I Dr. Philemon Kipkemoi Towett went through primary, secondary and university educations in Kenya where I attained the following certificates:  Kenya certificate of Primary Education (KCE), Kenya Certificate of Secondary Education (KCSE), Kenya Advanced Certificate Education (KACE), Bachelor of Veterinary Medicine (BVM), Master of Science in Comparative Mammalian Physiology (MSc.) and Doctor of Philosophy in Comparative Animal Physiology (Ph. D).




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Makau, CM, Towett PK, Abelson KSP, Kanui TI.  2021.  Modulation of nociception by amitriptyline hydrochloride in the Speke’s hinge‐back tortoise (Kiniskys spekii). Veterinary Medicine and Science. early view AbstractWebsite

Background: There are limited studies on the utilization of analgesics in testudines.
Management of pain in reptiles is by use of analgesics generally used in other vertebrate species. Evidently, some analgesics considered to be generally effective in
reptiles are not effective in certain reptile species.
Objective: The purpose of this study was to examine the effect of amitriptyline hydrochloride on nociceptive behaviour in Speke's hinge-back tortoise.
Methods: Twenty-four adult Speke-hinged tortoises weighing 500–700 g were used.
The effects of amitriptyline hydrochloride on nociception were evaluated using the
formalin, capsaicin and hot plate nociceptive tests. Amitriptyline was administered
intracoelomically at doses of 0.5, 1.0 and 3.0 mg/kg.
Results: The higher doses of amitriptyline hydrochloride caused an increase in nociceptive behaviour (time spent in hindlimb withdrawal) on the formalin and capsaicin
nociceptive tests, suggesting a potentiating effect. However, the doses used had no
significant change in nociceptive behaviour on withdrawal response in the hot plate
Conclusions: The study showed that amitriptyline hydrochloride which is widely used
in management of neuropathic pain potentiates nociceptive effects in the formalin
and capsaicin nociceptive tests in the Speke's hinge-back tortoise. The hot plate test,
which previously has not been reported in these animals, gave results not in line
with the other tests and therefore more testing and validation of the test is required.
Amitriptyline modulates chemical and thermal pain differently


C.M., M, Towett PK, Abelson KSP, Kanui TI.  2017.  Modulation of formalin-induced pain-related behaviour by clonidine and yohimbine in the Speke’s hinged tortoise ( Kiniskys spekii ). .Journal of Veterinary Pharmacology and Therapeutics. 40(5):439-446. AbstractWebsite

The study was designed to investigate the involvement of noradrenergic and serotonergic receptor systems in the modulation of formalin-induced pain-related behaviour in the Speke's hinged tortoise. Intradermal injection of 100 μL of formalin at a dilution of 12.5% caused pain-related behaviour (hindlimb withdrawal) that lasted for a mean time of 19.28 min (monophasic response). Intrathecal administration of clonidine (α2-adrenergic receptor agonist) and yohimbine (α2-adrenergic receptor antagonist) at a dose of 40 μg/kg and 37.5 μg/kg or 50 μg/kg, respectively, caused a highly significant reduction in the duration of the formalin-induced pain-related behaviour. The effect of clonidine was reversed by intrathecal administration of yohimbine at a dose of 26.7 μg/kg. The effect of yohimbine at a dose of 50 μg/kg was reversed by intrathecal injection of 20 μg/kg of the serotonergic receptor antagonist methysergide maleate. When performing antagonistic reactions, the administration of the antagonist was followed immediately by that of the agonist. The study indicates that for experimental purposes, intrathecal route of drug administration through the atlanto-occipital joint is effective in tortoises. The data also suggest that testudines have noradrenergic and serotonergic systems that appear to play a role in the modulation of pain in this species.


