For livestock production systems to play a positive role in global food security, the balance between their benefits and disbenefits to society must be appropriately managed. Based on the evidence provided by field-scale randomised controlled trials around the world, this debate has traditionally centred on the concept of economic-environmental trade-offs, of which existence is theoretically assured when resource allocation is perfect on the farm. Recent research conducted on commercial farms indicates, however, that the economic-environmental nexus is not nearly as straightforward in the real world, with environmental performances of enterprises often positively correlated with their economic profitability. Using high-resolution primary data from the North Wyke Farm Platform, an intensively instrumented farm-scale ruminant research facility located in southwest United Kingdom, this paper proposes a novel, information-driven approach to carry out comprehensive assessments of economic-environmental trade-offs inherent within pasture-based cattle and sheep production systems. The results of a data-mining exercise suggest that a potentially systematic interaction exists between ‘soil health’, ecological surroundings and livestock grazing, whereby a higher level of soil organic carbon (SOC) stock is associated with a better animal performance and less nutrient losses into watercourses, and a higher stocking density with greater botanical diversity and elevated SOC. We contend that a combination of farming system-wide trials and environmental instrumentation provides an ideal setting for enrolling scientifically sound and biologically informative metrics for agricultural sustainability, through which agricultural producers could obtain guidance to manage soils, water, pasture and livestock in an economically and environmentally acceptable manner. Priority areas for future farm-scale research to ensure long-term sustainability are also discussed.

Up to the 18th century, the prevailing view of reproduction, or ‘generation’ as it was referred to, was that organisms develop from miniatures of themselves, termed preformation. The alternative theory, epigenesis, proposed that the structure of an animal emerges gradually from a relatively formless egg. The teachings of the Ancient Greeks who argued either that both sexes each contributed ‘semen’ to form the embryo, or held a more male-centred view that the female merely provided fertile ground for the male seed to grow, dominated thinking until the 17th century, when the combined work of numerous scholars led to the theory that all female organisms, including humans, produced eggs. The sequence of events leading to the commercial use of artificial insemination (AI) date back to the discovery of sperm in 1678, although it took almost 100 years to demonstrate that sperm were the agents of fertilisation and a further 100 years for the detailed events associated with fertilisation to be elucidated. The first successful AI, carried out in the dog, dates back to 1780 while it was not until the early to mid-1900s that practical methods for AI were described in Russia. Inspired by the Russian success, the first AI cooperative was established in Denmark in 1936 and later in the United States in 1938. The next major advances involved development of semen extenders, addition of antibiotics to semen, and the discovery in 1949 that glycerol protected sperm during cryopreservation. Almost four decades later, the flow cytometric separation of X- and Y-bearing sperm opened a new chapter in the application of AI for cattle breeding. As we look forward today, developments in imaging sperm and breakthroughs in gene editing and stem cell technology are opening up new possibilities to manipulate reproduction in a way never thought possible by the pioneers of the past. This review highlights some of the main milestones and individuals in the history of sperm biology and the development of technologies associated with AI in cattle.

Curcumin has been attributed with antioxidant, anti-inflammatory, antibacterial activities, and has shown highly protective effects against enteropathogenic bacteria and mycotoxins. Ochratoxin A (OTA) is one of the major intestinal pathogenic mycotoxins. The possible effect of curcumin on the alleviation of enterotoxicity induced by OTA is unknown. The effects of dietary curcumin supplementation on OTA-induced oxidative stress, intestinal barrier and mitochondrial dysfunctions were examined in young ducks. A total of 540 mixed-sex 1-day-old White Pekin ducklings with initial BW (43.4±0.1 g) were randomly assigned into controls (fed only the basal diet), a group fed an OTA-contaminated diet (2 mg/kg feed), and a group fed the same OTA-contaminated feed plus 400 mg/kg of curcumin. Each treatment consisted of six replicates, each containing 30 ducklings and treatment lasted for 21 days. There was a significant decrease in average daily gain (ADG) and increased feed : gain caused by OTA (P<0.05); curcumin co-treatment prevented the decrease in BW and ADG compared with the OTA group (P<0.05). Histopathological and ultrastructural examination showed clear signs of enterotoxicity caused by OTA, but these changes were largely prevented by curcumin supplementation. Curcumin decreased the concentrations of interleukin-1β, tumor necrosis factor-α and malondialdehyde, and increased the activity of glutathione peroxidase induced by OTA in the jejunal mucosa of ducks (P<0.05). Additionally, curcumin increased jejunal mucosa occludin and tight junction protein 1 mRNA and protein levels, and decreased those of ρ-associated protein kinase 1 (P<0.05). Notably, curcumin inhibited the increased expression of apoptosis-related genes, and downregulated mitochondrial transcription factors A, B1 and B2 caused by OTA without any effects on RNA polymerase mitochondrial (P<0.05). These results indicated that curcumin could protect ducks from OTA-induced impairment of intestinal barrier function and mitochondrial integrity.

