Search

Context. Heat stress is an increasing concern for the Australian dairy industry. Aims. This study aimed to evaluate the effect of temperature–humidity index (THI) on rumination time (RT), milk yield and quality, and milking frequency in a pasture-based voluntary-movement automatic milking system (AMS). Methods. Data were collected from the University of Melbourne Dookie College AMS farm for 3 years (June 2016 to March 2019). Daily RT was collected through the transponder collar (Qwes-HR, Lely). Climatic data (maximum ambient temperature and relative humidity) were obtained from the Dookie Meteorological station to calculate daily maximum THI (THImax). Key results. Daily milk yield increased with a rising THImax to 65, then declined after THImax 65. Milking frequency was highest at THImax 90, followed by a steady decline afterwards. Rumination time was maximum at mid-range THImax and declined for high and low values. Conclusions. The findings of this study clearly indicated that under pasture-based voluntary-movement AMS, high THI resulted in a drop in the milk yield, milking frequency and RT. Implications. With the provision of automation of data collection from AMS, further study with mathematical modelling describing the daily patterns and thresholds in conjunction with the different heat stress levels can be useful for assessing animal welfare and to mitigate heat stress and seek alternative management strategies.

This study aimed to evaluate the sensory and physical characteristics of zingibain-injected meat combined with sous vide cooking. M. biceps femoris (BF; n = 12) acquired from 6-7 year old Angus cows were cooked using the sous vide method at 65 °C, for 8 h or 12 h, either with ginger powder (GP) injected in a 2 g/L solution in water (treatment) or un-injected (control). The sensory attributes included flavour, juiciness, tenderness, and physicochemical characteristics were Warner-Bratzler shear (WBSF), hardness, total water content (TWC), cooking loss (CL) and collagen content. A significant improvement in tenderness with injection treatment and cooking time was observed, as evaluated through trained sensory panellists, and reduced WBSF and hardness (p < 0.05 for all). The flavour of the meat was not affected by injection treatment or cooking time (p > 0.05), but juiciness and TWC were reduced with longer cooking times (p < 0.01 for both). Soluble collagen increased with injection treatment and cooking time (both p < 0.05). Moderate to high correlations were found between sensory and physical measurements for tenderness and juiciness. The longer cooking time (12 h) with GP injection treatment caused over tenderization of the meat. The soft texture associated with over-tenderization may be suitable for some specialised consumer markets, for instance, the elderly population with chewing difficulties. Improving the eating quality of low-quality meat from old animals through sous vide cooking and the use of ginger proteases may increase the acceptability of lower value beef, potentially enhancing the commercial value of carcasses typically produced in the beef industry.

INTRODUCTION: Childhood diarrhoeal diseases and stunting are major health problems in low- and middle-income countries (LMICs). Poor water supply, sanitation services and hygiene, frequently encountered in resource-poor settings, contribute to childhood diarrhoea and stunting. METHODS: Data on demographic characteristics, hygiene practices, sanitation and human-animal interactions (predictors) and child height-for-age z-scores (HAZ) (outcome) were collected once, while diarrhoea incidences were collected fortnightly for 24 months (outcome). RESULTS: Drinking water from public taps (OR = 0.51, 95% CI. 0.44-0.61; p < 0.001) and open wells (OR = 0.46, 95% CI. 0.39-0.54; p < 0.001) and older age of children (OR = 0.43, 95% CI. 0.27-0.67; p < 0.001) were protective against diarrhoea. Inappropriate disposal of children's faeces (OR = 1.15, 95% CI. 1.02-1.31; p = 0.025), sharing water sources with animals in the dry season (OR = 1.48, 95% CI. 1.29-1.70; p < 0.001), overnight sharing of houses with cats (OR = 1.35, 95% CI. 1.16-1.57; p < 0.001) and keeping chickens inside the house overnight regardless of room (OR = 1.39, 95% CI. 1.20-1.60; p < 0.001) increased the risk of diarrhoea. The Sukuma language group (p = 0.005), washing hands in running water (p = 0.007), access of chickens to unwashed kitchen utensils (p = 0.030) and overnight sharing of the house with sheep (p = 0.020) were associated with higher HAZ in children. CONCLUSIONS: Until a more precise understanding of the key risk factors is available, these findings suggest efforts towards control of diarrhoea and improved linear growth in these areas should be directed to increased access to clean and safe water, hand-washing, sanitation, and improved animal husbandry practices.