Makau, CM, Towett PK, Abelson KSP, Kanui TI.  2014.  Intrathecal administration of clonidine or yohimbine decreases the nociceptive behaviour caused by formalin injection in the mash terrapin (Pelomedusa subrufa).. Brain and Behaviour. 4(6):850-857. Abstract

Background: The role of noradrenergic system in the control of nociception is
documented in some vertebrate animals. However, there are no data showing
the role of this system on nociception in the marsh terrapins. Methodology: In
this study, the antinociceptive action of intrathecal administration of the a2-
adrenoreceptor agonist clonidine and a2-adrenoreceptor antagonist yohimbine
was evaluated in the African marsh terrapin using the formalin test. The interaction of clonidine and yohimbine was also evaluated. Results: Intrathecal
administration of clonidine (37.5 or 65 lg/kg) caused a significant reduction in
the mean time spent in pain-related behavior. Yohimbine, at a dose of 25 lg/kg,
significantly blocked the effect of clonidine (65 lg/kg). However, administration
of yohimbine (40 or 53 lg/kg) caused a significant reduction in the mean time
spent in pain-related behavior. Intrathecal administration of yohimbine (53 lg/
kg) followed immediately by intrathecal injection of the serotonergic methysergide maleate (20 lg/kg) resulted in a significant reversal of the antinociceptive
effect of yohimbine. Conclusion: The present study documented the intrathecal
administration of drugs in the marsh terrapin, a technique that can be applied
in future studies on these animals. The data also suggest the involvement of
both a2-adrenoreceptors and 5HT receptors in the modulation of nociception
in testudines.

Dulu T.D, kanui T.I., P.K. T, G.M. M, K.S. A.  2014.  The effects of oxotremorine, epibatidine, atropine, mecamylamine and naloxone in the tail flick, hot plate, and formalin tests in the naked mole rat (Heterocephalus glaber). In vivo. 28(1):39-48. AbstractWebsite

Abstract. The naked mole-rat (Heterocephalus glaber) is a
promising animal model for the study of pain mechanisms,
therefore a thorough characterization of this species is
essential. The aim of the present study was to establish the
naked mole-rat as a model for studying the cholinergic
receptor system in antinociception by investigating the
involvement of muscarinic, nicotinic and opioid receptors in
nociceptive tests in this species. The effects of systemic
administration of the muscarinic receptor agonist
oxotremorine and the nicotinic receptor agonist epibatidine
were investigated in the tail-flick, the hot-plate, and the
formalin tests. The effects of co-administration of the
muscarinic receptor antagonist atropine, the nicotinic
receptor antagonist mecamylamine, and the opioid receptor
antagonist naloxone were also investigated. Oxotremorine
and epibatidine induced a significant, dose-dependent
antinociceptive effect in the tail-flick, hot-plate, and formalin
tests, respectively. The effects of oxotremorine and
epibatidine were blocked by atropine and mecamylamine,
respectively. In all three nociceptive tests, naloxone in
combination with oxotremorine or epibatidine enhanced the
antinociceptive effects of the drugs. The present study
demonstrated that stimulation of muscarinic and nicotinic
receptors produces antinociceptive effects in the naked-mole
rat. The reversal effect of atropine and mecamylamine
suggests that this effect is mediated by cholinergic receptors.
As naloxone increases the antinociceptive effects of
cholinergic agonists, it is suggested that the cholinergic
antinociception acts via a gateway facilitated by opioid
receptor blockage; however, the precise interaction between
these receptor systems needs further investigation.


N, WS, KIPKEMOI TOWETPHILEMON, SG K, KSP A, TI K.  2009.  Effects of Opioids in the Formalin Test in the Speke’s Hinged Tortoise (Kinixys spekii).. Journal of Veterinary Pharmacology and Therapeutics. 33(4):347-351.: VLIR AbstractWebsite

Little is known about analgesia in lower vertebrates such as the Speke’s hinged tortoise (Kinixy’s spekii), yet of late they are increasingly being adopted as pets. The effects of morphine (5, 7.5, 10 and 20 mg/kg), pethidine (10, 20, and 50 mg/kg) and naloxone (5 mg/kg) on nociception induced by the formalin test (12.5%, 100 μL) were studied in the Speke’s hinged tortoise. Formalin induced a monophasic limb retraction behavioural response and its duration was recorded. The behaviour lasted for 16.4 ± 0.8 min. Morphine (7.5, 10 and 20 mg/kg) and pethidine (20 and 50 mg/kg) induced significant decrease in the duration of limb retraction in the formalin test. The anti‐nociceptive effects were naloxone (5 mg/kg) reversible. The data suggest that the formalin test is a good test for studying nociception and anti‐nociception in tortoises and that the opioidergic system plays a role in the control of nociception in these animals.