Methane produced from formate is one of the important methanogensis pathways in the rumen. However, quantitative information of CH4 production from formate has been rarely reported. The aim of this study was to characterize the conversion rate (CR) of formic acid into CH4 and CO2 by rumen microorganisms. Ground lucerne hay was incubated with buffered ruminal fluid for 6, 12, 24 and 48 h. Before the incubation, 13C-labeled H13COOH was also supplied into the incubation bottle at a dose of 0, 1.5, 2.2 or 2.9 mg/g of DM substrate. There were no interactions (P>0.05) between dose and incubation time for all variables evaluated. When expressed as an absolute amount (ml in gas sample) or a relative CR (%), both 13CH4 and 13CO2 production quadratically increased (P<0.01) with the addition of H13COOH. The total 13C (13CH4 and 13CO2) CR was also quadratically increased (P<0.01) when H13COOH was added. Moreover, formate addition linearly decreased (P<0.031) the concentrations of NH3-N, total and individual volatile fatty acids (acetate, propionate and butyrate), and quadratically decreased (P<0.014) the populations of protozoa, total methanogens, Methanosphaera stadtmanae, Methanobrevibacter ruminantium M1, Methanobrevibacter smithii and Methanosarcina barkeri. In summary, formate affects ruminal fermentation and methanogenesis, as well as the rumen microbiome, in particular microorganisms which are directly or indirectly involved in ruminal methanogenesis. This study provides quantitative verification for the rapid dissimilation of formate into CH4 and CO2 by rumen microorganisms.

The use of sexed semen in dairy and beef cattle production provides a number of benefits at both farm and industry levels. There is an increasing demand for dairy and beef products across the globe, which will necessitate a greater focus on improving production efficiency. In dairy farming, there is surplus production of unwanted male calves. Male dairy calves increase the risk of dystocia compared with heifer calves, and as an unwanted by-product of breeding with conventional semen, they have a low economic value. Incorporating sexed semen into the breeding programme can minimise the number of unwanted male dairy calves and reduce dystocia. Sexed semen can be used to generate herd replacements and additional heifers for herd expansion at a faster rate from within the herd, thereby minimising biosecurity risks associated with bringing in animals from different herds. Furthermore, the use of sexed semen can increase herd genetic gain compared with use of non-sorted semen. In dairy herds, a sustainable breeding strategy could combine usage of sexed semen to generate replacements only, and usage of beef semen on all dams that are not suitable for generating replacements. This results in increased genetic gain in dairy herd, increased value of beef output from the dairy herd, and reduced greenhouse gas emissions from beef. It is important to note, however, that even a small decrease in fertility of sexed semen relative to conventional semen can negate much of the economic benefit. A high fertility sexed semen product has the potential to accelerate herd expansion, minimise waste production, improve animal welfare and increase profitability compared with non-sorted conventional semen.

