The effect of undernutrition on haematological and serum biochemical variables in wild boar (Sus scrofa)

Trap-effectiveness and response to tiletamine-zolazepam and medetomidine anaesthesia in Eurasian wild boar captured with cage and corral traps

Background

Capture, handling and chemical restraint are basic techniques often needed for research or management purposes. The aim of this study was testing a combination of tiletamine-zolazepam (TZ) (3 mg/kg) and medetomidine (M) (0.05 mg/kg) on Eurasian wild boar (Sus scrofa). A total of 77 free-ranging wild boar were captured by means of portable cages and corral traps and then anaesthetized with intramuscular darts using a blowpipe. The individual response to chemical immobilization was characterized using anaesthetic, clinical, and serum biochemical variables. After the procedure, 14 of these wild boar were monitored for 20 days using GPS-GSM collars.

Results

Pre-release mortality during capture and handling (6.5%) was associated with severe trauma in corral traps. Capture specificity for wild boar was 96.3% and trapping effort was 16.5 days per captured wild boar. Mean induction period was 4.5 ± 2.2 min, hypnosis period enabling effective handling was 61.6 ± 25.4 min, and recovery period was 12.8 ± 12.1 min. No heart or respiratory failure due to added stress occurred and post-release monitoring by GPS-devices revealed no mortality due to anaesthesia. According to the best statistical model obtained, the main factor driving anaesthetic efficacy and stress indicators is trap type.

Conclusions

Both cage and corral traps are efficient methods to capture wild boar. Cage traps are safer, as demonstrated by mortality rates as well as anaesthetic, physiological, and serum biochemical responses. This anaesthetic protocol is useful for prolonged handling of wild boar and allows sampling and collecting data for ecological and epidemiological studies.

Haematology and serum chemistry of Pyrenean chamois (Rupicapra pyrenaica) naturally infected with a border disease virus

In 2005 and 2006 an outbreak of disease associated with border disease virus (BDV) infection caused high mortality in the Pyrenean chamois (Rupicapra pyrenaica) in the Catalan Pyrenees (NE Spain). The aim of this study was to determine values for different haematological and serum biochemical analytes in 32 free-ranging Pyrenean chamois affected by the disease and to compare them with those obtained from healthy chamois. In the affected chamois red blood cell counts, haemoglobin concentrations, packed cell volumes, mean corpuscular volumes and lymphocyte counts were all lower, while the neutrophil and platelet counts were higher. Glucose, lactate, triglycerides, creatinine, total protein concentrations and alkaline phosphatase activity were also lower, in contrast to the concentrations of total bilirubin, urea and aspartate aminotransferase activity, which were higher. Most of the observed changes could be associated with cachexia and inflammation in the affected chamois. Lymphopenia could be directly related to the BDV, which would lead to immunosuppression and explain the high rate of secondary infection observed in these animals.

Effects of parasitic helminths and ivermectin treatment on clinical parameters in the European wild boar (Sus scrofa)

Limited information exists on serum biochemistry and haematology of the European wild boar, and few correlations have been found between parasitic burden and clinical parameters in this species. Naturally infected wild boars were experimentally treated to study the effect of nematode parasites and ivermectin treatment on phytohaemagglutinin (PHA) skin reaction and haematological and serum biochemical parameters. White blood cells decreased in untreated wild boars, whereas triglyceride, lactate and creatinine concentrations increased in ivermectin-treated wild boars, and total protein and aspartate aminotransferase activity increased in both groups. Band neutrophils variation was positively correlated with the number of total adult parasites. Band neutrophils, creatinine and total protein variations were negatively correlated with both total egg counts and Metastrongylus eggs per gram variations. Alkaline phosphatase activity showed a negative correlation with Ascaris sp. eggs. The PHA skin reaction was positively correlated with the number of total adult parasites in untreated wild boars and with Metastrongylus sp. eggs of all wild boars at time 0. Two models including leukocytic and serum biochemical parameters were also highly correlated with the variation of Metastrongylus sp. eggs. Clinical parameters were thus in our study affected by helminth parasitism in the European wild boar, particularly those related to nutrients uptake, physical condition and immune response. Therefore, they could be useful in studies on subclinical effects of parasites, and parasitic burden must be considered when assessing the physical condition of European wild boars through haematological and serum biochemical parameters.

Temporal, population, and sexual variation in hematocrit of free-living desert tortoises: correlational tests of causal hypotheses

Hematocrit (packed cell volume, PCV) varies seasonally in some vertebrates and often differs between the sexes and among conspecific populations. Such variation in PCV may reflect variation in nutritional health, requirements for oxygen transport (metabolic rate), or hydration. The relative importance of these influences was tested with serial measurements of PCV in two Mojave Desert populations of the desert tortoise (Gopherus agassizii) over two activity seasons, during a period with large seasonal differences in availability of food and water. Hematocrit varied widely (range = 14–40, CV = 20%), reflecting differences between populations, between sexes, between years, and over time within years. Causal hypotheses were tested by correlating PCV with physiological indicators of nutritional health (blood urea nitrogen), oxygen requirements (field metabolic rate), and hydration (length-relative mass, water-influx rate, urine osmolality, plasma sodium, and plasma osmolality). Results indicated a dominant influence of dehydration-induced hemoconcentration during this extreme drought period, although all correlations were relatively weak. Circumstantial evidence is marshalled to suggest longer term effects of nutrition (at seasonal, yearly, and population levels of variation) and perhaps oxygen requirements (driving sexual dimorphism). All these simultaneous and sometimes opposing effects interact in complex ways to produce the patterns of variation observed, and these interactions render PCV a poor indicator of physiological state in desert tortoises.