Table 2.

Summary of included studies.

Author	Strain	Sex	Age at Intervention	Animals per Group	Study Design	Intervention	Accompanying Conditions	Frequency of Intervention (Occasions)	Comparator	Outcome
Aasland et al. 2010 [22]	C57BL/6JBomTac	M	NR	n = 8	RCT (crossover)	Saphenous vein Tail vein	N/A	4 by both methods at 2 weeks apart	Each other Time series	Plasma glucose Hemolysis
Abatan et al. 2008 [9]	ICR	F	NR	n = 8–13 (unclear from methods)	RCT	Saphenous vein Tail tip amputation	N/A	One-off collection Serial sample at 2–3 day intervals (4)	Each other Time series	Plasma corticosterone Behaviours noted during blood collection
Christensen et al. 2009 [23]	C57BL/6JBom	M	NR	n = 20	RCT	All sample methods were performed at 21 and 30 °C, i.e., 8 experimental groups Retrobulbar Tail incision Tail tip amputation Tail tip puncture	N/A	Serial sample at 30 min intervals (4)	Other groups	Blood glucose Haemolysis Clotting
Durschlag et al. 1996 [24]	ICR	M	9 weeks	n = 8	Case report	Tail incision	N/A	Serial sample at 2–3 day intervals (5)	Time series	Histology Plasma corticosterone
Fernandez et al. 2009 [25]	C57BL/6J	M	6 weeks	n = 10	RCT (crossover)	Retrobulbar Facial vein	Anaesthesia (retrobulbar)	Serial sample at 6–8 week intervals (3)	Each other	Blood glucose Haemolysis
Forbes et al. 2010 [26]	Balb/c	F	6–8 weeks	n = 214	Retrospective case series	Facial vein	Lancet or needle for sampling	Serial sample at 2–7 day intervals (6)	Nil	Mortality
Francisco et al. 2015 [27]	BALB/c	F	5 weeks	n = 20	RCT	Facial vein (lancet or needle)	Facial vein route with anaesthesia as one group	One-off collection	Other groups	Adverse events Gross post-mortem site evaluation
Fried et al. 2015 [28]	C57BL/6N background with a mutation in MDA5	M/F	4–6 months	n = 8	RCT	Retrobulbar	Anaesthesia	One-off collection	Time series at 0, 1, 3, 7 or 14 days after sampling	Clinical scores Histology
Frolich et al. 2018 [29]	C57BL/6NCrl	F	12–14 weeks	n = 12	RCT	Retrobulbar Facial vein	Anaesthesia (retrobulbar)	One-off collection Serial sample at 1 wk intervals (6)	Each otherSingle versus serial	Adverse events Mortality Bodyweight Histology Plasma glucose
Gjendal et al. 2020 [30]	C57BL/6	F	10 weeks	n = 30	RCT	Retrobulbar Facial vein Sublingual	Anaesthesia (retrobulbar) Facial vein and sublingual anaesthesia groups, in addition to conscious sampling	Serial sample at days 8, 9, and 10 (short protocol) and days 8, 15, and 22 (long protocol)	Eachother Single versus serial	Nest build score Faecal corticosteroid metabolites Bodyweight Haemolysis Clotting Gross post-mortem site evaluation
Harikrishnan et al. 2018 [12]	C57BL/6NTac	M/F	6 weeks	n = 12	RCT	Retrobulbar Sublingual Facial vein Tail incision	Anaesthesia (retrobulbar)	Serial sample at 24 h interval (2)	Other groups, plus isoflurane control, and behavioural test control (naïve animals)	Nest build score Elevated plus maze Open field test Faecal corticosteroid metabolites
Heimann et al. 2009 [4]	Crl: CD-1 [CR]	M/F	11 weeks	n = 30	RCT	Sublingual Retrobulbar	Anaesthesia	One-off collection	Each other	Histology
Heimann et al. 2010 [1]	CD1	F	14 weeks	n = 18	RCT	Sublingual Facial vein	Anaesthesia (for sublingual and one facial vein group)	One-off collection	Other groups, time series at 3 h, two or five days after sampling	Bodyweight Food intake Histology Blood glucose
Kim et al. 2018 [10]	CD-1 C57BL/6	M	NR	n = 4–6	RCT	Retrobulbar Tail tip amputation	Anaesthesia (retrobulbar) Restrain/unrestrained	One-off collection Serial sample tail tip groups at 30 min intervals (5)	Other groupsTime series	Plasma corticosterone
Madetoja et al. 2009 [31]	Hsdwin:NMRI	F	9 weeks	n = 10	RCT	Saphenous vein Facial vein Tail vein	Tail warming heat lamp	One-off collection	Other groups, and control with no blood samples	Plasma corticosterone Plasma ACTH
Moore et al. 2017 [32]	C57BL/6J	M	10–12 weeks	n = 8–12	RCT	Facial vein Tail tip amputation Tail incision	N/A	One-off collection	Other groups, and sham submandibular and tail tip amputation (just restraint)	Blood glucose Audible vocalisations Post-procedural epochs of inactivity Grooming behaviour Nest build score Elevated plus maze Open field test Histology
