Selection of ancillary data to derive production management units in sweet corn (<Emphasis Type="Italic">Zea Mays</Emphasis> var. rugosa) using MANOVA and an information criterion     

J. A. Taylor  B. M. Whelan 《Precision Agriculture》2011,12(4):519-533

In production systems where high-resolution harvest data are unavailable there is often a reliance on ancillary information to generate potential management units. In these situations correct identification of relevant sources of data is important to minimize cost to the grower. For three fields in a sweet corn production system in central NSW, Australia, several sets of high-resolution data were obtained using soil and crop canopy sensors. Management units were derived by k-means classification for 2–5 classes using three approaches: (1) with soil data, (2) with crop data and (3) a combination of both soil and crop data. Crop quantity and quality were sampled manually, and the sample data were related to the different management units using multivariate analysis of variance (MANOVA). The corrected Akaike information criterion (AICc) was then used to rank the different sources of data and the different orders of management units. For irrigated, short-season sweet corn production the management units derived from the crop canopy sensor data explained more variation in key harvest variables than management units derived from an apparent soil electrical conductivity (EC_a) survey or a mixture of crop and soil sensor data. Management units derived from crop data recorded just prior to side-dressing outperformed management units derived from data recorded earlier in the season. However, multi-temporal classification of early and mid-season crop data gave better results than single layer classification at any time. For all three fields in this study, a 3- or 4-unit classification gave the best results according to the information criterion (AICc). For growers interested in adopting differential management in irrigated sweet corn, investment in a crop canopy sensor will provide more useful high-resolution information than that in a high-resolution EC_a survey.  相似文献   

Conspecific negative density dependence in a long-lived conifer,yew <Emphasis Type="Italic">Taxus baccata</Emphasis> L.     

John L. Devaney  Pádraig M. Whelan  Marcel A. K. Jansen 《European Journal of Forest Research》2018,137(1):69-78

Conspecific negative density dependence in tree species can have major consequences for structuring of communities, yet in temperate forests this phenomenon remains largely unexplored. We investigated density-dependent recruitment in the long-lived conifer yew (Taxus baccata L.), for which low levels of regeneration have been linked with reduced light availability beneath conspecific canopies and speculative autotoxic effects. We combined in situ assessment of yew regeneration in a temperate forest in southwest Ireland with ex situ pot experiments to assess whether light and/or beneath conspecific canopy conditions inhibit the germination and early growth of yew. In field experiments, recruitment was related to distance from adult conspecifics, with higher levels of regeneration found in areas not beneath yew canopies. However, reduced light availability beneath the dense yew canopy was not responsible for this pattern, with abundant seedlings found in areas of equivalent or even lower light availability. Pot experiments showed that seedling survival was highest in deep shade treatments. Experiments also demonstrated that the addition of yew needles negatively affected seedling growth, but not seed germination. Together, our results suggest that under natural forest conditions, the absence of regeneration beneath mature yew canopies, often attributed to low light availability, may at least be partly related to substances in yew canopy or leaf leachates.  相似文献   

Staggers in horses grazing paspalum infected with Claviceps paspali     

AJ Cawdell-Smith  CJ Scrivener  WL Bryden 《Australian veterinary journal》2010,88(10):393-395

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Repeat tuberculin skin testing leads to desensitisation in naturally infected tuberculous cattle which is associated with elevated interleukin-10 and decreased interleukin-1 beta responses     

Michael Coad  Derek Clifford  Shelley G. Rhodes  R. Glyn Hewinson  H. Martin Vordermeier    Adam O. Whelan 《Veterinary research》2010,41(2)

The principal surveillance tool used to control bovine tuberculosis in cattle is the removal of animals that provide a positive response to the tuberculin skin-test. In this study we performed a longitudinal investigation of the immunological and diagnostic consequences of repeated short-interval skin-tests in cattle naturally infected with Mycobacterium bovis. Tuberculin skin-test positive cattle were subjected to up to four further intradermal comparative cervical skin-tests at approximately 60-day intervals. A significant progressive reduction in the strength of the skin-test was observed after successive tests. In contrast, the magnitude of interferon-γ (IFN-γ) responses was not influenced by repeat skin-testing either transiently around the time of each skin-test or longitudinally following repeated tests. A significant boost in blood interleukin-10 (IL-10) production was observed within 3 days following each skin-test although the magnitude of this boosted response returned to lower levels by day 10 post-test. The application of a novel multiplex assay to simultaneously measure seven cytokines and chemokines also identified that skin-testing resulted in a significant and progressive reduction in antigen specific interleukin-1β (IL-1β) whilst confirming stable IFN-γ and elevated IL-10 responses in the blood. Therefore, we have demonstrated that in cattle naturally infected with M. bovis, repeat short-interval skin-testing can lead to a progressive reduction in skin-test responsiveness which has potential negative consequences for the detection of infected animals with marginal or inconclusive skin-test responses. The desensitising effect is associated with decreased IL-1β and elevated IL-10 responses, but importantly, does not influence antigen specific IFN-γ responses.  相似文献   

