Effect of Temperature on and Histopathology of the Interaction Between Meloidogyne incognita and Thielaviopsis basicola on Cotton

ABSTRACT Controlled environments were used to study the relationship between the root-knot nematode (Meloidogyne incognita) and Thielaviopsis basicola on cotton. Temperature treatments were continuous 20, 24, and 28 degrees C or two cyclic linear regimes with ranges of 14 to 32 or 18 to 28 degrees C over 24 h. Cotton seeds were planted in fumigated soil infested with T. basicola, M. incognita, or both. After 42 days, pathogen effects on plant growth and pathogen development were evaluated. Histology was conducted on roots collected 14, 28, and 42 days after planting in the continuous 24 degrees C treatment. Reductions in plant height-to-node ratio and total fresh weight were observed for soils infested with both pathogens compared with the control or with soils infested with either pathogen, except for M. incognita-infested soil at 28 degrees C. T. basicola reduced root galling and reproduction of the nematode at all temperatures. Vascular discoloration caused by T. basicola was greater in the presence of M. incognita compared with that by T. basicola alone. At 2 and 4 weeks, histological studies showed that plants grown in all T. basicola-infested soils contained chlamydospore chains on the root surface and in cortical cells. The fungus was not observed inside the vascular cylinder. Roots from 4-week-old plants from soils infested with T. basicola and M. incognita showed fungal sporulation in vascular tissue and localized necrosis of vascular tissue adjacent to the nematodes. At 6 weeks, plants grown in soil infested with T. basicola alone exhibited no remaining cortical tissue and no evidence of vascular colonization by the fungus. Six-week-old plants grown in T. basicola + M. incognita-infested soils exhibited extensive vascular necrosis and sporulation within vascular tissue. These studies suggest that coinfection expands the temperature ranges at which the pathogens are able to cause plant damage. Further, M. incognita greatly increases the access of T. basicola to vascular tissue.     

Use of praziquantel for treatment of Diphyllobothrium sp infection in a dog

Eggs of a tapeworm, Diphyllobothrium sp (probably D dendriticum), were detected in feces of a healthy, 5-month-old, Siberian Husky. The dog acquired its infection in northern Canada while consuming a diet that included raw salmonid fish. Such fish serve as intermediate hosts for Diphyllobothrium spp. The infection was successfully eliminated by oral administration of a single dose of praziquantel (7.5 mg/kg of body weight.     

Intraventricular tension pneumocephalus as a complication of transfrontal craniectomy: a case report

OBJECTIVE: To report the diagnosis and surgical treatment of a case of intraventricular tension pneumocephalus in a dog after a transfrontal craniectomy for removal of a falx cerebri meningioma. STUDY DESIGN: Case report. ANIMAL: A 12-year-old spayed English springer spaniel. RESULTS: Intraventricular air and a fistula between the craniectomy site and ventricular system were identified by magnetic resonance imaging. Prompt repair of the dural defect using prosthetic dura mater resulted in immediate regression of the neurological signs and cerebral spinal fluid rhinorrhea. Magnetic resonance imaging repeated 8 weeks after surgery showed complete resolution of pneumocephalus. CONCLUSIONS AND CLINICAL RELEVANCE: Tension pneumocephalus is an uncommon but life-threatening complication of craniectomy that requires urgent diagnosis and treatment.     

Frequency and seasonal distribution of pear psylla infected with the pear decline phytoplasma in california pear orchards

ABSTRACT Pear decline (PD) is an important disease of Pyrus communis fruiting cultivars in Europe, Asia, and the Americas. PD is caused by a phloem-limited phytoplasma that, in California, is transmitted from diseased to healthy trees by pear psylla, Cacopsylla pyricola. The percentage of phytoplasma-infected pear psylla has never been assessed in the United States in field-collected insects. Pear psylla were collected monthly from PD-infected trees from three orchards in northern California. Individual psylla were tested for the presence of PD phytoplasma, using both a quantitative DNA hybridization and PD phytoplasma-specific polymerase chain reaction (PCR) assays. The percentage of infected psylla ranged from 0 to 45% depending on the orchard, the month and year collected, and the method of detection. The PD phytoplasma was detected in both the winterform and summerform pear psylla. Significantly more infected psylla were detected with PCR than with DNA hybridization analysis in two of the three orchards. The number of PD phytoplasma per pear psylla was estimated to range from 1 x 10(6) to 8.2 x 10(7). The percentage of PD-infected pear psylla found in the three northern California pear orchards suggests that both winterform and summerform pear psylla could be important in the transmission of PD.     

A comparison of Freund's Complete and Freund's Modified Adjuvants used with a contraceptive vaccine in wild horses (Equus caballus).