This paper discusses the sustainability of livestock systems, emphasising bidirectional relations with animal health. We review conventional and contrarian thinking on sustainability and argue that in the most common approaches to understanding sustainability, health aspects have been under-examined. Literature review reveals deep concerns over the sustainability of livestock systems; we recognise that interventions are required to shift to more sustainable trajectories, and explore approaches to prioritising in different systems, focusing on interventions that lead to better health. A previously proposed three-tiered categorisation of ‘hot spots’, ‘cold spots’ and ‘worried well’ animal health trajectories provides a mental model that, by taking into consideration the different animal health status, animal health risks, service response needs and key drivers in each system, can help identify and implement interventions. Combining sustainability concepts with animal health trajectories allows for a richer analysis, and we apply this to three case studies drawn from North Africa and the Middle East; Bangladesh; and the Eastern Cape of South Africa. We conclude that the quest for sustainability of livestock production systems from the perspective of human and animal health is elusive and difficult to reconcile with the massive anticipated growth in demand for livestock products, mainly in low- and middle-income countries, as well as the aspirations of poor livestock keepers for better lives. Nevertheless, improving the health of livestock can contribute to health sustainability both through reducing negative health impacts of livestock and increasing efficiency of production. However, the choice of the most appropriate options must be under-pinned by an understanding of agro-ecology, economy and values. We argue that a new pillar of One Health should be added to the three traditional sustainability pillars of economics, society and environment when addressing livestock systems.

Fertility is one of the most economically important traits in both beef and dairy cattle production; however, only female fertility is typically subjected to selection. Male and female fertility have only a small positive genetic correlation which is likely due to the existence of a relatively small number of genetic variants within each breed that cause embryonic and developmental losses. Genomic tools have been developed that allow the identification of lethal recessive loci based upon marker haplotypes. Selection against haplotypes harbouring lethal alleles in conjunction with selection to improve female fertility will result in an improvement in male fertility. Genomic selection has resulted in a two to fourfold increase in the rate of genetic improvement of most dairy traits in US Holstein cattle, including female fertility. Considering the rapidly increasing rate of adoption of high-throughput single nucleotide polymorphism genotyping in both the US dairy and beef industries, genomic selection should be the most effective of all currently available approaches to improve male fertility. However, male fertility phenotypes are not routinely recorded in natural service mating systems and when artificial insemination is used, semen doses may be titrated to lower post-thaw progressively motile sperm numbers for high-merit and high-demand bulls. Standardization of sperm dosages across bull studs for semen distributed from young bulls would allow the capture of sire conception rate phenotypes for young bulls that could be used to generate predictions of genetic merit for male fertility in both males and females. These data would allow genomic selection to be implemented for male fertility in addition to female fertility within the US dairy industry. While the rate of use of artificial insemination is much lower within the US beef industry, the adoption of sexed semen in the dairy industry has allowed dairy herds to select cows from which heifer replacements are produced and cows that are used to produce terminal crossbred bull calves sired by beef breed bulls. Capture of sire conception rate phenotypes in dairy herds utilizing sexed semen will contribute data enabling genomic selection for male fertility in beef cattle breeds. As the commercial sector of the beef industry increasingly adopts fixed-time artificial insemination, sire conception rate phenotypes can be captured to facilitate the development of estimates of genetic merit for male fertility within US beef breeds.

Automatic milking systems (AMS), or milking robots, are becoming widely accepted as a milking technology that reduces labour and increases milk yield. However, reported amount of labour saved, changes in milk yield, and milk quality when transitioning to AMS vary widely. The purpose of this study was to document the impact of adopting AMS on farms with regards to reported changes in milking labour management, milk production, milk quality, and participation in dairy herd improvement (DHI) programmes. A survey was conducted across Canada over the phone, online, and in-person. In total, 530 AMS farms were contacted between May 2014 and the end of June 2015. A total of 217 AMS producers participated in the General Survey (Part 1), resulting in a 41% response rate, and 69 of the respondents completed the more detailed follow-up questions (Part 2). On average, after adopting AMS, the number of employees (full- and part-time non-family labour combined) decreased from 2.5 to 2.0, whereas time devoted to milking-related activities decreased by 62% (from 5.2 to 2.0 h/day). Median milking frequency was 3.0 milkings/day and robots were occupied on average 77% of the day. Producers went to fetch cows a median of 2 times/day, with a median of 3 fetch cows or 4% of the herd per robot/day. Farms had a median of 2.5 failed or incomplete milkings/robot per day. Producers reported an increase in milk yield, but little effect on milk quality. Mean milk yield on AMS farms was 32.6 kg/cow day. Median bulk tank somatic cell count was 180 000 cells/ml. Median milk fat on AMS farms was 4.0% and median milk protein was 3.3%. At the time of the survey, 67% of producers were current participants of a DHI programme. Half of the producers who were not DHI participants had stopped participation after adopting AMS. Overall, this study characterized impacts of adopting AMS and may be a useful guide for making this transition.

