Context: There are still comparatively few methods for the detection of drug residues in buffalo milk.Aims: This study aims to develop a method for the detection of drug residues in buffalo milk.Methods: In this study, we developed an analytical method for veterinary drug residues in buffalo milk using liquid chromatography–tandem mass spectrometry. The multi-residue method was established for the simultaneous identification and quantitation of eight common veterinary drugs, including metronidazole, salbutamol, atropine, trimethoprim, hydrocortisone, kitasamycin, roxithromycin and tylosin.Key results: The sample processing method for buffalo milk was compared and optimised. The precision, recovery and matrix effects of the method were validated. The precision and accuracy of all analytes ranged from 1.81% to 12.35% and 1.25% to 14.57%, respectively. The average recovery percentages varied between 93.59% and 114.57%, and the average matrix effect ranged from 87.12% to 103.76%. All eight analytes in buffalo milk exhibited stability under different treatment conditions.Conclusions: The developed method was successfully applied to laboratory analysis and routine sample analysis. The method was demonstrated to be rapid, sensitive and reliable for the rapid monitoring of veterinary drug residues in buffalo milk.Implications: The findings of this study contribute to the risk assessment of veterinary drug residues for preventing the human consumption of contaminated buffalo milk and its derivatives.

Context: Reducing livestock emissions, the largest single contributor to agricultural emissions, is increasingly recognised as a high priority. The low biological efficiency of beef cattle, due to their long gestation period, long generational interval, and propensity to be uniparous, contributes to the high methane emissions intensity (kg CO2-e/kg product) of beef compared to most other food products.Aims: We evaluate the potential of increasing the frequency of multiparous births (twinning) as a pathway to reducing the methane intensity of beef and the net methane emissions of intensive beef systems.Methods: We simulate a uniparous herd structure and emissions profile using GrassGro™ livestock systems modelling software and then calculate the effects of an increasing frequency of multiparous births (twinning), up to 1.53 calves per cow joined, on methane emissions.Key results: Our results demonstrate that beef from calves reared as twins has a 22% lower methane intensity than beef from a single reared calf. Although twinning reduces the methane intensity of beef, at the herd level, net methane emissions could rise by as much as 23% at 1.53 calves per cow joined if overall herd size is allowed to grow through an increased number of calves. If we decrease stocking rates, whilst also increasing twinning rates, it is possible to reduce net emissions by up to 14%, without changing productivity.Conclusions: Our results illustrate the significant potential of twinning to decrease the methane intensity of beef and to increase the productivity per cow in intensive beef systems.Implications: Despite this, twinning is unlikely to be a viable net emissions reduction pathway – as twinning will increase stocking rate unless herd structure is altered – unless a commercial or policy driver to reduce net methane emissions is established.

Context: Birth weight can be an important trait in beef cattle through its association with dystocia and increased likelihood of calf and cow mortality. Recording large numbers of birth weights in beef cattle to obtain a suitable genetic evaluation has often been hard to achieve.Aims: We assess if coronet circumference measurements taken at birth and weights and coronet circumference measured post-birth are suitable predictors of birth weight for use in genetic evaluation in northern Australian tropically adapted beef breeds.Methods: Animals were recorded at birth for weight (N = 5352) and coronet circumference (N = 2552), at 3 months of age for the liveweight (N = 2848) and coronet circumference (N = 2855) and liveweight at 6 months (N = 4929). Data were from three tropically adapted beef cattle breeds (viz. Brahman, Droughtmaster and Santa Gertrudis) recorded in two northern Australia herds. Genetic parameters were estimated from a pooled dataset containing all three breeds.Results: Birth weight had an estimated direct and maternal heritability of 0.51 (0.04) and 0.14 (0.02) respectively. Coronet circumference also had high heritabilities, with estimates at birth and 3 months of 0.50 (0.07) and 0.55 (0.06) respectively. The estimated genetic correlation between birth weight and coronet circumference measured at birth was 0.86 (0.03). Birth weight genetic correlations were 0.75 (0.05) with 3-month weight, 0.69 (0.05) with weaning weight and 0.62 (0.05) with coronet circumference at 3 months.Conclusions: Coronet measurements could be used in genetic evaluation as a proxy for birth weight. However, the most useful coronet measure was when it was recorded at birth. This would still require catching the calf at birth, thus greatly reducing the benefit of having an alternative measure. Coronet circumference recorded in the branding cradle at 3 months of age was also a useful predictor of birth weight but added little if post-birth weights were available. Importantly, all post-birth indirect measures of birth weight require adjustment for animal age and, therefore, would need recording of the individual calf’s date of birth.Implications: Coronet circumference recorded at birth and 3 months of age does not appear to be a suitable proxy for genetic evaluation of birth weight.