Maloiy, GMO, Kanui TI, P.K. T, Wambugu SN, J.O. M, M.M. W.  2008.  Effects dehydration and heat stress on food intake and dry matter digestibility in east African ruminants.. Comparative Biochemistry and Physiology, Part A.. 151(2):185-190.: 2008 Abstractpubmed

Comparative investigations were made between wild and domestic ruminants from arid and semi-arid regions and those species from non-arid areas in an attempt to evaluate the adaptations of these ruminants in terms of the effects of heat stress and dehydration on food intake and digestibility. The effect of (a) an intermittent heat load (a daily light cycle of 12 hat 22 "C and 12 hat 40 'C) compared to 22 'C throughout the day and (b) dehydration level of 15% weight loss, with and without the heat load, on the intake and digestibility of a poor quality hay was investigated in the Grant's gazelle, Oryx, the domestic Turkana goats, fat-tailed sheep, zebu cattle, Thomson's gazelle and wildebeest The intermittent heat load with water available ad libitum depressed the food intake of zebu cattle and Turkana goats by more than 40%. It had no significant effect on the food intake of the other species. The Thomson's and Grants gazelle, oryx, wildebeest and fat-tailed sheep appear well adapted to withstanding a periodic heat load. Dehydration at 22 'C caused a marked depression on food intake of all the species investigated. Dehydration together with a heat load caused no further reduction in the food intake by the Grants's gazelle, oryx, and goats but it did cause a further reduction in the intake in the other species. The small non-domestic ruminants (i.e. Grant's and Thomson's gazelle) appear much more digestive efficient than any of their domestic counterpart.

Towett, PK, Kanui TI, Ole Maloiy GM, Juma F, Ole Miaron JO.  2008.  Activation of mu, delta or kappa opioid receptors by DAMGO, DPDPE, U-50488 or U-69593 respectively causes antinociception in the formalin test in the naked mole-rat (Heterocephalus glaber. Pharmacology Biochemistry and Behavior. 91(4):566-572. Abstract

Data available on the role of the opioid systems of the naked mole-rat in nociception is scanty and unique compared to that of other rodents. In the current study, the effect of DAMGO, DPDPE and U-50488 and U-69593 on formalin-induced (20 μl,10%) nociception were investigated. Nociceptive-like behaviors were quantified by scoring in blocks of 5 min the total amount of time (s) the animal spent scratching/biting the injected pawin the early (0–5 min) and in the late (25–60 min) phase of the test. In both the early and late phases, administration of 1 or 5 mg/kg of DAMGO or DPDPE caused a naloxone-attenuated decrease in the mean scratching/biting time. U-50488 and U-69593 at all the doses tested did not significantly change the mean scratching/biting time in the early phase. However, in the late phase U-50488 or U-69593 at the highest doses tested (1 or 5 mg/kg or 0.025 or 0.05 mg/kg, respectively) caused a statistically significant and naloxone-attenuated decrease in the mean scratching/biting time. The data showed that mu, delta or kappa-selective opioids causes antinociception in the formalin test in this rodent, adding novel information on the role of opioid systems of the animal on pain regulation.

KIPKEMOI, DRTOWETPHILEMON.  2008.  Wambugu, S.N., Kanui, T.I., Towett, P.K., Kiama, S.G., Abelson, K. The formalin test and capsaicin instillation in the Marsh Terrapin (Pelomedusa subrufa). In the 5th International Congress of the African Association of Physiological Sciences (AAPS), 2008. : 2008 Abstract

Samples of burnt clay from kilns in various parts of the country were tested for their cementatious qualities and found to have high silica contents.Results showed that additing upto 40% of the cly to portland cement produced good binders for mass concre and plaster work,particularly for low cost housing.


KIPKEMOI, DRTOWETPHILEMON.  2007.  Wambugu, S.N., Joakim, D., Towett, P.K., Kiama, S.G. and Kanui, T.I. Laboratory management of captive hingeback tortoises. Workshop on Reptile Care, Health and Welfare, 2007. Presented at the Commonwealth Association of Surveying and Land Economy (CASLE) and the International Federation of Surveyors (FIG) Seminar, Harare,. : 2008 Abstract
Samples of burnt clay from kilns in various parts of the country were tested for their cementatious qualities and found to have high silica contents.Results showed that additing upto 40% of the cly to portland cement produced good binders for mass concre and plaster work,particularly for low cost housing.


