Livestock Research for Rural Development 28 (8) 2016 Guide for preparation of papers LRRD Newsletter

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Thermogram of naturally helminth-infected Galea spixii treated with aqueous extract of garlic (Allium sativum)

Joăo Paulo Araújo Fernandes de Queiroz, Joăo Batista Freire de Souza Jr, Vanessa Raquel de Morais Oliveira, Claudionor Antonio dos Santos Filho, Ana Carla Diógenes Suassuna Bezerra, Moacir de Oliveira Franco, Leonardo Lelis de Macedo Costa and Alex Martins Varela de Arruda

Department of Animal Science, University of Federal Rural of Semiarid, 572 Francisco Mota Avenue, Costa e Silva, 59625-900 Mossoró-RN, Brazil


This study aimed to detect changes in the thermal profile of naturally helminth-infected Spix’s yellow-toothed cavies treated with aqueous garlic extract. Fifteen non-pregnant mature females were randomly divided into three groups, with five animals per group. Parasitological examinations revealed moderate infection by Ancylostomidae for all groups at the beginning of the trial. One group was treated with a single dose of an anthelmintic solution. The other two groups were treated with 500μl of aqueous garlic extract at concentration of 30 and 60 mg/ml. Microclimatic conditions were continuously monitored while infrared thermal images were being taken by a thermographyc camera.

The high-concentration garlic extract was more effective in controlling Ancylostomidae infection. Surface temperature of the cavies did not change in response to different infection levels.

Key words: Ancylostomidae, infrared thermography, Spix’s yellow-toothed cavy, thermal environment


The Spix’s yellow-toothed cavy (Galea spixii) is a neotropical hystricognathi rodent illegally hunted and held captive in northeastern Brazil for human consumption. Its slaughter in the consumer’s domicile exposes humans, domestic animals, and the environment to biological contaminants such as pathogenic parasites. The public health risk is aggravated by the lack of knowledge about abundance, composition, and zoonotic potential of the parasitic fauna of Galea spixii. Understanding the host-parasite relationships allows to refine the sanitary management and to improve animal welfare in legalized breeding. The breeding of wild rodents follows no specific protocols for prophylaxis and treatment of helminthic infections. It usually follows the recommendations for domestic rodents and lagomorphs, such as guinea pigs and rabbits, respectively. Plant-based medicines have been used by pet tutors, livestock farmers and professionals as part of the endoparasite control program. This ethno-veterinary practice is an alternative to allopathic drugs, safe for animals and the environment, and inexpensive. One of the most used botanical species for this purpose is garlic (Allium sativum). This plant has antitumor, anti-inflammatory, antifungal, antibacterial, antiprotozoa, and anthelmintic activities (Balasenthil et al 2002; Dkil et al 2011; Lanzotti et al 2012; Riad et al 2013; Moghadam et al 2014; Khalil et al 2015) as well as many other biological effects. Its anthelmintic properties have been reported in fish, chicken, mice, rat, cattle, sheep, and goat (Amin et al 2008; Burke et al 2009; Velkers et al 2011; Peni et al 2012; Riad et al 2013; Fridman et al 2014).

Monitoring of the body temperature during infectious processes allows to assess the parasite's pathogenicity and the treatment progress. Infrared thermal imaging is a remote, accurate, and non-invasive method which quantifies infrared radiation emitted by a surface. This technology provides valuable information about thermoregulatory responses and health status of the animals (Speakman and Ward 1998; McCafferty 2007; Tattersall and Cadena 2010). However, careful microclimatic monitoring is needed to help understand if the changes in the body surface temperature are usual responses to the thermal environment or associated with the disease condition. Thus, this study aimed to detect changes in the thermal profile of naturally helminth-infected cavies treated with aqueous garlic extract.

Materials and methods


The procedures were previously authorized by the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA) through the Chico Mendes Institute for Biological Conservation (ICMBio), number 49262-1.

Study location

The study was carried out at the Multiplication Center of Wild Animals (5°11'15'' South, 37°20'39'' West, approximately 16 m altitude) of the Federal Rural University of Semiarid (UFERSA), municipality of Mossoró, State of Rio Grande do Norte, Brazil. The region is within the Caatinga’s biogeographic domain, an exclusively Brazilian biome. The climate is semiarid hot and dry (BSh type), according to the climatic classification of Köppen-Geiger.