Context: Climate and economic changes promote the encroachment of woody plants on marginal mountain pastures. In the Alps, the main woody invader is the nitrogen-fixing shrub Alnus viridis (green alder). Robust breeds of different ruminant species may perform well on these shrub-encroached pastures.Aims: To assess the effects of A. viridis encroachment levels of mountain pastures on the growth performance and carcass and meat characteristics of cattle and sheep.Methods: For 8–9 weeks, 22 15-month-old growing Dexter cattle and 20 7-month-old weaned Engadine sheep were grazed rotationally on pastures in a subalpine zone with four different levels of A. viridis encroachment (average: 0.8%, 28.7%, 50.3% and 67.8%). Following slaughter, the assessed carcass and meat characteristics (longissimus thoracis and biceps femoris) included physicochemical meat quality, muscle fibre typing, fatty acid profiling (intramuscular and perirenal fat) and the sensory properties of patties.Key results: The shrub encroachment levels had only minor effects on the animals. Interactions with the animal species influenced some sensory and fatty acid characteristics. The average daily gains were 201 g in the Dexter cattle and 104 g in the Engadine sheep. Both species achieved satisfactory carcass and meat quality and favourably low n-6/n-3 fatty acid ratios (0.63 and 0.68 in the intramuscular fat of the cattle and sheep, respectively). The meat from the Dexter cattle had a slightly higher cooking loss and shear force and a slightly lower proportion of fatty acids relevant to human health. Flavour appreciation was in favour of the burgers prepared from the beef.Conclusions: Both robust breeds were suitable for producing meat on extensive pastures with A. viridis encroachment of up to 70%. Based on indirect evidence, it seems that neither species consumed significant quantities of leaves or bark from the trees.Implications: Our study provides detailed information on rare robust breeds of two animal species in the context of meat production according to customer preferences. To better explain the differences between the two animal species, particularly in terms of fatty acid profiles, the role of the A. viridis understory needs to be clarified.

Context: Soil acidity constrains pasture productivity, limiting production from grazing animals. Lime application can ameliorate acidity, although the rate is increased when incorporated rather than surface applied. Soils in south-eastern Australia are generally highly erodible, containing valuable native grasses that might be lost if disturbed. Surface application is, therefore, the only option, but the extent to which lime can ameliorate acidity and increase pasture and animal production requires research.Aim: This 10-year experiment studied three rates of surface-applied lime, two of superphosphate (P) and two stocking rates (SR) on continuously grazed sheep on acidic soils. Two flocks were studied, one from May 1999 to December 2002, and the second from August 2005 to July 2008. We hypothesised that wool production and animal liveweight would increase as (1) lime rate increased, (2) P rate increased, and (3) peak animal productivity would occur under the combination of the highest rates of lime and P.Key results: The experiment coincided with the Millennium Drought reducing forage production, and slowing lime movement into the soil and consequent amelioration. During Flock 1, effective SR (dry sheep equivalents (DSE)/ha) of the low P, low SR and limed treatment became higher by 1 DSE/ha for 10 months during the final flock measurement months, as drought intensified. During Flock 2, effective SR of both high P, high SR and limed treatments were greater by 2 DSE/ha than non-limed counterpart for the first 9 months of 2006. Trends of higher animal production under lime became clearer with time, so were more apparent in Flock 2 than Flock 1, and at higher SR. High lime, high P and high SR had the greatest wool production. High P, low SR and nil lime was initially highly productive, but declined sharply when legumes disappeared, associated with soil aluminium toxicity. Lime maintained superior ground cover under drought, reducing the danger of sward death and soil erosion, demonstrating its sward preservation, sustainability and ecosystem service benefits.Implications: With the ever-increasing price of land, farmers must increase their land’s productivity. This trial demonstrated production and environmental benefits associated with acid soil amelioration through lime application.

