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Chlamydiae are obligate intracellular bacteria that infect a broad range of host species, including sheep. Two species of Chlamydia infect sheep, C. abortus, which is a major cause of abortion in both sheep and goats, and C. pecorum, which causes pneumonia, arthritis/polyarthritis, encephalomyelitis, conjunctivitis, enteritis, abortion and metritis and infertility in domestic ruminants and pigs. The prevalence of faecal shedding of C. pecorum is relatively common amongst lambs in Australia. The aim of the work presented here was to use qPCR to determine the prevalence of C. pecorum in synovial samples obtained from abnormal joints trimmed from lamb carcases at one abattoir in southern Australia. The study included 53,131 carcases screened for arthritis, of which 369 had at least one abnormal joint trimmed. One hundred and forty eight trimmed joints were undamaged and suitable for PCR testing. The prevalence of C. pecorum in synovial tissue collected from the abnormal joints was 6.1% and the bacterial concentration ranged from 6 × 103 to 7.6 × 105/g of synovial tissue. Five of the positive joint samples were from carcases that had one joint trimmed for arthritis and four were from carcases from which two joints had been trimmed. None of the carcases from which the positive joint samples originated were condemned. The average arthritis trim weight of the carcases from which synovial tissue tested positive for C. pecorum was 1.112 kg (95% confidence interval 0.637-1.586 kg) and this did not differ from the carcases from which synovial tissue was not positive for C. pecorum. (mean 0.997 kg, 95% confidence interval 0.840-1.154 kg). Further research is required to determine the on-farm production losses associated with C. pecorum infection in Australian lambs.

Arthritis is commonly observed in lambs at slaughter, resulting in losses due to carcase downgrading, trimming or condemnation. The condition arises on-farm and is thought to be influenced by a number of predisposing factors, which vary in their ability to be addressed by sheep producers. The aim of this study was to investigate whether there is a link between tail length and arthritis in lambs. If there is, leaving a longer tail stump when docking may be a cost-effective way of reducing the prevalence of joint infections in lambs. The study was conducted at an abattoir in South Australia and included 63,287 carcases. This study found a correlation between short-docked tails (fewer than three coccygeal vertebrae remaining) and bacterial arthritis in lambs. Other risk factors for arthritis included breed and the regional source of the lambs, but not age. The constraints of data collection within the abattoir did not allow the effects of tail docking method, sex or whether male lambs had been castrated on the prevalence of bacterial arthritis to be determined. The bacterium most commonly isolated from abnormal joints was Erysipelothrix rhusiopathiae, followed by Streptococcus spp., including Streptococcus suis.

The objective of the present cross-sectional study was to determine whether antibodies against equine infectious anemia (EIA), equine viral arteritis (EVA), and Burkholderia mallei in horses from Jordan can be detected at all; moreover, the study aimed at identifying potential risk factors associated with a positive serologic result. Data related to management of each farm and individual horses were collected. Commercially available serologic kits were used to detect the presence of serum antibodies in 254 horses. Potential risk factors associated with seropositivity were evaluated using the one-sided chi square tests of association. All serum samples were negative for equine infectious anemia virus and glanders. Therefore, no risk factors could be determined. A total of 6 (2.4%) sera had antibodies to equine arteritis virus (EAV). There was a significant ( P P P

This study aimed to determine the seroprevalence and to identify risk factors associated with Neospora spp. infection in horses in Jordan. Management related data were collected from each farm and individual horses. Sera from 227 horses from 5 of 6 climatic regions in Jordan were analyzed for the presence of antibodies to Neospora spp. by ELISA kit. The study was performed during spring of 2010. The association between seropositivity and risk factors was analyzed. A total of 7 (3%) of 227 sera had antibodies for Neospora spp. There was a significant regional difference (P=0.018) between the 5 climatic regions. Positive cases were located in Amman and Irbid, while the other regions (Zarqa, Jordan Valley, and Wadi Mousa) had zero prevalence. The use of anthelmintics at least once a year resulted in a significant reduction of the seroprevalence to Neospora spp. (1.6% vs 9.8%). However, this might be a phenomenon by chance and a better hygiene since owners can invest in anthelmintics. Other risk factors such as age, gender, breed, usage, body condition score, grazing, presence of other animals mixed with the horses in the same property, and a history of previous diseases were not significantly associated with the seroprevalence to Neospora spp. infection. This is the first study to report on the presence of Neospora seropositive horses in Jordan. Further studies are warranted to better understand the role of certain risk factors in the transmission of Neospora spp. among horse population and to determine which Neospora spp. are responsible for the infection.

Bacterial arthritis in sheep is a painful and debilitating condition that is widespread across all sheep-raising regions and climatic zones of Australia. At slaughter, bacterial arthritis in sheep causes economic losses through the condemnation of all or parts of the carcass, as specified in the Australian Standard for the Hygienic Production and Transportation of Meat and Meat Products for Human Consumption. In this study, we investigated the economic cost of arthritis in lambs presenting to an abattoir in southern Australia using a combination of the prevalence of arthritis detected during meat inspection, condemnation rates, trim weight and carcass weight, and fat measurements. Data were collected on 354 lines of lambs representing 63287 carcasses. One hundred and sixty nine consignments, or approximately one-half of the consignments, had at least one carcass with arthritis/polyarthritis detected by meat inspection personnel. Four hundred and twenty-two, or 0.7%, of the carcasses had arthritis/polyarthritis in at least one joint. When arthritis was present, on average 2.0% of the line was affected. Three carcasses with arthritis were condemned and the remainder trimmed, with an average trim weight of 0.7 kg. In addition, arthritis reduced the growth of lambs by 1.2 kg hot standard carcass weight, approximately 2.7 kg liveweight (assuming 45% dressing percentage) and reduced fat cover by 1.8 mm.