Animals, housing, and management

The animal model was the Spix’s yellow-toothed cavy (Galea spixii Wagler, 1831). Fifteen non-pregnant mature females were randomly divided into three groups, with five animals per group. Cavies were housed in enriched enclosures measuring 2.5 × 3.0 × 3.8 m (length × width × height) with solarium, dirt floor, and shelters simulating burrows. The walls were fitted with a shortwall (0.4 m height) and smooth wire mesh. Maize grains, commercial feed for adult rabbits, and vegetables were provided daily in tray feeders. Fresh water was freely available from drinker bottles with aluminium nozzles. Enclosures were cleaned daily to avoid soil recontamination from feces.

The main contact animals in captivity were agoutis (Dasyprocta leporina Linnaeus, 1758), collared peccaries (Pecari tajacu Linnaeus, 1758), and greater rheas (Rhea americana Linnaeus, 1758). A large number of wild species of free-living birds inhabited the study area. The presence of brown rats, goats, sheep, and non-domiciled dogs and cats was notified.

Aqueous garlic extract

The aqueous garlic extract (AGE) was prepared by homogenizing fresh garlic in distilled water until the required concentration was reached. The homogenate was centrifuged at 3200 × g for 10 minutes, and the supernatant was frozen until used (Balasenthil et al 2002). The experimental trial lasted seven days (days 0 to 6). Group A was treated with a single dose (0.5 ml per kilogram of body weight) of an anthelmintic solution (fenbendazole 200 mg + pyrantel pamoate 144 mg + praziquantel 50 mg per 5 ml of solution) by oral administration on day one. Groups B (30 mg/ml) and C (60 mg/ml) were treated with 500μl AGE daily by oral administration from day one to five.

Parasitological examinations

Animals were placed in cages with collection trays on day zero. Feces samples were collected from each group and analyzed by a simple sedimentation method (Hoffman et al 1934). The egg counts (n) of gastrointestinal nematodes were performed in a McMaster chamber (Gordon and Whitlock 1939) and results were expressed as number of eggs per gram of feces (n × 50, epg). Nematode infection was classified into three levels based on quantitative egg excretion: mild (<100 epg), moderate (100 to 400 epg), and heavy (>400 epg). These protocols were repeated on days three and six. Images were taken by a high-resolution digital microscope imager (Model 44421, Celestron, California, USA). Egg morphometry was performed using the software Image J 1.49.

Thermal environment

The thermal environment was monitored for atmospheric temperature (TA , °C), wet-bulb temperature (TW, °C), wind speed (U, m s−1), black globe temperature in the sun (TSUN, °C), and black globe temperature in the shade ( TSH, °C) on days zero and six from 09:00 to 09:30 hours. The parameters TA and TW were measured with a digital psycrometer (Model ITHT-2600, Instrutemp, Sao Paulo, SP, Brazil), U by a thermo-anemometer (Model TAFR-190, Instruterm, Sao Paulo, SP, Brazil), and TSUN and TSH with two digital globe thermometers (Model ITWTG-2000, Instrutemp, Sao Paulo, SP, Brazil). All devices were installed inside the enclosure, except the globe thermometer to measure TSUN. Relative humidity (RH, %) was estimated from TA and TW.

Mean radiant temperature (TMR, °C) of the environment was estimated from meteorological data according to Da Silva et al (2010) and applied to calculate the radiant heat load (RHL = σTMR, W m−2). The TMR is the mean temperature of all real and virtual surfaces that compose the environment and RHL is the amount of radiant energy present in a system in which there is heat exchange between the animal and its environment (Da Silva and Maia 2013).