Context: L-citrulline (L-Cit) does not degrade in the rumen and has the ability to form peptide bonds in the body; however, it does not participate in protein synthesis.Aims: This study aimed to evaluate the effects of L-Cit on the reproductive performance of Hu ewes.Methods: In total, 30 ewes were randomly categorised into five groups. The control group was fed with a basic diet, whereas the Experimental Groups I, II, III, and IV were provided feed supplemented with 5, 10, 15, and 20 g/day of L-Cit respectively. Blood samples of ewes were collected 4 h after feeding on Day 21 of the experiment and before feeding on Day 30. The optimal supplementary feeding dose was selected on the basis of blood biochemical indexes. Overall, ninety 2-year-old ewes were classified into two groups. The control group was fed with a basic diet and the experimental group was fed with a diet supplemented with 10 g/day of L-Cit. After 30 days of supplementary feeding, reproductive performance of ewes was determined.Key results: The plasma concentrations of Cit, ornithine, and arginine in ewes increased linearly with an increase in the level of L-Cit supplementation. The plasma concentrations of gonadotropin-releasing hormone, luteinising hormone, and follicle-stimulating hormone in the experimental group increased significantly compared with those in the control group. The plasma total antioxidant capacity and catalase, superoxide dismutase, and glutathione peroxidase in the experimental group were significantly higher than those in the control group, whereas the concentrations of malondialdehyde in all experimental groups were significantly lower than those in the control group. The conception, lambing, and double lambing rates of the experimental group were increased by 28.76%, 15.90%, and 40.21% respectively.Conclusions: Supplementation with different doses of L-Cit can improve the concentrations of some plasma amino acids and reproductive hormones as well as antioxidant capacity of ewes. Supplementary feeding with 10 g/day of L-Cit could increase the lambing and double lambing rates of ewes.Implication: L-Cit can improve the reproductive performance of ewes.

Biological rhythms are repeating patterns that are driven by time-keeping mechanisms within the animal and are adaptive as they coordinate physiology and metabolism with the external environment. The dairy cow has a well recognised natural daily pattern of feed intake and milk synthesis, but regulation of these rhythms has not been well described in the literature or well considered in current dairy management. Recent discoveries have clearly described circadian time-keeping mechanisms in peripheral tissues that are responsive to the timing of food availability. Some management strategies on dairy farms may desynchronise the interactions between central and mammary circadian timekeepers, resulting in reduced milk yield and efficiency. Feeding a total mixed ration is commonly assumed to create constant ruminal conditions, but the large variation in the rate of feed intake across the day causes large fluctuations in rumen fermentation and absorbed nutrients. Milk composition also differs across the day due to both dynamics in nutrient absorption and biological regulation attempting to match milk yield and composition with calf requirements across the day. Recent work has shown that milk synthesis varies over the day and is modified by the timing of feed intake and nutrient absorption. These rhythms have also been shown to be affected by the timing of feed delivery. We expect that maximal milk yield and efficiency are achieved when we have more consistent rumen fermentation and match the timing of nutrient absorption and mammary capacity for milk synthesis. Managing feeding times provides the opportunity to modify feed intake across the day, but behavioural responses are complex. Appreciating the impact of circadian rhythms provides the foundation to develop nutrition and management strategies considering circadian dynamics of intake and milk synthesis and provides opportunities for new gains in cow efficiency, welfare, and health.