The Meat Standards Australia (MSA) grading scheme has the ability to predict beef eating quality for each ‘cut×cooking method combination’ from animal and carcass traits such as sex, age, breed, marbling, hot carcass weight and fatness, ageing time, etc. Following MSA testing protocols, a total of 22 different muscles, cooked by four different cooking methods and to three different degrees of doneness, were tasted by over 19 000 consumers from Northern Ireland, Poland, Ireland, France and Australia. Consumers scored the sensory characteristics (tenderness, flavor liking, juiciness and overall liking) and then allocated samples to one of four quality grades: unsatisfactory, good-every-day, better-than-every-day and premium. We observed that 26% of the beef was unsatisfactory. As previously reported, 68% of samples were allocated to the correct quality grades using the MSA grading scheme. Furthermore, only 7% of the beef unsatisfactory to consumers was misclassified as acceptable. Overall, we concluded that an MSA-like grading scheme could be used to predict beef eating quality and hence underpin commercial brands or labels in a number of European countries, and possibly the whole of Europe. In addition, such an eating quality guarantee system may allow the implementation of an MSA genetic index to improve eating quality through genetics as well as through management. Finally, such an eating quality guarantee system is likely to generate economic benefits to be shared along the beef supply chain from farmers to retailors, as consumers are willing to pay more for a better quality product.

Social and health care provision have led to substantial increases in life expectancy. In the UK this has become higher than 80 years with an even greater proportional increase in those aged 85 years and over. The different life stages give rise to important nutritional challenges and recent reductions in milk consumption have led to sub-optimal intakes of calcium by teenage females in particular when bone growth is at its maximum and of iodine during pregnancy needed to ensure that supply/production of thyroid hormones to the foetus is adequate. Many young and pre-menopausal women have considerably sub-optimal intakes of iron which are likely to be associated with reduced consumption of red meat. A clear concern is the low intakes of calcium especially as a high proportion of the population is of sub-optimal vitamin D status. This may already have had serious consequences in terms of bone development which may not be apparent until later life, particularly in post-menopausal women. This review aims to examine the role of dairy foods and red meat at key life stages in terms of their ability to reduce or increase chronic disease risk. It is clear that milk and dairy foods are key sources of important nutrients such as calcium and iodine and the concentration of some key nutrients, notably iodine can be influenced by the method of primary milk production, in particular, the iodine intake of the dairy cow. Recent meta-analyses show no evidence of increased risk of cardiovascular diseases from high consumption of milk and dairy foods but increasing evidence of a reduction in the risk of type 2 diabetes associated with fermented dairy foods, yoghurt in particular. The recently updated reports from the World Cancer Research Fund International/American Institute for Cancer Research on the associations between dairy foods, red meat and processed meat and various cancers provide further confidence that total dairy products and milk, are associated with a reduced risk of colorectal cancer and high intakes of milk/dairy are not associated with increased risk of breast cancer. Earlier evidence of a significant increase in the risk of colorectal cancer from consumption of red and particularly processed meat has been reinforced by the inclusion of more recent studies. It is essential that nutrition and health-related functionality of foods are included in evaluations of sustainable food production.