Surface and body core temperature

Rectal temperature (TR , °C) was used for predicting body core temperature. Surface temperature (TS, °C) and rectal temperature were measured on days zero and six from 09:00 to 09:30 hours. TS was recorded by an infrared thermal imaging camera (Model Flir b60, FLIR® Systems Inc., Oregon, USA; ˗20 to 120 °C temperature range, ± 2% accuracy, 0.07°C thermal sensitivity) set to an emissivity of 0.98. In the composition of the thermal profile we considered the following regions: ocular surface, auricular surface (considering auricular pavilion and external ear), and body surface. Thermal images were analyzed using the software ThermaCAM Researcher Pro 2.10 (FLIR® Systems Inc., Oregon, USA). TR wwas measured by a digital clinical thermometer (0.1°C thermal sensitivity).

Statistical analysis

Analysis of variance (ANOVA) for surface temperature, rectal temperature, and meteorological variables was performed by the least-squares method (Da Silva 1993) using the procedure General Linear Models (GLM) of the software Statistical Analysis System (SAS 1999). ANOVA for meteorological variables considered the model

Yij = µ +di + ɛij

where Yij is the jth recording of the meteorological variable on the ith day, μ is the general mean, d is the fixed effect of the ith day (i = 0 and 6), and εij is the residual effect.

ANOVA for surface and rectal temperatures was based on the mathematical model

Yijk = µ + di + tj + Iij +  ɛijk

where Yijk is the kth registration of the physiological variable on the ith day and jth treatment, μ is the general mean, d is the fixed effect of the ith day (i = 0 and 6), t is the fixed effect of the jth treatment (t = A, B and C), I is the nested interaction considering the effect of jth treatment (i.e. infection level) within ith day, and εijk is the residual effect.


We found eggs of the order Strongylida, superfamily Ancylostomatoidea and family Ancylostomidae, at different developmental stages in fecal samples from Spix’s yellow-toothed cavies. Eggs were oval-shaped, with slightly unequal poles, and a thin and smooth shell, measuring 31.87 µm in length and 24.78 µm in width, with two to eight blastomeres in their interior (Figure 1). All groups showed moderate infection on day zero. Group A exhibited mild excretion of eggs after treatment and then moderate infection on day six. Group B had moderate egg counts on day three and high infection on day six when a peak of 1250 epg was recorded. Egg excretion intensity declined in group C, which showed mild infection on days three and six, when we registered the lowest values for epg (50 epg). No gastrointestinal disorder was observed during the experimental trial.

Figure 1. Eggs of Ancylostomidae at different stages of development obtained from fecal
samples of Spix’s yellow-toothed cavies ( Galea spixii Wagle, 1981).

We found significant differences in microclimate conditions between days zero and six (Table 1). Thermal environment and treatments (i.e. infection levels) did not affect TR (P > 0.05). Mean surface temperatures were greater on day six (P < 0.01) for all regions analyzed. Thermograms showed regional differences in surface temperature (Figure 2). TS was most elevated in the ocular surface and auricular temperature was higher than the body surface (Figure 3).

Table 1. Means values, minimum, and maximum of the meteorological variables (atmospheric temperature, relative humidity, wind speed, mean radiant temperature, radiant heat load) at different trial days.


Trial day




Atmospheric temperature (TA, °C)









Relative humidity (RH, %)









Wind speed (U, m s-1)









Mean radiant temperature (TMR, °C)









Radiant heat load (RHL, W m−2)









* Means differ significantly at 1% probability.

Figure 2. Thermograms of Spix’s yellow-toothed cavies (Galea spixii Wagle 1981) from the
Multiplication Center of Wild Animals, Federal Rural University of Semiarid, Brazil.

Figure 3. Regional differences on surface temperature and rectal temperature of Spix’s
yellow-toothed cavies Galea spixii Wagle, 1981) between trial days.
* Means differ significantly between the trial days (P < 0.01).


Reports on gastrointestinal nematodes in Galea spixii are rare; only parasitism by Vianella lenti Durette-Desset (1968) and Hassalstrongylus zetta Durette-Desset (1971) has been described in Brazil (Vicente et al 1997). Our study is, to our knowledge, the first report of parasitism by Ancylostomidae in Spix’s yellow-toothed cavies. The infection is possibly a result of inter-species transmission. Ancylostomidae nematodes parasitize the small intestines of mammals, herbivores, and carnivores. Oral or percutaneous infections as well as colostral transmission are possible, depending on the gender involved (Durette-Dessete et al 1994).

