Table 3.

Examples of studies investigating effects of various types of stress on TA in selected laboratory, farm and companion animals

Species	Agea and sex	Type of studyb	Tissue	Method	Number of subjects	Stress manipulation	Control	Effect of stress on TL	Refs.
Wild house mouse (Mus musculus)	Juvenile females (1–6 months)	Expt	Leukocyte	QPCR	8 trt	Rapid reproduction for 5 m (offspring removed)	Pair of females	↓	55
		Long: 5 months			20 con
Wild house mouse (Mus musculus)	Juvenile females (1–6 months)	Expt	Leukocyte	QPCR	9 trt	Crowding for 5 m (offspring not removed)	Pair of females	↓	55
		Long: 5 months			20 con
Wild house mouse (Mus musculus)	Juvenile males (1–6 months)	Expt	Leukocyte	QPCR	10 trt	Crowding for 5 m (offspring not removed)	Male–female pair (offspring removed)	↓	55
		Long: 5 months			8 con
Wild house mouse (Mus musculus)	Adults (3–12 months)	Expt	Leukocyte	QPCR	24 trt	5× repeated infection with Salmonella enterica	5× oral saline	↓ In males	61
		Long: 8 months			24 con
Laboratory mouse C57BL/6J (Mus musculus)	Adults (12 months)	Expt	Leucocyte (blood and saliva)	QPCR	16 trt	4× repeated cycle of tail suspension, forced swim, foot shock, restraint and sleep deprivation	No stress	↓	36
		Long: 4 weeks			16 con
Laboratory mouse C57BL/6J (Mus musculus)	Adult females (12 months)	Expt	Leucocytes (blood and saliva)	QPCR	8 trt	Daily injection of 30 mg/kg corticosterone	Daily injection of vehicle (oil)	↓	36
		Long: 4 weeks			8 con
Sudanian grass rat (Arvicanthis ansorgei)	Juvenile males (2–3 months)	Expt	Hepatic cells	QPCR	12 trt	Chronic ‘jet lag’ (bi‐weekly peturbations of LD cycle) for 30 days	12:12 hours LD cycle for 30 d	↓	104
		Cross			12 con
African grey parrot (Psittacus erithacus)	Adults (0.75–45 years)	Obs	Erythrocyte	QPCR	26 trt	Socially isolated	Pair‐housed	↓	91
		Cross			19 con
Domestic broiler chicken Ross 308 (Gallus gallus domesticus)	Chicks (7 days)	Expt	Lymphocyte	FISH	8 trt	High stocking density (0.06 m2/bird) for 28 days	Low stocking density (0.1 m2/bird) for 28 days	↓	58
		Cross			8 con
Domestic chicken Single Comb White Leghorn (Gallus gallus domesticus)	Adult females (62 weeks)	Expt	Lymphocyte	FISH	12 trt	High stocking density (0.04 m2/bird) and restricted food for 14 days	Low stocking density (0.1 m2/bird) and ad lib. food for 14 days	↓	105
		Cross/long: 14 days			12 con
European starling (Sturnus vulgaris)	Chicks (3 days)	Expt	Erythrocyte	QPCR	11 trt	Cross‐fostered into broods of seven chicks	Cross‐fostered into broods of two chicks	↓	59
		Long: 11 days			12 con
European starling (Sturnus vulgaris)	Chicks (2 days)	Expt	Erythrocyte	QPCR	17 trt	Cross‐fostered to be 4.8 g lighter than competitor chicks in brood	Cross‐fostered to be 4.9 g heavier than competitor chicks	↓	60
		Long: 9 days			18 con
Great reed warbler (Acrocephalus arundinaceus)	Juvenile birds	Expt	Erythrocyte	QPCR	12 trt	Acute and chronic infection with Plasmodium ashfordi	No infection	↓	106
		Long: 9–10 weeks			4 con
Zebra finch (Taeniopygia guttata)	Chicks (1–3 days)	Expt	Erythrocyte	QPCR	30 trt	Brood sizes enlarged by two chicks	No change in brood size	↓	57
		Long: 20 days			25 con
Coho salmon (Oncorynchus kisutch)	Adults (conception)	Expt	Pelic fin (blood and tissue)	QPCR	23 trt	Transgenic fish with enhanced growth rate	Wild‐type	↓	99
		Long: 10 months			15 con

Expt, experimental; Obs, observational/correlational; long, longitudinal; cross, cross‐sectional; QPCR, quantitative PCR; FISH, fluorescence in situ hybridisation; trt, treatment; con, control; ↓ indicates shorter telomeres (cross‐sectional studies) or greater attrition (longitudinal studies) in stress manipulation group relative to control group.

^aFor longitudinal studies, age is the age of the subjects at the start of the stress manipulation.

^bDurations given for longitudinal studies refer to the period between the first and second telomere measurements.