In beef cattle, feeding behaviour and activity are associated with feed efficiency and methane (CH4) emissions. This study aimed to understand the underlying traits responsible for the contribution of cattle behaviour to individual differences in feed efficiency, performance and CH4 emissions. A total of 84 steers (530±114 kg BW) of two different breeds (crossbreed Charolais and Luing) were used. The experiment was a 2×2×3 factorial design with breed, basal diets (concentrate v. mixed) and dietary treatments (no additive, calcium nitrate or rapeseed cake) as the main factors. The individual dry matter intake (DMI; kg) was recorded daily and the BW was measured weekly over a 56-day period. Ultrasound fat depth was measured on day 56. Based on the previous data, the indexes average daily gain, food conversion and residual feed intake (RFI) were calculated. The frequency of meals, the duration per visit and the time spent feeding per day were taken as feeding behaviour measures. Daily activity was measured using the number of steps, the number of standing bouts and the time standing per day. Agonistic interactions (including the number of contacts, aggressive interactions, and displacements per day) between steers at the feeders were assessed as indicators of dominance. Temperament was assessed using the crush score test (which measures restlessness when restrained) and the flight speed on release from restraint. Statistical analysis was performed using multivariate regression models. Steers that spent more time eating showed better feed efficiency (P=0.039), which can be due to greater secretion of saliva. Feeding time was longer with the mixed diet (P<0.001), Luings (P=0.009) and dominant steers (P=0.032). Higher activity (more steps) in the pen was associated with poorer RFI, possibly because of higher energy expenditure for muscle activity. Frequent meals contributed to a reduction in CH4 emissions per kg DMI. The meal frequency was higher with a mixed diet (P<0.001) and increased in more temperamental (P=0.003) and dominant (P=0.017) steers. In addition, feed intake was lower (P=0.032) in more temperamental steers. This study reveals that efficiency increases with a longer feeding time and CH4 emissions decrease with more frequent meals. As dominant steers eat more frequently and for longer, a reduction in competition at the feeder would improve both feed efficiency and CH4 emissions. Feed efficiency can also be improved through a reduction in activity. Selection for calmer cattle would reduce activity and increase feed intake, which may improve feed efficiency and promote growth, respectively.

Dietary fatty acid (FA) composition has an impact on human health. There is an increasing request from consumers for healthier food and pork industry must respond to it without worsening performance and the technological properties of pork products. The inclusion of genetic markers for carcass FA composition in pig selection schemes could be a useful tool to reach the right balance between unsaturated and saturated FAs to satisfy market demands. With the aim of finding genomic regions associated with porcine backfat FA composition, a genome-wide association study was performed on 798 Italian Large White pigs genotyped using Illumina PorcineSNP60 k. The strongest associations with backfat contents of palmitic, palmitoleic, oleic, medium-chain and long-chain FAs were found for the Sus scrofa chromosome (SSC) 8 region located at 119 to 122 Mb, where the gene ELOVL FA elongase 6 is mapped. Palmitic, palmitoleic, stearic and oleic acid contents were also found associated with SSC14, in particular with the genomic region at 121 to 124 Mb, where stearoyl-CoA desaturase Δ9 gene lies. On the other hand, the genomic regions associated with backfat contents of arachidic, arachidonic, n-6 and n-3 FAs showed to harbour mainly genes involved in dietary lipids and carbohydrates digestion, absorption and utilisation. To our knowledge, this is the first study performed in Large White pigs identifying markers and genomic regions associated with backfat FA composition. The results validate in Large White some associations previously detected in other pig breeds and indicate the involvement of distinct metabolic pathways in the deposition pattern of essential and non-essential FAs.