Context: Deworming all horses with commercial anthelmintics on a rotational basis every 90 days is still popular worldwide.Aims: To investigate anthelmintic resistance and therapeutic requirements of adult horses on the basis of faecal examinations after a rotation between commercial anthelmintics commonly used in Brazil.Methods: We followed up faecal egg counts and coprocultures of 29 horses for 7 months, after pre-established anthelmintic treatments, every 3 months (August and November 2019 and February 2020). The following commercial anthelmintics were used respectively: moxidectin (1), ivermectin + praziquantel (2) and trichlorfon + mebendazole (3). Faecal egg count (FEC), FEC reduction tests (FECRT) and coproculture were performed before (Day 0) and after 14 days for each of the three treatments. Wilcoxon test (95% confidence level, P 0.05) and mebendazole + trichlorfon (U = 391; P-value >0.05) treatments, there was no difference in FEC between Day 0 and Day 14 at 95% confidence level.Conclusions: The anthelmintics used in the deworming protocol of this study had reduced efficacy against the parasites identified in the coprocultures and the pre-established treatments were probably unnecessary in 93% of the horses with a low level of infection.Implications: This study has highlighted not only the issue of the indiscriminate use of anthelmintics regarding parasitic resistance, but also the exposure of horses to unnecessary treatments. Such widespread use is a costly waste of resources and further reinforces the discontinuation of schedule rather than strategic deworming protocols.

With the increase in worldwide demand for seafood, the current plateau in production from wild-harvest fisheries has resulted in the rapid growth of the aquaculture sector. Aquaculture relies on quality ingredients such as fishmeal, but cost concerns have led to the investigation of a variety of alternate plant and animal by-products and microbial sources as aquafeed ingredients. Evaluation of alternative aquafeed has traditionally focused on their effects on the growth and immune status of the fish and not always on market-driven assessments of the final edible product. One of the commonly researched groups of alternative ingredients is seafood waste, which, after transformation, has potentially beneficial nutritional characteristics. Transformation, which includes rendering, enzyme hydrolysis and use as a feed source for insects and microbial species, is intended to provide stability and enhance the logistical feasibility of the waste as an aquafeed ingredient. This review discusses transformed fish waste in aquafeeds and describes some of the market and end-user implications (composition, edible safety and quality, sustainability metrics and consumer perceptions) of this approach.

The global goat meat sector is advancing and contributes to long-term food security, especially in meeting the protein demands of the growing human population in developing countries. Spanning all countries, Australia, is the largest exporter of goat meat, although it has negligible consumption. However, Australia does potentially have a secure future as an innovative, profitable, and resilient world leader in goat production, provided some challenges are addressed. These challenges facing the goat meat sector require suitable strategies and interventions for better profitability and acceptance of goat meat consumed in Australia and as an export product. Limited research on goat meat quality and the lack of an adequate grading system for goat meat quality are two of the major issues that need attention from the industry and researchers. Some of the most critical areas that need further research to enable growth of the goat meat industry are the influence of genetics and age of animals on meat quality, standardisation of the ageing period of various goat meat cuts, cooking innovations, consumer acceptance and sensory analysis of goat meat (both farmed and rangeland goats). This paper reviews the status of the goat meat sector and identifies the opportunities for the goat meat sector, particularly in Australia. In addition, we highlight several key issues requiring further research and interventions to enhance the growth of the goat meat industry.

Context: Cow survival is an important trait for dairy farm profitability and animal welfare, yet it is difficult to improve because of its complexity arising, in part, from varied reasons for culling and delay in getting actual culling data, which leads to low accuracy and instability of genetic predictions.Aims: To explore the benefits of partitioning the cow survival trait into ‘early survival’ (survival coded as a binary trait from the first to the second lactation) and ‘late survival’ (survival from the second to later lactations) on genetic predictions in addition to predictors of culling decisions.Methods: The raw phenotypic survival records for 1 619 542 Holstein and 331 996 Jersey cows were used in our study. All cows within each herd were allocated to either a reference or validation set. The accuracy and stability of genetic predictions were compared across lactations in the validation set. Further, we estimated the phenotypic and genetic correlation between overall, early or late cow survival and production, type, workability, and fertility traits using bivariate sire models.Key results: The heritability of overall survival in Jerseys (0.069 ± 0.003) was higher than in Holsteins (0.044 ± 0.001). The heritability of early survival was higher than that of late survival in Holstein (0.039 ± 0.002 vs 0.036 ± 0.001) and Jersey (0.080 ± 0.006 vs 0.053 ± 0.003). The genetic correlation between early and late survival was high in both breeds (0.770 ± 0.017 in Holstein and 0.772 ± 0.028 in Jersey). Adding survival information up to the sixth lactation had a large effect on genetic predictions of overall and late survival, whereas the predictions of early survival remained the same across lactations. Milk and protein yields, somatic cell score, fertility and temperament were highly correlated with early survival in Holstein and Jersey. However, the genetic correlations between production, type or workability traits and late survival were generally weaker than those and early survival.Conclusions: Early and late survival should be considered as different traits in genetic evaluations, because they are associated with different culling decisions.Implications: Partitioning cow survival into early and late survival and analysing them as two correlated traits could improve the accuracy and the stability of estimated breeding values compared with analysing overall survival as a single trait.