A cross‐sectional study was conducted to estimate the seroprevalence of bovine brucellosis in smallholder farms in seven regions in Pakistan, identify herd and individual level risk factors for seropositivity and assess the level of engagement of farmers with risk factors. In total, 1063 cattle and buffalo belonging to 420 herds in seven districts were sampled. The Rose Bengal test (RBT), indirect enzyme‐linked immunosorbent assay (I‐ELISA) and competitive enzyme‐linked immunosorbent assay (C‐ELISA) were used for the serological diagnosis of bovine brucellosis on all the serum samples. The associations between herd‐and animal‐level risk factors and seropositivity were investigated using logistic regression analyses. In addition, herd management practice scores, created to quantify the number of management practices undertaken that pose a risk for Brucella transmission, were calculated and compared between seropositive and negative herds within each district. Overall herd and animal prevalence were estimated to be 16.2% (95% CI, 13–20%) and 8.7% (95% CI, 7.2–10.6%), respectively, across all districts sampled. Herds with a history of last trimester abortion were found to be more likely to be positive than herds without such history (OR = 2.06, 95% CI, 1.09–3.89), providing validation of our findings and identifying that clinical disease is occurring in this region. It was also identified that herds with five to eight buffalo (OR = 3.80, 95% CI, 1.69–8.49), and those with more than eight buffalo (OR = 3.81, 95% CI, 1.51–9.58) were more likely to be positive for Brucella than those with less (one to two and three to four) buffaloes present in the herd. The presence of other domestic animals at the farm and purchasing animals in last year were found to have no association with seropositivity. The findings of this study support the need for the development of targeted intervention strategies specific to the disease status of each district.

There is substantial current interest in linkages between livestock-keeping and human nutrition in resource-poor settings. These may include benefits of improved diet quality, through animal-source food consumption and nutritious food purchases using livestock-derived income, and hazards of infectious disease or environmental enteric dysfunction associated with exposure to livestock feces. Particular concerns center on free-roaming chickens, given their proximity to children in rural settings, but findings to date have been inconclusive. This longitudinal study of 503 households with a child under 24 months at enrolment was conducted in villages of Manyoni District, Tanzania between May 2014, and May 2016. Questionnaires encompassed demographic characteristics, assets, livestock ownership, chicken housing practices, maternal education, water and sanitation, and dietary diversity. Twice-monthly household visits provided information on chicken numbers, breastfeeding and child diarrhea, and anthropometry was collected six-monthly. Multivariable mixed model analyses evaluated associations between demographic, socioeconomic and livestock-associated variables and (a) maternal and child diets, (b) children's height-for-age and (c) children's diarrhea frequency. Alongside modest contributions of chicken-keeping to some improved dietary outcomes, this study importantly (and of substantial practical significance if confirmed) found no indication of a heightened risk of stunting or greater frequency of diarrhea being associated with chicken-keeping or the practice of keeping chickens within human dwellings overnight.

Suboptimal breastfeeding practices, early initiation of complementary feeding, and monotonous cereal-based diets have been implicated as contributors to continuing high rates of child undernutrition in sub-Saharan Africa. Nutrition-sensitive interventions, including agricultural programs that increase access to nutrient-rich vegetables, legumes, and animal-source foods, have the potential to achieve sustainable improvements in children's diets. In the quest to evaluate the efficacy of such programs in improving growth and development in the first 2 years of life, there is a role for mixed methods research to better understand existing infant and young child feeding practices. This analysis forms part of a longitudinal study assessing the impact of improvements to poultry health and crop production on diets and growth of 503 randomly selected children from eight rural communities in Manyoni District in central Tanzania. Using an explanatory sequential design, the quantitative phase of data collection was conducted between May 2014 and May 2016, comprising six monthly structured questionnaires, four monthly household-level documentation of chicken and egg consumption, and fortnightly records of children's breastfeeding status. The subsequent qualitative phase involved in-depth interviews with a subset of 39 mothers in October 2016. Breastfeeding was almost universal (96.8%) and of long duration (mean = 21.7 months, SD = 3.6), but early initiation of complementary feeding was also common (74.4%; mean = 4.0 months, SD = 1.8), overwhelmingly driven by maternal perceptions of insufficient milk supply (95.0%). Chicken and eggs were infrequently eaten, but close associations between maternal and child consumption patterns (p < .001) suggest the potential for strategies that increase household-level consumption to bring nutritional benefits to young children.