High hydrostatic pressure (300, 450 and 600 MPa) was used to investigate its effect on microbial population, meat quality and sensory characteristics of chicken breast fillets. Pressures of 450 and 600 MPa almost completely eliminated all the 3 major pathogens Salmonella typhimurium (KCTC 1925), Escherichia coli (KCTC 1682), and Listeria monocytogenes (KCTC 3569) and therefore improved safety of chicken breast fillets. The 600 MPa treatment reduced bacteria count by 6–8 log (CFU/g) for 7–14 days, and the 450 MPa treatment reduced bacteria count by 4–8 log (CFU/g) for 3–14 days, depending on the microorganism. The increased pressure had an impact on flavour, aroma strength and juiciness. The 300 MPa pressure significantly reduced flavour, aroma strength and juiciness, and 450 MPa produced breast fillets with the weakest aroma. Increasing pressure increased cooking loss and colour by increasing L*, a* and b* values. Moreover, elevated pressure increased hardness, cohesiveness, gumminess and chewiness, as well as improved freshness of meat by reducing VBN. Pressure of 450 MPa and higher induced lipid oxidation. The results demonstrate that high pressure treatment is an effective technology in reducing bacterial spoilage and extending shelf-life of chicken breast fillet, however it may have a negative impact on some quality and sensory characteristics.

Postnatal myofibre characteristics and muscle mass are largely determined during fetal development and may be significantly affected by epigenetic parent-of-origin effects. However, data on such effects in prenatal muscle development that could help understand unexplained variation in postnatal muscle traits are lacking. In a bovine model we studied effects of distinct maternal and paternal genomes, fetal sex, and non-genetic maternal effects on fetal myofibre characteristics and muscle mass. Data from 73 fetuses (Day153, 54% term) of four genetic groups with purebred and reciprocal cross Angus and Brahman genetics were analyzed using general linear models. Parental genomes explained the greatest proportion of variation in myofibre size of Musculus semitendinosus (80-96%) and in absolute and relative weights of M. supraspinatus, M. longissimus dorsi, M. quadriceps femoris and M. semimembranosus (82-89% and 56-93%, respectively). Paternal genome in interaction with maternal genome (P

The placenta, a major determinant of fetal growth in eutherians, facilitates maternal-fetal cross talk and mediates programming of postnatal phenotype via genetic and epigenetic mechanisms. However, magnitude and specificity of effects of maternal and paternal genomes on placental and fetal phenotype and their relationships are unclear. Using an outbred bovine intra-species model with well-defined Bos taurus taurus and Bos taurus indicus maternal and paternal genetics, we generated purebred and reciprocal cross fetuses (Animal Ethics No. S-094-2005) to dissect and quantify effects of parental genomes, fetal sex, and nongenetic maternal effects (maternal weight and post-conception maternal weight gain) on 41 gross and histomorphological feto-placental parameters. Analysis of data from 73 fetuses recovered at midgestation (Day 153) with general linear models (Xiang et al. 2014 JBMR http://dx.doi.org/10.1002/jbmr.2263) using the GLM procedure of R version 22.14 (R Development Core Team, Vienna, Austria) revealed that maternal and paternal genome combined explained the highest proportion of variation (47.2–99.5%) in 30 investigated parameters with significant (P

During a 4-year period (1994–97) of the Australian ‘Southern Crossbreeding Project’, mature Hereford cows (n = 637) were mated to 97 sires from 7 breeds (Jersey, Wagyu, Angus, Hereford, South Devon, Limousin and Belgian Blue), resulting in 1334 calves. Heifers were slaughtered at around 16 months and steers at 23 months. The objective of the study was to quantify between- and within-breed genetic variation for numerous production and quality traits in a southern-Australian production system. Calf survival, birth weight and carcass production traits (carcass weight, fat depth, loin eye area, intramuscular fat) were obtained from these cattle. The carcass traits were loge-transformed because of a scale effect on the variance. Data were analysed using multi-variate animal models containing fixed effects of sex with random effects of management group, sire breed and animal. In addition, birth month and age of dam were included as fixed effects for birth weight. Covariances between survival and other traits could not be estimated from the multi-variate model so they were estimated from a series of bi-variate models. On average, management group and sire breed accounted for similar proportions of variance. Heritability ranged from 0.14 (survival), 0.17 (intramuscular fat), 0.28 (loin eye area), 0.29 (P8 fat depth), 0.31 (birth weight) to 0.50 (carcass weight). In general, environmental (management and residual) correlations between meat (carcass weight and loin eye area) and fat traits (fat depth and intramuscular fat) were positive, but the genetic correlations (both between and within breed) were negative. Management and genetic (co)variation has been quantified and can facilitate production of calves with carcasses suitable for specific market requirements.