KIPKEMOI, TOWETPHILEMON.  2006.  Stimulation of mu and delta opioid receptors induces hyperalgesia while stimulation of kappa receptors induces antinociception in the hot-plate test in the naked mole-rat (Heterocephalus glaber). . Brain Research Bulletin. 71:60-68.: 2008 AbstractScienceDirect

The antinociceptive effects of highly selective mu (DAMGO), delta (DPDPE) and kappa (U-50488 and U-69593) opioid agonists were evaluated following intraperitoneal (i.p.) administration in the naked mole-rat. A hot plate test set at 60 °C was used as a nociceptive test and the latency to the stamping of the right hind paw (response latency) was used as the end-point. DAMGO (5–10 mg/kg) and DPDPE (2.5–5 mg/kg) caused a naloxone-reversible significant decrease in the mean response latency. Subcutaneous injection of naloxonazine (20 mg/kg) 24 h prior to the administration of DAMGO (5 mg/kg) also blocked the reduction in the response latency observed when DAMGO was injected alone. On the contrary, U-50488 (2.5–5 mg/kg) or U-69593 (0.08 or 0.1 mg/kg) caused a naloxone-reversible significant increase in the mean response latency. These results showed that activation of mu or delta receptors caused hyperalgesia, whereas activation of kappa receptors caused antinociception in the hot plate test in naked mole-rat. This suggests that mu and delta receptors modulate thermal pain in a different way than kappa receptors in the naked mole-rat. It is not possible at the moment to point out how they modulate thermal pain as little is known about the neuropharmacology of the naked mole-rat.


KIPKEMOI, TOWETTPHILEMON, IKUSYA KANUITITUS.  1995.  Hyperlgesia following administration of morphine and pethidine in the root rat (Tachoryctes splendens).. Journal of Veterinary Pharmacology and therapeutics 18 (1995) 68. 18(1):68-71.: 2008Wiley online Library


KIPKEMOI, TOWETTPHILEMON, Kanui TI.  1993.   Effects of Pethidine, Acetylsalicylic acid and Indomethacin on pain and behaviour in the naked mole-rat.. Pharmacology Biochemistry and Behaviour . 45:153-159.: 2008 AbstractScienceDirect

The antinociceptive and behavioral effects of pethidine (10, 20, or 30 mg/kg), acetylsalicylic acid (200, 400, or 600 mg/kg) and indomethacin (20, 40, or 50 mg/kg) in the naked mole-rat was studied in the hot-plate test. Instead of inducing analgesia, pethidine caused a dose-dependent reduction in response latency. Sensorimotor impairment and aggressive behavior were also observed following administration of pethidine (20 or 30 mg/kg). All animals recieving pethidine (30 mg/kg) died following fighting when kept in colony cages. Aggressive behavior and death was prevented by naloxone or by keeping animals in single cages. Acetylsalicylic acid (600 mg/kg) and indomethacin (40 or 50 mg/kg) caused a significant increase in response latency. It is concluded that in the mole-rat pethidine elicits aggression, sensorimotor impairment, and apparent hypergesia.

TI, K, F K, KIPKEMOI TOWETPHILEMON.  1993.  The formalin test in the naked mole-rat (Heterocephalus glaber): Analgesic effects of morphine, nefopam and paracetamol.. Brain Research. 600(1):123-126.: 2008 AbstractScience Direct

The present experiments were initiated to study the effects of morphine, nefopam and paracetamol in the naked mole-rat, a hairless rodent that lives in subterranean colonies of up to 300, following the inability to demonstrate morphine analgesia in the hot-plate test in the rodent. The formalin test was used. Injection of 20 microliters 10% formalin produced two periods of high licking and pain behaviour, the early (0-5 min) and the late phase (15-60 min). Morphine (10 or 20 mg/kg), nefopam (10 or 20 mg/kg) and paracetamol (200 mg/kg) significantly inhibited the two phases. Paracetamol (400 mg/kg) produced significant analgesia only during the late phase. It is concluded that, unlike in the hot-plate test, it is possible to demonstrate the analgesic effects of morphine in the naked mole-rat, in the formalin test.

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