Newcastle disease (ND) is a viral disease of poultry with global importance, responsible for the loss of a potential source of household nutrition and economic livelihood in many low-income food-deficit countries. Periodic outbreaks of this endemic disease result in high mortality amongst free-ranging chicken flocks and may serve as a disincentive for rural households to invest time or resources in poultry-keeping. Sustainable ND control can be achieved through vaccination using a thermotolerant vaccine administered via eyedrop by trained "community vaccinators". This article evaluates the uptake and outcomes of fee-for-service ND vaccination programs in eight rural villages in the semi-arid central zone of Tanzania. It represents part of an interdisciplinary program seeking to address chronic undernutrition in children through improvements to existing poultry and crop systems. Newcastle disease vaccination uptake was found to vary substantially across communities and seasons, with a significantly higher level of vaccination amongst households participating in a longitudinal study of children's growth compared with non-participating households (p = 0.009). Two multivariable model analyses were used to explore associations between vaccination and chicken numbers, allowing for clustered data and socioeconomic and cultural variation amongst the population. Results demonstrated that both (a) households that undertook ND vaccination had a significantly larger chicken flock size in the period between that vaccination campaign and the next compared with those that did not vaccinate (p = 0.018); and (b) households with larger chicken flocks at the time of vaccination were significantly more likely to participate in vaccination programs (p < 0.001). Additionally, households vaccinating in all three vaccination campaigns held over 12 months were identified to have significantly larger chicken flocks at the end of this period (p < 0.001). Opportunities to understand causality

The present study aimed to assess the extent of knowledge and understanding of brucellosis in smallholder dairy farmers and identify practices at the farm and household level that might pose a risk for humans contracting brucellosis. Between February and June 2015 a cross-sectional study was conducted among smallholder farms (n = 420) in five districts of Punjab and two districts of Sindh province. Farmers were interviewed using a questionnaire to obtain information on farmers' knowledge about brucellosis and the potential risks for contracting the disease that are present for dairy farmers and their families. Logistic regression and ordinal logistic models were used to investigate potential predictors for risky behaviours. The results show almost all farmers (97%) were not aware of the modes of transmission of brucellosis. Relating to risk, the majority (66%) of the farmers' families were reported to consume raw milk and its products, live in shared housing with animals (49%) and not cover hand cuts during contact with animals (74%). All farmers performed at least one risky practice on a regular basis for brucellosis transmission from animal to human. A multivariable analysis highlighted that the respondents with no formal education and those who had not heard of the disease displayed greater risky behaviour. Poor understanding of the disease, presence of multiple risky practices on farm and at the household, and incorrect perception supports the need for an educational awareness program in order to ensure uptake of improved practices.

BACKGROUND: In developing dairy sectors, genetic improvement programs have limited resources and recording of herds is minimal. This study evaluated different methods to estimate lactation yield and sampling schedules with fewer test-day records per lactation to determine recording regimes that (1) estimate lactation yield with a minimal impact on the accuracy of selection and (2) optimise the available resources. METHODS: Using Sahiwal cattle as a tropical dairy breed example, weekly milk records from 464 cows were used in a simulation study to generate different shaped lactation curves. The daily milk yields from these simulated lactation curves were subset to equally spaced (weekly, monthly and quarterly) and unequally spaced (with four, five or six records per lactation) test-day intervals. Lactation yield estimates were calculated from these subsets using two methods: the test-interval method and Wood's (Nature 216:164-165, 1967) lactation curve model. Using the resulting lactation yields, breeding values were predicted and comparisons were made between the sampling regimes and estimation methods. RESULTS: The results show that, based on the mean square error of prediction, use of Wood's lactation curve model to estimate total yield was more accurate than use of the test-interval method. However, the differences in the ranking of animals were small, i.e. a 1 to 5% difference in accuracy. Comparisons between the different test-day sampling regimes showed that, with the same number of records per lactation (for example, quarterly and four test-days), strategically timed test-days can result in more accurate estimates of lactation yield than test-days at equal intervals. CONCLUSIONS: An important outcome of these results is that combining Wood's model for lactation yield estimation and as few as four, five or six strategically placed test-day records can produce estimates of lactation yield that are comparable with estimates based on monthly test-day records using

