Successful treatment of a squamous cell carcinoma in a white rhinoceros, Ceratotherium simum

A captive 33-year-old male white rhinoceros with seasonal dermatitis was diagnosed with a malignant squamous cell carcinoma on the right flank. Staphylococcus aureus was cultured from the skin lesions. No fungal or yeast was isolated. The dermatitis was treated with a combination of oral antibiotics (trimethoprim-sulphadiazine) and topically with weekly chlorhexidine washes and a mixture of a zinc oxide, balsam peru and bismuth oxide cream. Under azaperone and butorphanol anaesthesia, the skin tumour was surgically removed. The tumour was excised with wide margins and allowed to heal by secondary intention as primary wound closure was not possible. A post-mortem performed 2 years later for an unrelated condition revealed no metastases or recurrence of the skin tumour. It was presumed that chronic irritation or trauma may have contributed to the development of the skin tumour. This is the first detailed report of the successful treatment of a squamous cell carcinoma not associated with the horn in a rhinoceros.     

Cardiovascular effects of acute pulmonary obstruction in horses with recurrent airway obstruction

BACKGROUND: Recurrent airway obstruction (RAO) is common in horses. Although pulmonary artery (PA) pressure increases during RAO, cardiac function in horses with RAO has received limited attention. HYPOTHESIS: The purpose of this study was to noninvasively determine the cardiovascular effects of acute pulmonary obstruction (APO) in horses with RAO and their reversibility. ANIMALS: Five geldings with RAO, inducible by exposure to moldy hay, were studied. METHODS: Pulmonary mechanics, echocardiography, serum troponin I concentrations, arterial blood gases, and hematocrit were obtained before and after 7 days of APO. Heart rate, PA diameter and flow characteristics, right and left ventricular luminal dimensions and wall thicknesses, global cardiac performance, and evidence of myocardial damage were evaluated. Pulmonary mechanics and echocardiography were reevaluated during remission. RRESULTS: Severe, transient APO did not induce chronic cor pulmonale in horses, because cardiac anatomy and function were normal between episodes. An acute episode of APO produced anatomical and functional cardiac changes in both the right and left heart (including increased PA diameter, abnormal septal motion, and decreased left ventricular diameter and estimated stroke volume), possibly because of the development of pulmonary hypertension, without apparent myocardial damage. The decrease in stroke volume was offset by the increase in heart rate. CONCLUSIONS AND CLINICAL IMPORTANCE: With APO of 7 days' duration, cardiovascular abnormalities and the functional airway changes that produce them are reversible when the offending allergens are removed.     

Optimising cutting method and timing for the control of Abutilon theophrasti seed production

Abutilon theophrasti (velvetleaf) is a widespread and problematic annual weed. Greenhouse and field experiments were conducted to investigate the effects of different cutting methods on the viability of A. theophrasti seeds. Three cutting methods were assessed: (1) Entire plant cut and dried (EPD)—plants were cut at soil level and dried with capsules attached on the greenhouse bench or soil surface for 4 weeks; (2) capsules detached and dried (CD)—capsules were removed from plants and dried for 4 weeks; and (3) capsules detached and tested while fresh (CF)—a control treatment. Before drying, the developmental stage (stage one, dark green; stage two, light green; stage three, yellowish-green; or stage four, black with the slightly open capsule) and age (days after flowering, DAF) of each capsule was recorded. Seed viability was measured immediately in the CF treatment and after the 4-week drying period in the EPD and CD treatments. No seeds in the EPD and CD treatments were viable when harvested at the first developmental stage (1–8 DAF) in either experiment, but 100% of seeds in the CF treatment in the field were viable when harvested at 8 DAF. In both greenhouse and field experiments, seeds attained full viability at earlier harvest ages in CF than in EPD or CD treatments, suggesting that seeds might become viable relatively early in development but lose viability if allowed to dry. These findings could be applied to optimise late-season mechanical control of A. theophrasti.     

Changes in the herbicide sensitivity and competitive ability of Abutilon theophrasti over 28 years: Implications for hormesis and weed evolution

BACKGROUND

The potential of weed species to respond to selection forces affecting the evolution of weedy traits such as competitive ability is poorly understood. This research characterized evolutionary growth changes in a single Abutilon theophrasti Medik. population comparing multiple generations collected from 1988 to 2016. A competition study was performed to understand changes in competitive ability, and a herbicide dose–response study was carried out to assess changes in sensitivity to acetolactate synthase-inhibiting herbicides and glyphosate over time.

RESULTS

When grown in monoculture, A. theophrasti biomass production per plant increased steadily across year-lines while leaf number decreased. In replacement experiments, A. theophrasti plants from newer year-lines were more competitive and produced more biomass and leaf area than the oldest year-line. No clear differences in sensitivity to imazamox were observed among year-lines. However, starting in 1995, this A. theophrasti population exhibited a progressive increase in growth in response to a sublethal dose of glyphosate (52 g a.e. ha⁻¹), with the 2009 and 2016 year-lines having more than 50% higher biomass than the nontreated control.