Runs of homozygosity (ROH) are widely used as predictors of whole-genome inbreeding levels in cattle. They identify regions that have an unfavorable effect on a phenotype when homozygous, but also identify the genes associated with traits of economic interest present in these regions. Here, the distribution of ROH islands and enriched genes within these regions in four dairy cattle breeds were investigated. Cinisara (71), Modicana (72), Reggiana (168) and Italian Holstein (96) individuals were genotyped using the 50K v2 Illumina BeadChip. The genomic regions most commonly associated with ROHs were identified by selecting the top 1% of the single nucleotide polymorphisms (SNPs) most commonly observed in the ROH of each breed. In total, 11 genomic regions were identified in Cinisara and Italian Holstein, and eight in Modicana and Reggiana, indicating an increased ROH frequency level. Generally, ROH islands differed between breeds. The most homozygous region (>45% of individuals with ROH) was found in Modicana on chromosome 6 within a quantitative trail locus affecting milk fat and protein concentrations. We identified between 126 and 347 genes within ROH islands, which are involved in multiple signaling and signal transduction pathways in a wide variety of biological processes. The gene ontology enrichment provided information on possible molecular functions, biological processes and cellular components under selection related to milk production, reproduction, immune response and resistance/susceptibility to infection and diseases. Thus, scanning the genome for ROH could be an alternative strategy to detect genomic regions and genes related to important economic traits.

With increased regulations regarding the use of feed-grade antimicrobials in livestock systems, alternative strategies to enhance growth and immunity of feedlot cattle are warranted. Hence, this experiment compared performance, health and physiological responses of cattle supplemented with feed-grade antibiotics or alternative feed ingredients during the initial 60 days in the feedlot. Angus×Hereford calves (63 steers+42 heifers) originating from two cow–calf ranches were weaned on day −3, obtained from an auction yard on day −2 and road-transported (800 km; 12 h) to the feedlot. Upon arrival on day −1, shrunk BW was recorded. On day 0, calves were ranked by sex, source and shrunk BW, and allocated to one of 21 pens. Pens were assigned to receive (7 pens/treatment) a free-choice total mixed ration containing: (1) lasalocid (360 mg/calf daily of Bovatec; Zoetis, Florham Park, NJ, USA)+chlortetracycline (350 mg/calf of Aureomycin at cycles of 5-day inclusion and 2-day removal from diet; Zoetis) from days 0 to 32, and monensin only (360 mg/calf daily of Rumensin; Elanco Animal Health, Greenfield, IN, USA) from days 33 to 60 (PC), (2) sodium saccharin-based sweetener (Sucram at 0.04 g/kg of diet dry matter; Pancosma SA; Geneva, Switzerland)+plant extracts containing eugenol, cinnamaldehyde and capsicum (800 mg/calf daily of XTRACT Ruminants 7065; Pancosma SA) from days 0 to 32 and XTRACT only (800 mg/calf daily) from days 33 to 60 (EG) or (3) no supplemental ingredients (CON; days 0 to 60). Calves were assessed for bovine respiratory disease (BRD) signs and dry matter intake was recorded from each pen daily. Calves were vaccinated against BRD pathogens on days 0 and 22. Shrunk BW was recorded on day 61, and blood samples collected on days 0, 6, 11, 22, 33, 43 and 60. Calf ADG was greater (P=0.04) in PC v. EG and tended (P=0.09) to be greater in PC v. CON. Feed efficiency also tended (P=0.09) to be greater in PC v. CON, although main treatment effect for this response was not significant (P=0.23). Mean serum titers against bovine respiratory syncytial virus were greater in EG v. PC (P=0.04) and CON (tendency; P=0.08). Collectively, the inclusion of alternative feed ingredients prevented the decrease in feed efficiency when chlortetracycline and ionophores were not added to the initial feedlot diet, and improved antibody response to vaccination against the bovine respiratory syncytial virus in newly weaned cattle.

