilized in beef for international consumers employing several cooking methods. Our objective was to compare the consumer response of Australian and American consumers to paired beef brisket samples utilizing a newly developed low and slow cooking method. Briskets were collected from Australian carcasses with diverse eating quality. Half of the briskets (n = 24) were retained in Australia and their pair was exported to Texas for consumer sensory testing. Naïve consumers (Australia; n = 240) and familiar consumers (USA; n = 240) evaluated paired barbequed briskets for tenderness, juiciness, flavor liking, and overall liking from 0 to 100 using a visual analogue scale, and a weighted composite meat quality score was later calculated. Australian consumers scored briskets lower for tenderness (−4.84 ± 1.70 points) and juiciness (−4.44 ± 1.55 points) and higher for flavor liking (3.48 ± 1.58 points); however, there was no difference between the countries for overall liking (p = 0.75) and combined meat quality score (p = 0.88). Differences between Australian and US consumers’ evaluations indicate that there is an impact of cultural background, potentially driven by Australia’s naivety to the low and slow barbeque cooking method.

Ambient temperature increases occurring under climate change could induce livestock heat stress, resulting in lambing losses and an estimated economic burden of up to Australian $166 million per annum to the Australian sheep industry.

The issue of sheep welfare during live exports has triggered a lot of public concern recently. Extensive research is being carried out to monitor and improve animal welfare. Stocking density can be a critical factor affecting sheep welfare during export and its impact can be monitored through sheep behaviour, position, group dynamics and physiology. In this paper we demonstrate the application of the instance segmentation method Mask R-CNN to support sheep behaviour recognition. As an initial step, two typical behaviours standing and lying are recognized under different group sizes in pens over time. 94%+ mAP was achieved in the validation set demonstrating the effectiveness of the method on identifying sheep behaviours. Further data analysis will provide available space requirements for additional sheep allocation and daily behaviour monitoring to detect abnormal cases which will aim to improve the health and wellbeing of sheep on ships.

A survey of industry groups including nutritionists, producers, feed manufacturers, and technical personnel in broiler and layer operations within the Australian poultry industry was completed to determine the industry’s present views of max-profit and stochastic feed formulation and the barriers they see to implementing these techniques. A total of 32 responses were collected, made up of 17 nutritionists, 4 feed manufacturers, 5 producers, and 6 technical personnel. The survey revealed interest and need to implement stochastic and max-profit feed formulation techniques and identified the key barriers to the implementation of these feed formulation techniques. Barriers identified included limited software to assist nutritionists in using these feed formulation techniques, less data collection than in other animal industries, insufficient training, and possible restrictions on nutritionists via KPIs to minimise diet cost. It was identified that layer farms did not routinely use near-infrared spectroscopy (NIRS) to estimate the nutrient content of feed ingredients and so mostly relied on book values and historical data. Thus, stochastic feed formulation may be particularly useful to buffer the uncertainty and ensure the minimum nutrient requirements of flocks are met. Recommendations were drawn to improve the adoption of max-profit and stochastic feed formulations of Australian layer diets.

Context. In Lao People's Democratic Republic (Laos), goat numbers are rapidly growing and have the potential to improve rural and economic development through income generation. Aims. To implement a goat research and development program and benchmark and evaluate smallholder practices. Methods. In the first year (2020), forage growing was facilitated through formal and on-the-job monthly training. In Year 2 (2021), local staff were trained in inexpensive and locally available veterinary treatments of goats. Mineral blocks were introduced with a 50% subsidy, following a 2-month trial period. In Year 3 (2022), metal roofing material was provided to households that constructed new goat houses with elevated and slatted flooring. Annualised farmer benchmarking surveys (BMS) and monthly household surveys (MHS) monitored farmer practice change between 2020–2023 and 2021–2022 respectively. Key results. The BMS and the MHS confirmed significant rises in the proportion of farmers using mineral blocks between 2020 and 2023 at 303% (P < 0.001) and between 2021 and 2022 at 53% respectively. The BMS and MHS also reflected an increase in the proportion of farmers growing forages between 2020 and 2023 (204%) and between 2021 and 2022 (9%), a decrease in the proportion of households treating sick goats with drugs between 2020 and 2023 (47%) and between 2021 and 2022 (53%), and an increase in the proportion of farmers providing concentrate feed between 2020 and 2023 (34%) and between 2021 and 2022 (increased from 0 to 4.2%) respectively. Conclusions. Mineral blocks have a high potential for adoption with a trial and subsidisation period. It is recommended to increase daily grazing duration from 6–8 h to be as long as practical to reduce the impacts of late dry-season feed shortages (April–May), which coincided with a natural peak in kidding. Average goat herd size increased by three goats over the course of the project, which may reflect improved financial security as livestock are a form of asset storage. Implications. These trends show short-term practice change; however, further research is needed to verify whether these changes increase goat growth rate, health and kid survival.