Fournier's gangrene in a cat     

Danielle E. Berube  DVM  ; Megan F. Whelan  DVM  DACVECC  ; Kathy C. Tater  DVM  DACVD    Kiko E. Bracker  DVM  DACVECC 《Journal of Veterinary Emergency and Critical Care》2010,20(1):148-154

Objective – To describe the clinical course of a cat diagnosed with Fournier's gangrene.
Case Summary – A 2-year-old castrated male cat was presented to an emergency hospital for evaluation of acute onset of lethargy, mucoid anal discharge, and fever. During hospitalization, with provision of supportive care, an area of necrotizing fasciitis around the prepuce and anus developed and surgical debridement was performed. Severe sepsis developed secondary to the necrotizing fasciitis and the cat was eventually euthanized.
New Information Provided – The purpose of this report is to document the first case of Fournier's gangrene in a cat that presented for mucoid anal discharge, lethargy, and mild ataxia, and to alert emergency clinicians to this disease process. Early detection of the disease with prompt, aggressive supportive care and surgical debridement is necessary for successful treatment.  相似文献   

Vertebrate pest damage to wrapped,baled silage in Ireland     

K. McNamara  P. O'Kiely  J. Whelan  P. D. Forristal  H. Fuller  J. J. Lenehan 《国际虫害防治杂志》2013,59(3):167-172

The scale of damage caused by vertebrates to the plastic wrap on baled silage was evaluated on Irish farms. A survey was conducted on 300 farms representative of farming systems and geographical locations throughout Ireland. The scale of damage was classified as farms with 0%, 1-10%, 11-50% or 51-100% of bales with holes in the plastic wrap caused by birds. The proportion of farms within these four classes with damage caused by birds during the short interval between wrapping and removal from the field to storage was 47%, 37%, 15% and 1% of the total, respectively. Correspondingly, during the subsequent storage prior to feedout, bird damage was 37%, 50%, 12%, and 1%. Similarly, the proportions for damage throughout long-term storage due to cats were 71%, 23%, 6% and 0%, while the incidence of damage caused by rats, dogs and farm livestock was comparatively small. The stored bales were fenced against livestock on 86% of farms, while netting, bale painting and other protection methods were used to discourage damage on 2%, 17% and 9% of farms, respectively. The damage caused by birds was more prevalent on farms where the bales were stored on their curved side rather than their flat end, more than twotiers high and in farmyards rather than in fields. Cats damaged the sides and shoulders of the peripheral bales within bale collections, particularly where wrapped bales were stored in the farmyard.  相似文献   

Intramyocardial haematoma causing right ventricular outflow obstruction after brown snake (Pseudonaja species) envenomation in a dog     

K Kang  CR Sharp  CJ Boyd  K Turner 《Australian veterinary journal》2020,98(9):455-461

A 15-month-old, male neutered Staffordshire Bull Terrier cross was presented to its referring veterinarian collapsed and agonal. He was immediately intubated, manually ventilated, and treatment commenced for presumptive snake envenomation with two vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial). The dog was transferred to a referral hospital intubated. Additional diagnostics performed following arrival at the referral hospital included a urine snake venom detection kit test, which was positive for brown snake immunotype. Three additional vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial) were administered until the dog was extubated and able to stand. Venom-induced consumptive coagulopathy (VICC) was diagnosed based on prolonged clotting times and scleral haemorrhage. Paroxysms of right ventricular outflow tract (RVOT) origin ventricular arrhythmias were treated with lignocaine and sotalol. Four days after presentation, a new-grade IV/VI systolic heart murmur was auscultated, prompting an echocardiogram. An anechoic and compartmentalised mass measuring 43 mm × 19 mm was visualized within the right ventricular wall at the RVOT, immediately adjacent to the pulmonic valve. The mass was causing a RVOT obstruction. Its appearance was suggestive of an intramyocardial haematoma, most likely secondary to VICC. The dog remained cardiovascularly stable, and treatment consisted of supportive care. Recheck echocardiograms at 2 and 7 weeks after discharge revealed progressive improvement of the intramyocardial mass and resolution of the associated heart murmur. Although intramyocardial haematomas are rare, it should be considered as a differential in dogs that develop a newly diagnosed heart murmur and/or cardiac arrhythmia following brown snake envenomation.  相似文献   