Context: Red deer farming in New Zealand has increased in intensity, increasing the emissions to water and air. Outdoor wintering systems pose a significant threat to water quality through sediment loss and nitrate leaching. Changing wintering systems to bring animals indoors shifts emphasis to greenhouse-gas emissions.Aims: To investigate the relative potential emissions to water and air when red deer are wintered outdoors on forage crops or indoors on supplements.Methods: The impacts of wintering red deer on forage or indoors were calculated for five farms, involving 32 herds containing 2167 deer over 2 years, in southern New Zealand. Animal classes included weaners, hinds and stags. Potential losses to water included sediment, nitrogen and phosphorous, while losses to air included methane, nitrous oxide and ammonia. Losses to air were calculated using current New Zealand greenhouse-gas inventory calculations and revised calculations recognising published forage, soil and bedding emissions factors not yet included in the inventory.Key results: Calculated outdoor winter feed intake was 9.5% greater than indoor measured feed intake. The average herd size of 115 deer wintered indoors for an average of 87 days would have needed 1.8 ha of winter forage crop. Potential losses of sediment, nitrogen and phosphorus were calculated to be 5362, 106 and 5.2 kg per herd respectively, if wintered on crop. Total greenhouse-gas (GHG) emissions calculated using current inventory emission factors were higher if deer grazed a forage crop than when wintered indoors (2.58 vs 2.41 kg CO2-e/head/day respectively). When revised emission factors were used, indoor wintering produced greater GHG emissions than did wintering outdoors (2.61 vs 2.28 kg CO2-e/head/day respectively).Implications: Variability may occur both in contaminant loss to water and emissions to air. Trade-offs between the two need to be recognised in decision-making. As the science of GHG develops, the relative ranking of different systems may change.

The measurement and prediction of pasture intake in extensive grazing systems, typical of northern Australia, remain elusive after 50 years of research. The aim of this paper is to review research conducted over the past 50 years, highlight advances in understanding, discuss remaining challenges and consider future developments with digital technologies. While the fundamental components of voluntary intake are well understood, their measurement is difficult, particularly in extensive grazing systems, which has limited the development of predictive models that adequately address the interplay of factors influencing intake from the bite to the landscape scale. Ongoing research by the authors is used as an example to highlight the potential application of digital technologies to overcome limitations in measurement and prediction. Digital technologies offer the opportunity for monitoring factors that control voluntary pasture intake at scale and under commercial conditions. However, our ability to ground-truth novel indices of intake remains limited without ongoing development of physical methods. This will limit the accuracy and precision of predictive models incorporating digital technologies that can be applied to the extensive grazing conditions of northern Australia. The advent of precision livestock management for extensive cattle production is essential if the industry is to remain viable in the future where production is transparent, ethically sound and environmentally defensible as well as profitable.