BACKGROUND: In addition to probe sequence characteristics, noise in hybridization array data is thought to be influenced by competitive hybridization between probes tiled at high densities. Empirical evaluation of competitive hybridization and an estimation of what other non-sequence related features might affect noisy data is currently lacking. RESULTS: A high density array was designed to a 1.5 megabase region of the canine genome to explore the potential for probe competition to introduce noise. Multivariate assessment of the influence of probe, segment and design characteristics on hybridization intensity demonstrate that whilst increased density significantly depresses fluorescence intensities, this effect is largely consistent when an ultra high density offset is applied. Signal variation not attributable to sequence composition resulted from the reduction in competition when large inter-probe spacing was introduced due to long repetitive elements and when a lower density offset was applied. Tiling of probes immediately adjacent to various classes of repeat elements did not generate noise. Comparison of identical probe sets hybridized with DNA extracted from blood or saliva establishes salivary DNA as a source of noise. CONCLUSIONS: This analysis demonstrates the occurrence of competitive hybridization between oligonucleotide probes in high density tiling arrays. It supports that probe competition does not generate random noise when it is maintained across a region. To prevent the introduction of noise from this source, the degree of competition should be regulated by minimizing variation in density across the target region. This finding can make an important contribution to optimizing coverage whilst minimizing sources of noise in the design of high density tiling arrays.

BACKGROUND: The marsupial early lactation protein (ELP) gene is expressed in the mammary gland and the protein is secreted into milk during early lactation (Phase 2A). Mature ELP shares approximately 55.4% similarity with the colostrum-specific bovine colostrum trypsin inhibitor (CTI) protein. Although ELP and CTI both have a single bovine pancreatic trypsin inhibitor (BPTI)-Kunitz domain and are secreted only during the early lactation phases, their evolutionary history is yet to be investigated. RESULTS: Tammar ELP was isolated from a genomic library and the fat-tailed dunnart and Southern koala ELP genes cloned from genomic DNA. The tammar ELP gene was expressed only in the mammary gland during late pregnancy (Phase 1) and early lactation (Phase 2A). The opossum and fat-tailed dunnart ELP and cow CTI transcripts were cloned from RNA isolated from the mammary gland and dog CTI from cells in colostrum. The putative mature ELP and CTI peptides shared 44.6%-62.2% similarity. In silico analyses identified the ELP and CTI genes in the other species examined and provided compelling evidence that they evolved from a common ancestral gene. In addition, whilst the eutherian CTI gene was conserved in the Laurasiatherian orders Carnivora and Cetartiodactyla, it had become a pseudogene in others. These data suggest that bovine CTI may be the ancestral gene of the Artiodactyla-specific, rapidly evolving chromosome 13 pancreatic trypsin inhibitor (PTI), spleen trypsin inhibitor (STI) and the five placenta-specific trophoblast Kunitz domain protein (TKDP1-5) genes. CONCLUSIONS: Marsupial ELP and eutherian CTI evolved from an ancestral therian mammal gene before the divergence of marsupials and eutherians between 130 and 160 million years ago. The retention of the ELP gene in marsupials suggests that this early lactation-specific milk protein may have an important role in the immunologically naïve young of these species.