Regan et al. 2016 [33]	CD1	F	12–13 weeks	n = 15	RCT	Retrobulbar Facial vein Submental	Anaesthesia (retrobulbar)	Serial sample at 2 week intervals (3)	Other groups	Adverse events Bodyweight Extraneous blood loss Gross post-mortem site evaluation Haemolysis Clotting
Rogers et al. 1999 [34]	Study 1 (single sample) C57BL/6	F	10–12 weeks	n = 72	RCT (crossover)	Retrobulbar	Thermostatic warming chamber	One-off collection (each method)	Each other	Plasma glucose
	Study 2 (repeated sample) C57BL/6	F	10–12 weeks	n = 48		Tail incision		Serial sample at 1 week interval (2)		Plasma insulin
Sadler et al. 2013 [7]	Study 1 (single sample) BALB/CAnNCrl Study 2 (repeated sample) BALB/CAnNCrl	M M	7–8 weeks 3–4 weeks	n = 5 n = 4/5	RCT	Tail incision Tail vein Tail incision	Thermostatic warming chamber Tail dipped hot water	One-off collection Serial sample at 24 h intervals (3)	Other groups Time series	Plasma corticosterone
Shirasaki et al. 2012 [35]	ICR C57BL/6N	M	6 weeks	n = 10 (unclear from methods)	RCT	Jugular Tail incision	N/A	One-off collection Serial sample at 24 h intervals (5)	Each other Time series	Plasma CRP Plasma corticosterone Plasma haemoglobin Hematocrit Plasma thrombin–antithrombin complexes
Sorenson et al. 2019 [36]	C57BL/6NTac	F	8 weeks	n = 36	RCT	Retrobulbar Saphenous Sublingual Facial vein Tail incision Tail tip amputation	Anaesthesia (retrobulbar)	One-off collection	Each other, plus isoflurane control and naïve animals (no bleeding) Time series at nine timepoints: 6 or 10 h or 1, 2, 4, 6, 8, 10, or 12 days after sampling	Bodyweight Stomach contents Plasma corticosterone Inflammatory gene expression at sample site Plasma inflammatory markers (haptoglobin and IL1ß) Histology
Tabata et al. 1998 [37]	Study 1 (single sample) B6C3Fl/ICR Study 2 (repeated sample) B6C3Fl	M/F M/F	8 weeks 9 weeks	n = 12 n = 20	RCT	Tail tip amputation	Tube restraint or anaesthetized with ether or pentobarbital §	One-off collection Serial sample at varied intervals for 24 h (8)	Other groups Time series	Plasma glucose
Teilmann et al. 2014a [2]	BomTac:NMRI	M	6–8 weeks	n = 8–18	RCT	Facial vein Tail vein	N/A	Two day and two night samples within 24 h (4)	Other groups, plus controls (no blood sample and naïve animals as behavioural control)	Bodyweight Plasma corticosterone Faecal corticosteroid metabolites Triple test (elevated plus maze, open field test, light–dark box)
Teilmann et al. 2014 [38]	C57BL/6J	M	5 months	n = 8–12	RCT	Retrobulbar Facial vein	N/A	One-off collection	Other group, plus control (no blood sample)	Bodyweight Plasma corticosterone Histology
Tsai et al. 2015 [8]	BALB/cO1aHsd	F	8 weeks	n = 12	RCT	Jugular Retrobulbar (with and without anaesthesia) Saphenous Facial vein Tail vein	Anaesthesia (retrobulbar group and jugular)	One-off collection	Other groups	In-cage activity Plasma corticosterone Open field test Histology
Tuli et al. 1995 [11]	Study 1 (acute stress) BALB/c/Ola Study 2 (tail bleeding recovery) BALB/c/Ola	M M	5–6 months 5–6 months	n = 5 n = 5	RCT	Tail tip amputation	Tail dipped hot water	One-off collection each route Serial humane killing at day 2, 4 and 8 after blood sample	Other groups and control with no tail amputation	Plasma corticosterone Adrenal weight Spleen weight
Voigt et al. 2013 [13]	C57BL/6CrlN	F	4–6 months	n = 36 (16 contributed to final results due to technical failure)	RCT (crossover)	Blood-sucking bug Retrobulbar Tail incision	Anaesthesia (retrobulbar)	One-off collection each route (note crossover design)	Other groups	Faecal corticosteroid metabolites

NR—not reported. ^§—The aim of this section of the study was to investigate common scenarios, such as anaesthesia, which elevated blood glucose in laboratory mice, rather than investigate the blood sampling technique per se. The reviewers still considered the study was worthy of inclusion since it could provide data on the topic but have only extracted data relevant to the review question. Note: Restraint not included as an accompanying condition unless effects of this specifically investigated as part of study design, since this would be needed for all sample routes.