Context: Milk yield and fertility are negatively genetically correlated in dairy cows, so selection for milk yield would be expected to result in genetic deterioration in fertility unless there is concurrent selection for fertility.Aim: The main study aim was to describe temporal trends in estimated breeding values (Australian Breeding Values, ABVs) for daughter fertility for Holstein and Jersey cows in Australian dairy herds.Methods: A retrospective descriptive study was conducted using milk recording and ABV data from cows in commercial dairy herds. Calvings and lactations from 1980 to 2022 were used, along with ABVs for cows that calved over that period and for sires of those cows. Herd-year mean estimated breeding values were calculated for each breed as the means for cows of that breed that calved in the herd that year.Key results: Daughter fertility ABVs declined (i.e. deteriorated) markedly in Holsteins in the Australian dairy industry, commencing before 1980. Rates of decline were most rapid in sires, less rapid in cows and least rapid at herd level. Selection pressure for cows with higher daughter fertility ABVs due to cow culling decisions was probably occurring within Australian herds but any such effect was minimal. The decline in cow daughter fertility ABVs is being reversed, but recovery of herd means in the study population has been slow. The rate of decline in daughter fertility ABVs in Jersey cows was less than for Holsteins.Conclusions: Over a period of genetic deterioration, then recovery for a trait, genetic trends in sires are not closely related to genetic trends at herd level. The rapid decline in daughter fertility ABVs for sires probably resulted in substantial reductions in herd reproductive performance and cow longevity in Holstein herds in the Australian dairy industry. Under current trends, it will be a considerable time before the adverse effects of the decline in daughter fertility ABVs are fully reversed.Implications: An important ongoing task for animal breeding is to identify and monitor traits that may become important for farmers and community in future but may be declining genetically under current selection decisions.

Context: The need for the storage of fertile eggs is a reality in the poultry industry. At the same time, prolonged storage periods decrease the quality of egg components that are essential for embryo development, and can compromise hatchability and chick quality; thus, the high content of unsaturated fatty acids in embryo tissues increase the susceptibility to peroxidation.Aims: The objective of this study was to evaluate the addition of cis-9, trans-11, trans-10 and cis-12 isomers of conjugated linoleic acid (CLA) to the broiler-breeder diet and the storage time on the internal egg quality, composition and lipid oxidation.Methods: In total, 22 000 Cobb female broiler breeders of 58 weeks of age were fed with diets containing 0 or 0.024% CLA and fertile eggs were stored 3, 6 or 9 days prior to incubation. In total, 6912 hatching eggs were used in a completely randomised experimental design in a 2 × 3 factorial arrangement (CLA inclusion × egg storage time). At the end of each storage period, 30 eggs per dietary treatment were sampled to analyse yolk and albumen height, percentage and pH, yolk:albumen ratio, yolk diameter and index, Haugh unit (HU), yolk lipid oxidation, acidity and fatty acid profile.Key results: The progression of storage negatively affected the internal quality of the eggs; however, inclusion of CLA minimised these effects up to Day 6, especially for yolk diameter, HU, height and albumen pH. The total lipid content was not affected by the dietary treatments; however, CLA inclusion resulted in a higher proportion of stearic acid and a lower concentration of linoleic acid in yolks.Conclusions: The changes observed in fatty acid profile of the eggs may have favoured the reduction of lipid oxidation, as shown by the decrease in the acidity index and thiobarbituric acid-reactive substance (TBARS) values at shorter storage periods.Implications: The dietary addition of CLA to broiler breeders may be used to preserve the egg internal quality during a short-term storage period.

Context: A significant opportunity remains to further increase the supply of premium sheepmeat products to Australia’s customers, which requires a more rapid rebuilding of the national sheep flock. To help meet this challenge, developing relevant information for sheep producers to assist them to achieve a profitable flock-rebuilding outcome is viewed as highly desirable.Aims: (1) Develop flock-rebuild scenarios that track inventory, cashflow, profit and loss, and the overall balance sheet over a 5-year projection. (2) Model the impact on flock-rebuilding pathways of exposure to variation in supplementary-feed costs, purchase of stock and price received for sale animals and flock structure. (3) Model variation in benefits and costs for a range of production zones, enterprise types and flock-age profiles.Methods: Fourteen flock-rebuilding pathways were assessed for up to nine flock types, using a spreadsheet model that tracked inventory, cashflow, profit and loss, and the overall balance sheet over 5 years.Key results: The top four pathways for profitability and capacity to rapidly rebuild flock numbers include retention of more older ewes, purchasing young ewes, purchasing older ewes (mostly 5–6-year olds) in Merino and Merino-cross flock types only and joining ewe lambs in Maternal and Cleanskin flock types only. These pathways were not sensitive to variation in the cost of supplementary feed, stock prices or flock structure, although joining Merino ewe lambs became one of the top four pathways when feed costs were lower.Conclusions and implications: The well established practices of retaining ewes for longer and purchasing ewes, especially young ewes, have the most potential to both rapidly and profitably rebuild flock numbers. However, joining ewe lambs, particularly in Maternal and Cleanskin flocks, can also profitably contribute to rapid flock rebuilding. While reducing reproductive wastage or increasing reproductive potential were mostly profitable, they could not rapidly rebuild flock numbers. In contrast, accelerated lambing systems can rapidly rebuild flock numbers, but are only marginally profitable.