The effects of earthworms, botanical diversity and fertiliser type on the vertical distribution of soil nutrients and plant nutrient acquisition     

P. A. Massey  R. E. Creamer  R. P. O. Schulte  M. J. Whelan  K. Ritz 《Biology and Fertility of Soils》2013,49(8):1189-1201

The application of phosphorus (P)-based fertiliser to agricultural soils can result in a skewed vertical distribution of P down the soil profile, since the element tends to accumulate at the soil surface. Such accumulation can have detrimental effects on the environment, as the erosion of surface soil can facilitate the transfer of large quantities of P out of the field into water bodies. Earthworm and plant communities are intricately linked to vertical nutrient distributions in soil, with both communities either facilitating or negating the incorporation of nutrients into the soil matrix. This study aimed to investigate the effect of earthworm presence, plant community structure and fertiliser type to affect the distribution of nutrients in experimental mesocosms; with particular emphasis on the vertical distribution of P. Mesocosms were designed to simulate a soil which has a high P concentration at the surface compared to further down the soil profile. It was hypothesised that the presence of earthworms would facilitate the incorporation of P into the soil matrix and the presence of a more botanically diversity community would assimilate a greater quantity of soil nutrients. After 1 year, mesocosms were deconstructed into five depth ranges, and the distribution of nutrients were modelled and analysed. Results indicated that the presence of earthworms did redistribute soil nutrients from the surface into the matrix beneath. This redistribution was apparent from a reduction in nutrient concentrations in the 0–1 cm depth range. The presence of a more botanically diverse community not only assimilated greater soil nutrient concentrations, but also promoted a less even vertical distribution of soil nutrients, demonstrating the importance of soil biota and plant diversity in the redistribution of soil nutrients.  相似文献   

Recent developments in equine dentistry     

CJ Pearce 《New Zealand veterinary journal》2020,68(3):178-186

ABSTRACT

Equine dentistry is a rapidly developing clinical specialty. It has benefitted from key advances in anatomical and physiological research, development of equipment and instrumentation, utilisation of standing sedation and anaesthesia protocols, a change towards minimally invasive surgical techniques, and the introduction of restorative and endodontic techniques translated from techniques used in human and canine dentistry. Anatomical research has provided further insight into the endodontic system of incisors and cheek teeth and how it changes throughout development with age. Studies of the periodontium have demonstrated a rich vascular supply and repair capacity. Routine dental visits are increasingly being performed utilising sedation and clinical instruments for routine examinations. Equipment has become more efficient, battery-operated and miniaturised giving benefits to both equine dental maintenance work and advanced techniques, assisting the transition to minimally invasive techniques, and the development of endodontic and restorative dentistry. Diagnosis has also benefitted from advances in equipment such as patient-side digital radiography systems, high definition oroscopy, and small diameter flexible fibrescopes that are capable of visualising inside a pulp canal. Dental units combining endodontic high- and low-speed drills, suction and air or water flush are becoming increasingly used and adapted for equine use. Sedative combinations and standing anaesthesia protocols have meant that revisions of traditional techniques, as well as novel techniques, can be performed with almost no requirement for general anaesthesia. Equine dentistry can only continue to advance in this way if there is early identification of dental disease through clinical oral examinations, leading to a system based on prophylaxis, as in human dentistry. This necessitates a change in attitude of the public and industry in general to a proactive approach, with early intervention based on examination and diagnostic findings of practitioners and not necessarily based on the clinical signs displayed by the patient.  相似文献   

SHEEPO A sheep management optimisation package for sheep industry specialists     

M B Whelan  P J Bowman  D H White  C R McLeod 《Australian veterinary journal》1985,62(S1):142-143

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