Non-invasive hormone monitoring as a robust method for determining adrenocortical activity in injured, emaciated and oil-contaminated African penguins undergoing rehabilitation.

Anthropogenic activity is a major driver of seabird injury and mortality in the 21st century. Although most seabirds perish within the natural environment as a result of human activities, some are rescued and admitted to rehabilitation centres. Despite the considerable number of admissions, little is known regarding the physiological response seabirds have to specific admission reasons and the rehabilitation process. In this study, we aimed to determine the effect of injury, emaciation, oiling, individual removal from the natural environment and the rehabilitation process on the physiological stress response of the African penguin (Spheniscus demersus). Urofaecal samples were collected from African penguins throughout a three-stage rehabilitation process and quantified for glucocorticoid metabolites (ufGCM). The three stages included an initial ICU crate stage (Stage 1), an ICU pen stage (Stage 2) and a rehabilitation stage (Stage 3). Data were analysed using a generalised linear model in order to determine the effect of admission reason, age and rehabilitation stage (Stage 1, 2 and 3) on ufGCM levels. Although the model indicated that only Stage 1 was a significant driver of adrenocortical activity in the study population, ufGCM levels of injured and emaciated animals within Stage 1 were considerably higher than those of birds with any other admission reason across all stages. This is the first study examining the causes and effect of rehabilitation on the physiological stress response in African penguins. Enhanced care and attention should be given to rescued individuals, especially during the first stage of rehabilitation, to reduce perception of additional stressors and thus increase the chance of full recovery.

South African legislation for radiation control in dentistry: a review.

The objective of this study is to provide South African dentists with a sound knowledge of radiation safety together with accepted policy and some recommendations to protect individuals who may be exposed to ionizing radiation from dental X-ray equipment. The Directorate of Radiation Control of the Department of Health of South Africa was approached to provide information pertaining to radiation control in dentistry. The material was reviewed and applicable information, together with literature on radiation control in other countries, is summarized.

Design of an x-ray room for a dental practice.

Radiography is one of the most valuable diagnostic tools used in comprehensive dental care. Although it is generally accepted that there is no safe level of radiation exposure, the possible risk involved with exposure to X-rays must be weighed against the benefits of clinical interpretation. One important step in limiting the risk of radiation exposure at the workplace is the correct design of an X-ray room. A dentist or dental therapist, who is the license holder of the radiation equipment, is ultimately responsible for the radiation safety at the workplace. The aim of this article is to provide dental practitioners with guidelines and recommendations on X-ray room designs in order to facilitate radiation control and safe working conditions for radiation workers as well as the public.

The possible role of Ostertagia circumcincta, coccidiosis and dietary protein level in the development of swelling disease in Angora goat kids.

A trial was carried out to investigate the possible role of Ostertagia circumcincta, coccidiosis and level of protein in the diet in the development of swelling disease in Angora goat kids. Eighty Angora goat kids were bought from 5 producers whose flocks had a history of swelling disease. These kids were kept in enclosures at Grootfontein Agricultural Development Institute near Middelburg (Eastern Cape) for the duration of the experiment. The animals received a combination of the following treatments: (a) high protein vs normal protein diet; (b) Ostertagia circumcincta infection or no O. circumcincta infection; (c) coccidial infection or no coccidial infection. Data recorded included weekly body weight, weekly total plasma protein levels (TPP), weekly faecal egg counts, weekly coccidial oocyst counts and haematology at Weeks 1, 5, 9, 13 and 16. The goats were also monitored daily for any clinical symptoms. There was no specific trend in any of the parameters measured among the different treatment groups at any stage during the experimental period. The goats were shorn during Week 10 of the experiment. On Monday 6 September 2004 (Week 12 of the study), 19 of the goats developed some subcutaneous oedema. The Saturday (4 September 2004) was rather hot (30 degrees C), followed by very cold rainy conditions (11 degrees C) on Sunday (5 September 2004). Twelve of the goats developed what can be described as little oedema, while 7 developed moderate oedema. The number of goats that developed oedema was fairly evenly distributed among the various treatment groups. As far as the specific treatments are concerned, more goats on the normal protein diet developed moderate oedema than the goats on the high protein diet. Body weights of goats that developed moderate oedema were lower throughout the experimental period than body weights of goats that developed little or no oedema, while TPP of goats that developed moderate oedema were lower from Week 5 of the study onwards. There were also no significant differences at any stage throughout the experimental period in faecal egg counts, faecal coccidial oocyst counts or any of the blood parameters between goats that developed moderate oedema, little oedema and those that did not develop any oedema. No goats developed full-blown swelling disease during the course of the experiment. It is possible that the treatments applied in this study are not inductive of the disease, or the effects of the treatments were not severe enough to induce swelling disease.

The effect of water intake prior to blood sampling on packed cell volume in sheep.

