Veterinary Science Collected Works - Research Publications
Permanent URI for this collection
Search Results
1 - 5 of 5
-
ItemNo Preview Available
-
ItemAmmonia volatilisation losses from urea applied to acidic cropping soils is regulated by pH buffering capacity(CSIRO Publishing, 2023)Ammonia (NH3) volatilisation can be a significant nitrogen (N) loss pathway in the grains industry following the surface broadcast application of urea. However, the extent of urea volatilisation from acidic soils and the soil properties that regulate this N loss pathway have not been investigated widely. Aims. We conducted a laboratory incubation experiment to measure NH3 volatilisation loss potential following the broadcast application of urea prills (1–2mm diameter; 50 kg N ha−1) onto moistened acidic and neutral cropping soils, sampled from four long-term cropping research sites. Methods. The selected soils varied in pH, clay content, organic carbon, pH buffering capacity (pHBC) and cation exchange capacity. Volatilised NH3 was captured in a phosphoric acid trap after 7, 14 and 21 days and then measured using colorimetric analysis. We compared the measured NH3 losses with predicted NH3 losses derived from an existing empirical NH3 volatilisation prediction model. Key results. Of the applied urea-N, 0.9–25% was volatilised. Cumulative NH3 losses were strongly related (R2 = 0.77) with soil pHBC derived from a pedotransfer function. The existing NH3 loss model generally had poor predictive capacity (RMSE = 34%). Conclusions. Using clay content as a surrogate variable for pHBC in the predictive model for sandy kaolinitic soils where it is largely a function of organic carbon content can cause poor estimates of NH3 volatilisation loss potential. Implications. Grain production on sandy, acidic soils with low pHBC could lead to substantial NH3 volatilisation losses if urea is broadcast.
-
ItemOutcome following emergency laparotomy in 33 UK donkeys: A retrospective multicentre study(WILEY, 2023-03)BACKGROUND: Emergency laparotomies in donkeys are infrequently performed and there is limited literature on the subject. OBJECTIVES: To determine findings and associated outcomes of exploratory laparotomies in donkeys. STUDY DESIGN: Descriptive retrospective study. METHODS: Donkeys undergoing emergency exploratory laparotomy for investigation and treatment of colic at seven UK referral hospitals between 2005-2017 were included. Data were retrieved from available hospital records. Descriptive statistics and inferential statistical analysis of outcomes of interest was performed in three steps. RESULTS: Thirty-three cases fulfilled the inclusion criteria. Clinical signs on presentation were available for 32 donkeys, of which 53.1% (17/32) presented for investigation of colic while in 46.9% (15/32) the presenting complaint was non-specific. Primary lesion location included small intestine (42.4%, 14/33), large colon (39.3%, 13/33), caecum (6.1%, 2/33), stomach (6.1%, 2/33) and 6.1% (2/33) had multiple abnormal findings without a clear primary lesion. Overall survival to discharge was 54.5% (18/33). Five donkeys (15.2%, 5/33) were euthanased at surgery and of those recovering from general anaesthesia a further 35.7% (10/28) were euthanased or died prior to discharge. Six donkeys (21.4%, 6/28) required a second laparotomy of which 4 (66.7%, 4/6) survived. Post-operative complications occurred in 82.1% (23/28) of cases and included hyperlipaemia (42.9%, 12/28), incisional complications (21.4%, 6/28), ileus (21.4%, 6/28) and persistent colic (17.9%, 5/28). When adjusted for other complications, donkeys with primary gastric lesions were less likely to have presented with severe colic compared with those with primary small intestinal lesions (OR: 0.07, 95% CI 0.01-0.95, p = 0.05). Only age was positively associated with death prior to discharge (OR: 1.18, 95% CI 1.03-1.36, p = 0.02). MAIN LIMITATIONS: Small sample size and retrospective design. CONCLUSION: Donkeys with abdominal lesions may present with a range of signs often not including colic. Surgical findings were diverse and survival to discharge appears to be lower than in horses.
-
ItemCross-species emotional political ecology in rural Pakistan(Elsevier, 2023-02-01)This article engages cross-species intersectionality and emotional political ecology to evaluate a dairy extension service that ran in Punjab and Sindh, Pakistan, between 2012 and 2017. The project aimed to mitigate potential negative impacts of implementation, such as the exacerbation of pre-existing social inequality, by applying principles of women’s agency and empowerment in project design. Evidence from the two case study villages reveals how social difference (caste and class) shape women’s access to extension meetings and the resources to implement practices. The evidence also reveals that through cattle work woman cultivate an emotional bond with their animals, given the multiple instrumental and sociocultural values they represent for households. Singh (2013) provides a definition of the agentic potential of this emotional bond as the ‘ability to affect and be affected.’ The higher socioeconomic classes that had good access to the extension service were able to improve animal welfare and milk production through which they cultivated satisfaction, pride and independence. Alternatively, women expressed feelings of longing or boredom in the absence of this invaluable resource in their lives. This article confirms the importance of intersectionality for designing interventions that are sensitive to inter and intra household dynamics and that cross-species relations form pivotal axes for social difference. These cross-species relations cultivate emotions/affect during engagement with the extension service.
-
ItemImmature Brain Cortical Neurons Have Low Transcriptional Competence to Activate Antiviral Defences and Control RNA Virus Infections(KARGER, 2023)Virus infections of the central nervous system (CNS) cause important diseases of humans and animals. As in other tissues, innate antiviral responses mediated by type I interferons (IFNs) are crucially important in controlling CNS virus infections. The maturity of neuronal populations is an established critical factor determining the outcome of CNS virus infection. Using primary cultures of mouse cortical neurons, we investigated the relationships between neuronal maturation, type I IFN responses, and the outcome of Semliki Forest virus infection. The virus replicated better, infected more cells, and produced higher titres of infectious viruses in immature neurons. Complete transcriptome analysis demonstrated that resting immature neurons have low transcriptional competence to mount antiviral responses. They had no detectable transcription of the genes Ddx58 and Ifih1, which encode key RNA virus cytoplasmic sensors RIG-I and MDA5, and very low expression of genes encoding key regulators of associated signalling pathways. Upon infection, immature neurons failed to mount an antiviral response as evidenced by their failure to produce chemokines, IFNs, and other cytokines. Treatment of immature neurons with exogenous IFNβ prior to infection resulted in antiviral responses and lower levels of virus replication and infectious virus production. In contrast, resting mature neurons generated a robust antiviral response. This was augmented by pretreatment with IFNβ. Infection of mature neurons derived from IFNAR-/- mice did not make an antiviral response and replicated virus to high levels.