Mastitis can prove expensive in sheep reared for meat production due to costs associated with treatment methods, poor lamb growth and premature culling of ewes. The most commonly used method to detect mastitis, in dairy systems, is somatic cell counts. However, in many meat-producing sheep flocks ewes are not routinely handled, thus regular milk sampling is not always possible. It is, therefore, worthwhile to investigate alternative phenotypes, such as those associated with udder conformation and methods of evaluating somatic cell counts in the milk, such as the California Mastitis Test. The main objectives of this study were therefore: (a) to estimate genetic parameters of traits relating to mastitis and udder conformation in a meat sheep breed; (b) estimate the level of association between somatic cell counts and the California Mastitis Test and (c) assess the relationships between mastitis and both udder conformation and lamb live weights. Data were collected from Texel ewes based on 29 flocks, throughout the UK, during 2015 and 2016. The ewes were scored twice each year, at mid- and late-lactation. Eight different conformation traits, relating to udder and teat characteristics, and milk samples were recorded. The data set comprised of data available for 2957 ewes. The pedigree file used contained sire and dam information for 31 775 individuals. The animal models used fitted relevant fixed and random effects. Heritability estimates for traits relating to mastitis (somatic cell score and the California Mastitis Test), ranged from 0.08 to 0.11 and 0.07 to 0.11, respectively. High genetic correlations were observed between somatic cell score and the California Mastitis Test (0.76 to 0.98), indicating the California Mastitis Test to be worthwhile for assessing infection levels, particularly at mid-lactation. The strongest correlations observed between the mastitis traits and the udder conformation traits were associated with udder depth (0.61 to 0.75) also at mid-lactation. Negative phenotypic correlations were estimated between mastitis and the weight of lamb reared by the ewe (−0.15 to −0.23), suggesting that lamb weights fell as infection levels rose. Genetic correlations were not significantly different from zero. Reducing mastitis will lead to improvements in flock productivity and the health and welfare of the animals. It will also improve the efficiency of production and the resilience to disease challenge. The economic benefits, therefore, of these results combined could be substantial not only in this breed but also in the overall meat sheep industry.

Tail biting in domestic pigs relates to a range of risk factors, primarily in the pigs’ environment. Preventive tail docking is widely used, and various experimental approaches suggest that docking reduces the risk of tail biting. However, whether the docking length affects the prevalence of tail biting outbreaks is less studied, as is how a shortened tail will affect pigs’ social behaviour. The aim of this study was to investigate how three different tail docking lengths, measured at docking, as well as retained intact tails (Short: 2.9 cm; Medium: 5.7 cm; Long: 7.5 cm; and Undocked) affected tail biting risk and behaviour directed at other finisher pigs with the same docking length treatment. Tail lesions were scored weekly, as was behaviour at pen level after introduction to finisher pens and until a potential outbreak of tail biting or slaughter. Pigs from four commercial herds (258 litters) entered the study. Before the pigs entered the finisher section and data collection started, some pigs were excluded, mainly due to tail biting outbreaks in the weaner section. The risk of a tail biting outbreak differed significantly between treatments (P=0.001), with a lowered risk of a tail biting outbreak in Short pens compared with Undocked (P<0.001) and Medium (P<0.05), and was affected by herd as well (P<0.001). Pens in the Long and Undocked treatments were pooled for the behavioural analysis due to low representation, especially in the Undocked treatment. The probability of tail contacts, where a pig interacted with a pen mate’s tail, differed between docking length treatments and was highest in the Long/Undocked compared with the Short treatment (P<0.01), but docking length did not affect aggressive behaviour. Docking length affected the risk of a tail biting outbreak and the frequency of tail-directed behaviour in our participating herds, of which three reported a high prevalence of tail biting problems. Only the shortest docking length treatment (Short) reduced the tail biting risk, but did not completely prevent tail biting outbreaks.

Efficient and economical herd management depends a great deal on maintaining a short, well-defined calving season. This requires highly fertile females and bulls. Low pregnancy rates are very noticeable, however; potentially greater economic loss may be due to delayed conception. Many studies showed that approximately one of every five bulls had inadequate semen quality, physical soundness, or both, but when evaluation of serving capacity is included about one in four bulls is unsatisfactory. Due mainly to the time and expense that the market will bear, usually only physical soundness and semen quality are evaluated. Breeding soundness evaluation is a useful, low-cost screening method for reducing the risk of using low fertility bulls. The biggest problem with breeding soundness evaluations is not our lack of knowledge or ability, but in the willingness of veterinary schools to provide adequate equipment and training in this area, a lack of diagnostic laboratories equipped to handle the more difficult cases and, most importantly, the weaknesses of human nature that result in negligent testing procedure.