Fifteen captive wild mares (Equus caballus) were treated with porcine zona pellucida contraceptive vaccine and either Freund's Complete Adjuvant (n = 7) or Freund's Modified Adjuvant (n = 8). All mares received a booster inoculation of porcine zona pellucida plus Freund's Incomplete Adjuvant a month later. Anti-porcine zona pellucida antibodies were measured over 10 mo following the initial inoculation. There were no significant differences in antibody titers at any point during the 10 mo, and seven of the eight mares in the Freund's Modified Adjuvant group were above the 60% level at the end of the study, which is considered to be the contraceptive threshold for horses. There were no significant differences in titers between pregnant and nonpregnant horses, nor was there a significant correlation between age and titers. One local injection site reaction occurred after booster treatment with Freund's Incomplete Adjuvant, and 11 healthy foals were born during the course of the study. These data suggest that Freund's Modified Adjuvant is an acceptable substitute for Freund's Complete Adjuvant in certain free-ranging and captive wildlife species.     

Ultrasonographic Characteristics of Ovulatory Follicles and Associated Endocrine Changes in Cyclic Ewes Treated with Medroxyprogesterone Acetate (MAP)-releasing Intravaginal Sponges and Equine Chorionic Gonadotropin (eCG)

The aim of this study was to assess the ultrasonographic characteristics of ovulatory follicles in cyclic Western White Face ewes (December) that had received intravaginal sponges containing medroxyprogesterone acetate (MAP; 60 mg) for 12 days, with or without an injection of 500 IU of equine chorionic gonadotropin (eCG) at sponge removal. We hypothesized that quantitative echotextural attributes of the follicles in ewes treated only with MAP would differ from those in MAP/eCG-treated ewes, reflecting the increased antral follicular growth and secretory function under eCG influence. Digital images of ovulatory follicles obtained at 0 and 24 h after MAP sponge removal and at 24 h before ovulation in the eCG-treated (five ewes, 13 follicles) and control (six ewes, 9 follicles) animals, were subjected to computerized analyses. The mean diameter of ovulatory follicles increased (p < 0.001) 24 h after eCG treatment. The mean pixel intensity and heterogeneity of the follicular antrum (p < 0.001), as well as mean pixel intensity of the follicular wall and perifollicular ovarian stroma (p < 0.05), were greater in eCG-treated animals compared with control ewes 24 h after sponge removal and at 24 h before ovulation. Mean serum concentrations of oestradiol-17beta tended to increase (p = 0.06) 24 h after eCG treatment and the eCG-treated ewes exceeded (p < 0.05) control animals in progesterone concentrations from days 9-15 after ovulation. Our results support the hypothesis that large antral follicles in eCG-treated ewes exhibit distinctive echotextural characteristics. Follicular image attributes in eCG-treated ewes appear to be indicative of the changes in follicular morphology and secretory activity caused by the administration of the exogenous gonadotropin, which has both FSH- and LH-like activities.     

Implementing immunocontraception in free-ranging African elephants at Makalali conservancy

The goal of programmes to provide contraception for elephants should be to formulate an approach that does not require the relocation or immobilisation of the same individual year after year, which would be long-lasting and cause minimal disruption to social and reproductive behaviour. The programmes should be simple to administer, safe and cost-effective, and must meet the objectives defined by managers in the field. An immunocontraceptive programme was initiated in a small free-roaming population of elephants at the Greater Makalali Private Game Reserve in Limpopo Province in 2000 to determine whether the porcine zona pellucida (pZP) vaccine can successfully control population sizes. Further objectives were to determine implementation costs and efficiency through a multi-faceted approach. We have demonstrated that immunocontraception meets the objectives set by managers in the field. Minimal social disruption was observed over the course of treatment, with the mode of delivery (ground or aerial vaccinations) determining the degree of stress within herds and speed of resumption of normal movement patterns. Aerial vaccinations resulted in the least disturbance, with target herds being approachable within a day. In 2005, implementation costs were R880-R1000/elephant/year, inclusive of darts, vaccine, helicopter and veterinary assistance. Irrespective of the source or method of vaccine delivery, a non-pregnant elephant is rendered infertile from 1st vaccine administration. The sooner immunocontraception is implemented, the sooner population growth rates can be controlled. pZP contraception is a realistic alternative management tool, particularly if used as part of a long-term management strategy. Mass-darting from the air eliminates the need for detailed individual histories of each elephant or for employing a person to monitor elephants. Thus, implementation of immunocontraception in larger populations is feasible and practical.     

Saltmarsh conservation through inventory,biogeographic analysis and predictions of change: Case of Tasmania,south‐eastern Australia

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