Context: The Patagonian huemul, an endangered Odocoilinedeer, has an estimated 350–500 individuals remaining in Argentina. Today’s population size, representing a numerical reduction of >99% of original estimates, is fragmented into small groups along ~2000 km of Andean mountains. The species’ numbers were heavily reduced by past overexploitation and they disappeared in areas of high anthropogenic activity, predominantly the fertile valley bottoms.Aims: This research delineates the current potential distribution of Patagonian huemul by using climatic indicators, topographic and vegetational proxies, and anthropogenic pressure, to determine the relevance of the climatic envelope on current distribution.Methods: Occurrence records (latitude and longitude) were compiled (n = 159) by consulting the literature. Twenty environmental variables were used (WorldClim database) and two other representative environmental variables (normalised difference vegetation index (NDVI) and enhanced vegetation index (EVI)) were added to test their predictive power. We added the human footprint index (HFP) as a variable to control for model bias. Using the maximum entropy algorithm (MaxEnt), we modelled the species’ potential distribution. We designated the historical distribution as area M. Additionally, we calculated three areas of distribution: current, historical and potential. Finally, we calculated distributional retraction of the species and area lost per year.Key results: The model showed good predictive power (AUCTest = 0.764 ± 0.091). However, low values were obtained for AUCtrain and AUCprom for the different predictor scenarios. Although the model shows the interaction among several climatic, environmental, and topographic variables, the human footprint index (39.9%) was the variable that most influenced the current potential distribution of this species.Conclusion: Our model shows that most of Patagonia’s surface is climatically suitable for huemul. This suggests that the causes of distributional retraction are not related to limitations imposed by the climate envelope, but rather concur with recent research showing impact owing to the species’ behavioural response to anthropogenic activity.Implications: Current populations are small, fragmented, and confined to poor-quality sites. Although the species is currently found mainly within protected areas, management actions must be initiated that promote innovative strategies in unprotected areas, as well as high-value habitats, particularly as protected areas contain limited fertile lower-valley habitats.

Context: Utilising crop residues is an effective strategy to compensate for the shortage of common feed resources. Different processing methods can improve the nutritional value of these by-products.Aims: This study aimed to investigate the effect of sodium hydroxide (NaOH, 50 g/kg dry matter (DM)), calcium oxide (CaO, 160 g/kg DM), hydrobromic acid (HBr, 60 mL/kg DM), and hydrogen peroxide (H2O2, 57 mL/kg DM) processing on the nutritional value of common bean (Phaseolus vulgaris) residues (CBR).Methods: The chemical composition of the samples was determined using standard methods. In addition, a degradability trial was conducted using the nylon-bag technique. Furthermore, in vitro digestibility of the samples was determined by the batch-culture method. Moreover, the X-ray powder diffraction technique was used to calculate the crystallinity degree of the samples.Key results: Chemical processing was effective on the chemical composition of the residues (P < 0.05). Treatments of CaO, H2O2, and NaOH increased the ash content. Chemicals reduced the neutral detergent fibre and acid detergent fibre. Other treatments, excluding CaO, increased total digestible nutrients, net energy for lactation, and net energy for gain. NaOH, H2O2 and HBr treatments increased the effective ruminal degradability of DM at ruminal outflow rates of 0.02, 0.05, and 0.08/h (P < 0.0001). Chemical processing caused a decrease in gas production (GP) and estimated parameters of CBR (P < 0.0001). The decrease in GP, short-chain fatty acids, metabolisable energy, and organic-matter digestibility in the NaOH and CaO treatments was more than in HBr and H2O2 treatments. After 24 h of incubation, all treatments except CaO increased the partitioning factor and decreased the gas yield (P < 0.0001). Furthermore, processing with NaOH and H2O2 increased the microbial biomass (P = 0.0128) and its efficiency (P < 0.0001) at the end of a 24 h incubation period. Moreover, different treatments reduced the crystallinity degree of CBR compared with the control. Notably, the lowest crystallinity percentage was observed in HBr-treated samples.Conclusions: This study shows that chemical treatments (except for CaO) improve CBR nutritional value under in vitro and in situ conditions.Implications: In vivo tests are required to validate the results.