The aim of this review is to compare the performance of different reproductive programs using natural service, estrus synchronization treatment before natural service (timed natural breeding (TNB)), artificial insemination (AI) following estrus detection and timed artificial insemination (TAI) in beef herds. It is well known that after parturition the beef cow undergoes a period of anestrous, when they do not exhibit estrus, eliminating the opportunity to become pregnant in the early postpartum by natural mating or by AI after detection of estrus. Hormonal stimulation is already a consistent and well-proven strategy used to overcome postpartum anestrus in beef herds. Basically, hormones that normally are produced during the estrous cycle of the cow can be administered in physiological doses to induce cyclicity and to precisely synchronize follicular growth, estrus and ovulation. Furthermore, two options of mating may be used after hormonal stimulation: natural service (i.e. utilization of bull service after synchronization, referred to as TNB) and TAI. These strategies improve the reproductive efficiency of the herds compared with natural service without estrus induction or synchronization. After the first synchronized service, the most common strategy adopted to get non-pregnant cows pregnant soon is the introduction of clean-up bulls until the end of the breeding season. However, methods to resynchronize non-pregnant cows after the first service are already well established and offer a potential tool to reduce the time for subsequent inseminations. Thus, the use of these technologies enable to eliminate the use of bulls by using resynchronization programs (i.e. two, three or four sequential TAI procedures). The dissemination of efficient reproductive procedures, such as TNB, TAI and Resynch programs, either isolated or in combination, enables the production of a greater quantity (obtaining increased pregnancy rates early in the breeding season) and quality (maximization of the use of AI with superior genetic sires) of beef calves. These technologies can contribute to improve the production efficiency, and consequently, improve livestock profitability.

The advent of genomic selection has led to increased interest within the cattle breeding industry to market semen from young bulls as early as possible. However, both the quantity and quality of such semen is dictated by the age at which these animals reach puberty. Enhancing early life plane of nutrition of the bull stimulates a complex biochemical interplay involving metabolic and neuroendocrine signalling and culminating in enhanced testicular growth and development and earlier onset of sexual maturation. Recent evidence suggests that an enhanced plane of nutrition leads to an advancement of testicular development in bulls at 18 weeks of age. However, as of yet, much of the neuronal mechanisms regulating these developmental processes remain to be elucidated in the bull. While early life nutrition clearly affects the sexual maturation process in bulls, there is little evidence for latent effects on semen traits post-puberty. Equally the influence of prevailing nutritional status on the fertility of mature bulls is unclear though management practices that result in clinical or even subclinical metabolic disease can undoubtedly impact upon normal sexual function. Dietary supplements enriched with various polyunsaturated fatty acids or fortified with trace elements do not consistently affect reproductive function in the bull, certainly where animals are already adequately nourished. Further insight on how nutrition mediates the biochemical interaction between neuroendocrine and testicular processes will facilitate optimisation of nutritional regimens to optimise sexual maturation and subsequent semen production in bulls.

Lameness is one of the most costly dairy cow diseases, yet adoption of lameness prevention strategies remains low. Low lameness prevention adoption might be attributable to a lack of understanding regarding total lameness costs. In this review, we evaluated the contribution of different expenditures and losses to total lameness costs. Evaluated expenditures included labor for treatment, therapeutic supplies, lameness detection and lameness control and prevention. Evaluated losses included non-saleable milk, reduced milk production, reduced reproductive performance, increased animal death, increased animal culling, disease interrelationships, lameness recurrence and reduced animal welfare. The previous literature on total lameness cost estimates was also summarized. The reviewed studies indicated that previous estimates of total lameness costs are variable and inconsistent in the expenditures and losses they include. Many of the identified expenditure and loss categories require further research to accurately include in total lameness cost estimates. Future research should focus on identifying costs associated with specific lameness conditions, differing lameness severity levels, and differing stages of lactation at onset of lameness to provide better total lameness cost estimates that can be useful for decision making at both the herd and individual cow level.