PHYSICAL EXAMINATION AND DIAGNOSTICS
1.1 Ophthalmology
The macropscopic and histological ocular anatomy of Lumholtz’s tree kangaroos (Dendrolagus Iumholtzi) has been described (Shima et al. 2020).
Ophthalmic findings in healthy red kangaroos (Osphranter rufus) and western grey kangaroos (Macropus fuliginosus) are outlined in Table 31.1 (Labelle et al.
2010b; Takle et al. 2010).Electroretinographic values were measured in six healthy zoo-housed anaesthetised western grey kangaroos (Labelle et al. 2010a). Assessment of retinal electrical function has a range of applications including the detection of ocular lesions associated with hypertension (see section 4.2.3a). Additional information on macropod ophthalmic anatomy and physiology can be found in Vogelnest and Portas (2008).
1.2 Clinical pathology
Haematological and biochemical data have been reported for free-ranging and managed macropod populations (see Appendix 1).
Activated partial thromboplastin time (aPTT) of rednecked wallabies (Notamacropus rufogriseus), measured using a point-of-care analyser (Abaxis VSPro®), was found to be comparable to dogs and cats (Nevitt et al. 2016; see Appendix 1). Prothrombin time (PT) was significantly longer; the authors speculated whether this was a true representation of PT in red-necked wallabies, or that the method was inappropriate for this species. Alternate reagents and analytical methods should be investigated.
Measures of antioxidant capacity (trolox equivalent antioxidant capacity [TEAC], and ferric reducing antioxidant power [FRAP]) and a measure of lipid oxidation (thiobarbituric acid reducing substances [TBARS]) were serially examined in brush-tailed rock-wallabies (Petrogale penicillata) during a reintroduction program (Schultz
Table 31.1. Ophthalmic findings reported in healthy zoo-housed red kangaroos (Osphranterrufus) and western grey kangaroos (Macropus fuliginosus)
| Mean ± SD | Mean ± SD or mean (25-75% range) | |
| Species | Red kangaroo (Osphranterrufus; n = 10)1 | Western grey kangaroo (Macropus fuliginosus; n = 8)2 |
| Restraint | Physical | Medetomidine, ketamine and isoflurane |
| Ophthalmoscopy | ||
| Iris | Uniformly brown in colour | Uniformly brown in colour |
| Pupil | Round | |
| Fundic reflection | Red to orange in colour | |
| Fundus | Medium brown to red in colour, no tapetum lucidum, myelinated round optic disc | No tapetum lucidum, round pale-pink optic disc with myelin radiations |
| Corneal diameter | 19.52 ± 2.16 mm | |
| Schirmer tear test | 22.6 ± 6.07 mm (ventral fornix, 60 sec) | |
| Intraocular pressure | ||
| Applanation tonometry | 22.12 ± 8.68 mmHg (≤3 yr) 14.33 ± 3.99 mmHg (>3 yr) | 11.5 (10.0-17.0) mmHg |
| Rebound tonometry | 9.0 (6.5-10.75) mmHg | |
| Pupillary mydriasis | ||
| Pre-topical tropicamide | 12.72 ± 1.13 mm | |
| Post-topical tropicamide | 15.89 ± 1.28 mm | |
| Onset of mydriasis | 16.7 ± 3.34 min | |
| Duration of mydriasis | 17.6 ± 8.26 hr | |
| Conjunctival flora | Predominantly gram-positive | |
1Takle etal. 2010; 2Labelle etal.
2010bet al. 2011). The oxidative stress index (OSI) (the ratio of TBARS to the sum of TEAC and FRAP, with values <1 indicating a level of antioxidant capacity sufficient to mitigate peroxidative damage) was calculated as an indicator of nutritional and metabolic stress. Compared with animals in managed care, TBARS and OSI values were higher in hardening-off exclosures and in the wild; however, mean OSI remained <1. Antioxidant measures in free-ranging and managed black-footed rock wallabies (P. lateralis) were reported by Ruykys et al. (2012). These measures can provide an indication of how well an animal is coping in the face of potentially adverse events (e.g. translocation, disease, hospitalisation) and complement other indicators of stress (see Chapter 8).
1.3 Diagnostic imaging
The ultrasonographic appearance of abdominal organs and a systematic approach for qualitative and quantitative abdominal ultrasonographic evaluation of juvenile eastern grey kangaroos (Macropus giganteus) have been reported (Barkman et al. 2023).
2.