This review considers the potential role of multispecies swards in de-risking Australian dairy systems that currently rely heavily on monocultures of perennial ryegrass and high rates of inorganic nitrogen application to be productive. Recent trends in increasing inorganic nitrogen fertiliser prices, societal pressure for increased environmental sustainability of farming practices, coupled with variable and extreme weather events have renewed interest for functionally diverse pasture mixtures. Evidence from the latest international studies either for or against the purported benefits of multispecies swards (e.g. productive, resilient, and environmentally positive) is examined. There is an ever-growing body of evidence confirming that species richness can promote high levels of productivity at low or zero rates of nitrogen fertiliser application, often with increasingly positive effects as species richness increases. However, results within and between different levels of species richness are not always consistent, suggesting that not all multispecies swards will perform alike, even at a constant level of functional diversity. A multitude of other factors is presented that interact to determine the success of one multispecies sward over another. These include soil type and fertility, species choice, functional group proportions, sward management under either grazing or cutting, fertiliser regimes, and grazing management practices. It was concluded that this complexity gives rise to a need for further research into the biological mechanisms behind multispecies mixtures to determine the factors, other than simply species richness, that will guarantee success as more farmers inevitably search for alternatives to perennial ryegrass pasture in the Australian dairy farming industry.

Context: Mycoplasma hyopneumoniae causes enzootic pneumonia, predisposing pigs to infections with other respiratory pathogens. The main control measure is to reduce piglet exposure at lactation, which can be achieved by gilts’ acclimation prior to their entrance to the farms. One of the acclimation strategies is aerosol exposure with a positive inoculum by using a fogger. However, studies on its efficacy in gilts and their litters are lacking in the literature.Aim: The aim of this case study was to assess the efficacy fogging with a positive inoculum of M. hyopneumoniae to expose negative gilts in an acclimation program. Moreover, the infection dynamics of M. hyopneumoniae were assessed in their piglets from lactation to slaughter.Methods: The trial was performed in two phases. In Phase 1, a total of 34 and 107 gilts was selected from Farms A and B respectively, and then exposed to the inoculum through a fogger. In Phase 2, a subsample of 74 gilts from Farm B was followed to their first farrowing and 263 piglets born to those gilts were sampled from 15 to 170 days of age, and at slaughter, lung lesions were evaluated.Key results: In Phase 1, the prevalence of positive gilts at 28 days post-exposure (dpe) was 100% and 98.1% in Farms A and B respectively. In Phase 2, 10.8% of gilts remained positive at 180 dpe and 0.8% of piglets were positive at 15 days of age (day) and 28.1% at 60 days, suggesting a possible vertical transmission.Conclusion: The use of fogging with a lung homogenate positive for M. hyopneumoniae successfully acclimated negative gilts. However, it did not avoid the presence of positive gilts at farrowing and the detection of the bacterium in their progeny by polymerase chain reaction.Implications: The exposure of gilts to M. hyopneumoniae at 150 days of age was successfully achieved by fogging. However, consideration should be given to exposing replacement gilts of a younger age in order to reduce the odds of detecting positive gilts at first farrowing.