BACKGROUND: In sheep dairy production, total lactation performance, and length of lactation of lactation are of economic significance. A more persistent lactation has been associated with improved udder health. An extended lactation is defined by a longer period of milkability. This study is the first investigation to examine the presence of quantitative trait loci (QTL) for extended lactation and lactation persistency in sheep. METHODS: An (Awassi × Merino) × Merino single-sire backcross family with 172 ewes was used to map QTL for lactation persistency and extended lactation traits on a framework map of 189 loci across all autosomes. The Wood model was fitted to data from multiple lactations to estimate parameters of ovine lactation curves, and these estimates were used to derive measures of lactation persistency and extended lactation traits of milk, protein, fat, lactose, useful yield, and somatic cell score. These derived traits were subjected to QTL analyses using maximum likelihood estimation and regression analysis. RESULTS: Overall, one highly significant (LOD > 3.0), four significant (2.0 < LOD < 3.0) and five suggestive (1.7 < LOD < 2.0) QTL were detected across all traits in common by both mapping methods. One additional suggestive QTL was identified using maximum likelihood estimation, and four suggestive (0.01 < P < 0.05) and two significant (P < 0.01) QTL using the regression approach only. All detected QTL had effect sizes in the range of 0.48 to 0.64 SD, corresponding to QTL heritabilities of 3.1 to 8.9%. The comparison of the detected QTL with results in cattle showed conserved linkage regions. Most of the QTL identified for lactation persistency and extended lactation did not coincide. This suggests that persistency and extended lactation for the same as well as different milk yield and component traits are not controlled by the same genes. CONCLUSION: This study identified ten novel QTL for lactation persistency and extended lactation in sheep, b

An (Awassi x Merino) x Merino backcross family of 172 ewes was used to map quantitative trait loci (QTL) for different milk production traits on a framework map of 200 loci across all autosomes. From five previously proposed mathematical models describing lactation curves, the Wood model was considered the most appropriate due to its simplicity and its ability to determine ovine lactation curve characteristics. Derived milk traits for milk, fat, protein and lactose yield, as well as percentage composition and somatic cell score were used for single and two-QTL approaches using maximum likelihood estimation and regression analysis. A total of 15 significant (P < 0.01) and additional 25 suggestive (P < 0.05) QTL were detected across both single QTL methods and all traits. In preparation of a meta-analysis, all QTL results were compared with a meta-assembly of QTL for milk production traits in dairy ewes from various public domain sources and can be found on the ReproGen ovine gbrowser http://crcidp.vetsci.usyd.edu.au/cgi-bin/gbrowse/oaries_genome/. Many of the QTL for milk production traits have been reported on chromosomes 1, 3, 6, 16 and 20. Those on chromosomes 3 and 20 are in strong agreement with the results reported here. In addition, novel QTL were found on chromosomes 7, 8, 9, 14, 22 and 24. In a cross-species comparison, we extended the meta-assembly by comparing QTL regions of sheep and cattle, which provided strong evidence for synteny conservation of QTL regions for milk, fat, protein and somatic cell score data between cattle and sheep.

BACKGROUND: A wide variety of animal models have been used to study human breast cancer. Murine, feline and canine mammary tumor cell lines have been studied for several decades and have been shown to have numerous aspects in common with human breast cancer. It is clear that new comparative approaches to study cancer etiology are likely to be productive. RESULTS: A continuous line of breast carcinoma cells (WalBC) was established from a primary breast cancer that spontaneously arose in a female tammar wallaby (Macropus eugenii). The primary tumor was 1.5 cm3 and although large, did not appear to invade the stroma and lacked vimentin expression. The WalBC cell line was cultured from the primary tumor and passaged for 22 months. WalBC cells displayed an epithelial morphology when grown on plastic, were not EGF responsive, stained strongly for cyto-keratin and negatively for vimentin. WalBC cells were shown to be non-invasive within a Matrigel invasion assay and failed to produce tumors following transplantation into nude mice. Gene expression profiling of WalBC cells was performed using a cDNA microarray of nearly 10,000 mammary gland cDNA clones and compared to normal primary mammary cells and profiles of human breast cancer. Seventy-six genes were down-regulated and sixty-six genes were up-regulated in WalBC cells when compared to primary mammary cells. WalBC cells exhibited expression of known markers of basal invasive human breast cancers as well as increased KRT17, KRT 14 and KRT 19, DSP, s100A4, NDRG-1, ANXA1, TK1 and AQP3 gene expression and decreased gene expression of TIMP3, VIM and TAGLN. New targets for breast cancer treatment were identified such as ZONAB, PACSIN3, MRP8 and SUMO1 which have human homologues. CONCLUSION: This study demonstrates how novel models of breast cancer can provide new fundamental clues regarding cancer etiology which may lead to new human treatments and therapies.