CONCLUSION

This study demonstrates that weeds can rapidly evolve increased competitive ability. Furthermore, the results indicate the possibility of changes in glyphosate hormesis over time. These results highlight the importance of the role that rapid (i.e., subdecadal) evolution of growth traits might have on the sustainability of weed management strategies. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Tick-borne encephalitis epidemic in Hungary 1951–2021: The story and lessons learned

The authors analysed epidemiological data of the Hungarian tick-borne encephalitis epidemic from the past seven decades. A total of 911 meningitis serosa cases were described from 1930-1950 s by local hospital physicians, indicating that the virus had been present in the country decades before its official identification in 1952. The virus spread freely in the 1950s–1960s, occupying almost all habitats where ticks occurred in large numbers. The increasing number of cases drove authorities to classify this illness as a notifiable disease in 1977 and to organize the first measures to stop the epidemic. Statistical analysis revealed that the large-scale vaccination launched from the 1990s was responsible for the sharp decrease in the number of human cases from 1997. A significant negative correlation was found between the number of vaccine doses sold and human cases 6 years later. The TBEV endemic area covers 16.57% of the territory and 16.65% of the population of the country. In the last 10 years, 186,000 vaccine doses/year in average were enough to keep the incidence of human TBEV infections between 0.45 and 0.06/100,000 persons. A 20-year-long study found evidence for easing clinical signs in TBEV-infected hospitalized patients. Statistics found a sharp decrease in the number of samples sent for TBEV diagnosis after 1989. Male dominance of patients was characteristic of the epidemics since the 1940s, but now analysis of detailed data from the 1981–2021 period (60.5%–87.5%) proved the statistical significance of this dominance. Obviously, the voluntary vaccination programme was the tool which broke the spread of the epidemic. Widespread public awareness of the disease and the tick vector, probable evolutionary spread of less pathogenic virus strains supplemented with the vaccination campaign led to a negligible level of human TBE cases in Hungary in the last years.     

Effects of beta-aminopropionitrile on equine tendon metabolism in vitro and on effects of insulin-like growth factor-I on matrix production by equine tenocytes

OBJECTIVE: To investigate effects of beta-aminopropionitrile and a combination of insulin-like growth factor (IGF)-I and beta-aminopropionitrile on metabolism of equine tendon fibroblasts. SAMPLE POPULATION: Flexor tendon explants from 3 horses. PROCEDURE: Explants received 1 of 4 treatments (control, IGF-I, beta-aminopropionitrile, and IGF-I/beta-aminopropionitrile) for 10 days, and message expression for collagen types I and III was assessed by use of in situ hybridization. Histologic findings, new protein production, and quantitative determinations of glycosaminoglycan, DNA, and de novo collagen synthesis were made. RESULTS: Insulin-like growth factor-I stimulated an anabolic response in tendon. Collagen synthesis and glycosaminoglycan and DNA content of explants were all increased. Beta-aminopropionitrile significantly suppressed collagen synthesis, which was not ameliorated by concurrent IGF-I treatment. Beta-aminopropionitrile caused alterations in cell morphology characterized by large round cells with eccentric nuclei and decreased density of collagen fibers. Protein production and collagen type-III mRNA expression were reduced in these cells. CONCLUSIONS AND CLINICAL RELEVANCE: Treatment with beta-aminopropionitrile resulted in decreased production of protein and collagen synthesis, which could be expected to suppress tendon healing. The negative effects of beta-aminopropionitrile could not be abrogated by addition of IGF-I to the medium. Treatment resulted in alterations in cell morphology and matrix consistency, which could further delay tendon healing. Beta-aminopropionitrile may impair tendon healing at a cellular level by decreasing collagen production or increasing rate of degradation of existing matrix. Because of reduced crosslinking during beta-aminopropionitrile treatment, in combination with transiently decreased tensile strength, alterations in collagen content and structure may weaken the healing tendon.     

Possible involvement of salicylic acid in systemic acquired resistance ofCucumis sativus againstSphaerotheca fuliginea

The possible involvement of salicylic acid in systemic acquired resistance ofCucumis sativus againstSphaerotheca fuliginea was studied. Cucumber plants were inoculated with tobacco necrosis virus on the cotyledons and the level of endogenous salicylic acid in the first true leaf was determined by gas chromatography. Salicylic acid increased continously from the second day after virus inoculation to the fifth day, when the same leaf was inoculated withSphaerotheca fuliginea. In healthy plants, the efficiency of exogenous salicylic acid in inducing resistance was assayed by applying aqueous solutions at different times beforeSphaerotheca fuliginea inoculation. To evaluate the level of induced resistance, the following parameters were examined by light microscopy: percentage of conidial germination, length of the hyphae derived from single conidia, number of haustoria, percentage of epidermal cells with lignified walls and of necrotic cells underlying fungal hyphae. In treated plants conidial germination was reduced, the total length of the hyphae was shorter, the number of haustoria was lower and the haustorium-containing epidermal cells had more frequently lignified walls. Moreover, an evident increase in callose deposition was observed leading to the formation of oversized papillae around the penetration pegs. These results indicate that the application of salicylic acid before inoculation withSphaerotheca fuliginea reduces the intensity of the infectious process and that salicylic acid is involved in the expression of systemic resistance in cucumber challenged by the biotrophic pathogenSphaerotheca fuliginea.