The effect of water intake prior to blood sampling on subsequent packed cell volume (PCV) was investigated in ewe lambs (8 months of age) of the Dohne Merino, Merino and Letelle flocks at Grootfontein Agricultural Development Institute. On the afternoon of the day before the experiment was conducted, a blood sample for a baseline PCV value (R) was taken from each animal. The following day, 15 ewes of each breed (n = 45) were dosed with 1 litre of water and another 15 of each (n = 45) were used as a control. Blood samples for PCV were taken concurrently for both the control and water treatment groups before the dose (0), and at 15, 30 and 60 minutes after dosing. PCV were subsequently determined with the microcapillary centrifuge technique. Baseline PCV of Letelle ewes was higher (32.4 +/- 0.6) than that of the Dohne Merino (29.7 +/- 0.6) and Merino (28.7 +/- 0.6) ewes. Furthermore, recovery rate at 30 minutes after treatment also differed among breeds. Although there were significant differences between the control and water treatment groups at R and 0 minutes, which were probably due to inherent animal differences, there were no significant differences between PCV of the 2 groups during the remainder of the experimental period. Overall it can be concluded that water intake before blood sampling for the determination of PCV has no significant effect on haematocrit. Differences among breeds were more pronounced than those between treatment groups.

Control of Karoo paralysis ticks through vegetation management.

Karoo paralysis, caused by feeding Ixodes rubicundus females, is a major disease of small stock in South Africa. Control methods currently practised are almost exclusively chemical based. To limit overdependance on chemicals, vegetation management was investigated as a possible method for control, to be incorporated in an integrated tick management system. Laboratory and field experiments were conducted to determine, firstly, the extent of vertical migration and survival of ticks on long and short copper rods which simulated grasses as questing substrates; secondly, the infestation burdens of sheep exposed to similar tick challenges in pens with long and short grass; and thirdly, the effect of trimming the lower crown line of wild olive trees, simulating the browsing effect of goats, on tick density in the immediate environment of the trees. When ticks were exposed to optimal ( > 45 cm) and sub-optimal ( < 10 cm) length rods on which to quest, the extent of vertical migration over extended periods of time (up to 87 days) was significantly higher (P < 0.001) for the ticks exposed to long rods. Also, almost 3 times as many ticks exposed to long rods survived compared to those exposed to short rods. Sheep exposed to long grass were infested by twice as many ticks compared to those exposed to short grass. Tick density at modified wild olive trees (Olea europaea africana) (0.027 ticks/m2) differed significantly (P < 0.05) from that at control trees (0.088 ticks/m2). It is recommended that coarse grazers such as cattle and horses should be used to graze down long grasses before sheep are introduced into camps known to be infested with I. rubicundus. Similarly, domestic goats can, through their browsing effect on shrubs and trees, modify the vegetation and as such play an important role in an integrated tick management system.

Vertical migration of adult Ixodes rubicundus, the Karoo paralysis tick (Acari: Ixodidae).

Mortality due to Karoo paralysis amongst livestock is of considerable economic importance in South Africa. Indications are that the extent of vertical migration of adult ticks, to reach questing positions on grasses, is influenced by sudden climatic changes. Such influences as well as selection of questing substrates were investigated under controlled conditions. Vertical migration of adult Ixodes rubicundus on copper rods was determined in a square metal arena within a closed glass container in a room in which temperature and light could be controlled. Significantly more female and male ticks migrated vertically on 1.5 mm diameter rods than on 4.0 mm rods and on 450 mm long rods than on 100 mm rods. More ticks of both sexes migrated vertically at RH > 80% than at RH < 50% and at 12 degrees C than at 21 degrees C. More female than male and more older than younger ticks migrated vertically in all experiments. The results of this study contribute towards an understanding of the epidemiology of Karoo paralysis.

The appetence behaviour of two South African paralysis-inducing ixodid ticks.

The appetence responses of the ixodid ticks Ixodes rubicundus and Rhipicephalus punctatus to various stimuli were quantified under laboratory conditions. A greater percentage of I. rubicundus generally responded to the different stimuli at lower than at higher temperatures while the converse was usually true for R. punctatus. Radiation heat and shadowing evoked a response in the greatest percentage of I. rubicundus, whereas CO2 and host odour were responsible for a similar reaction in R. punctatus. A single perturbation of the substrate caused more than 50% of I. rubicundus to respond while constant perturbation resulted in a progressive decrease in the proportion of ticks reacting. Significantly more R. punctatus than I. rubicundus were attracted to a CO2 trap and the R. punctatus were also attracted to the trap over a greater distance. Significantly more older than younger ticks of both species responded to the various stimuli.

Assessing malnutrition in gastric carcinoma: bioelectrical impedance or clinical impression?

The value of bioelectrical impedance (BI) as an index of body composition was assessed in 32 patients with gastric carcinoma, 20 with advanced disease. Bioelectrical impedance was compared with standard nutritional parameters: weight, body mass index (BMI), albumin, transferrin and triceps skinfold thickness. There was no correlation between BI and these parameters with the exception of weight and BMI in the male patients. Clinical assessment of nutrition on the other hand correlated well with the standard parameters. Although BI may be a useful adjunct to the routine assessment of nutritional status in normal subjects, its use in clinical patients should be treated with caution, particularly in those with advanced gastrointestinal malignancy.