AGE has been effective in controlling Ancylostomidae infection in captive Spix’s yellow-toothed cavies; we observed decreased egg counts in the group treated with a high-concentration extract. Similar findings were reported by Riad et al (2007, 2009) and El Shenaway et al (2008) in Schistosoma infections. The anthelmintic action of garlic can be attributed to an enhanced immune response of the host (Kamel and El-Shinnawy 2015). El Shenaway et al (2008) observed a reduction in mature egg count and number of recovered adult stages in murine infection after AGE treatment. Riad et al (2009) found that garlic caused several damages in parasite tegument, such as edema and blebbing. Among ultrastructural changes observed were vacuolation and disruption of the tegumental matrix, lytic degeneration of the tegumental cells, and necrosis of the parenchymal cells.

Ancylostomidae nematodes were non-pathogenic in Spix’s yellow-toothed cavies in the conditions of this study. Although microclimate and rectal temperatures did not differ significantly between the trial days, body surface temperature increased in each region analyzed. This suggests that the Spix’s yellow-toothed cavy responds to slight variations in its thermal environment, activating the non-evaporative pathway of thermolysis to maintain homeothermy.


Conflict of interest

The authors declare no conflicts of interest.


Amin M R, Mostofa M, Awal M A and Sultana M A 2008 Effects of garlic, turmeric and betel leaf against gastrointestinal nematodes in cattle. Bangladesh Journal of Veterinary Medicine, Volume 6, Pages 115-119, Retrieved from

Anderson R C 2000 Nematode Parasites of Vertebrates: Their Development and Transmission. CABI Publishing, Wallingford.

Balasenthil S, Rao K S and Nagini S 2002 Garlic induces apoptosis during 7,12-dimethylbenz[a]anthracene induced hamster buccal pouch carcinogenesis. Oral Oncology, Volume 38, Pages 431-436, Retrieved from

Burke J M, Wells A, Casey P and Miller JE 2009 Garlic and papaya lack control over gastrointestinal nematodes in goats and lambs. Veterinary Parasitology, Volume 159, Pages 171-174, Retrieved from

Da Silva R G, Guilhermino M M and Morais D A E F 2010 Thermal radiation absorbed by dairy cows in pasture. International Journal of Biometeorology, Volume 54, Pages 5-11.

Dkhil M A, Abdel-Baki A S, Wunderlich F, Sies H and Al-Quraishy S 2011 Anticoccidial and antiinflammatory activity of garlic in murine Eimeria papillata infections. Veterinary Parasitology, Volume 175, Pages 66-72, Retrieved from

Durette-Desset M-C, Beveridge I and Spratt D M 1994 The origins and evolutionary expansion of the Strongylida (Nematoda). International Journal of Parasitology, Volume 24, Pages 1139-1165, Retrieved from

El Shenawy N S, Soliman M F M and Reyad S I 2008 The effect of antioxidant properties of aqueous garlic extract and Nigella sativa as anti-schistosomiasis agents in mice. Revista do Instituto de Medicina Tropical, Volume 50, Pages 29-36, Retrieved from

Fridman S, Sinai T and Zilberg D 2014 Efficacy of garlic based treatments against monogenean parasites infecting the guppy (Poecilia reticulata (Peters)). Veterinary Parasitology, Volume 203, Pages 51-58, Retrieved from

Gordon H M and Whitlock H V A 1939 New technique for counting nematodes eggs in sheep faeces. Journal Council for Scientific and Industrial Research, Volume 12, Pages 50-52.

Hoffman W A, Pons J A and Janer J L 1934 Sedimentation concentration method in schistosomiasis mansoni. Puerto Rico Journal of Public Health and Tropical Medicine, Volume 9, Pages 283-298.

Kamel R O A and El-Shinnawy N A 2015 Immunomodulatory effect of garlic oil extract on Schistosoma mansoni infected mice. Asian Pacific Journal of Tropical Medicine, Volume 8, Pages 999-1005, Retrieved from

Khalil A M, Yasuda M, Farid A S, Desouky M I, Mohi-Eldin M M, Haridy M and Horii Y 2015 Immunomodulatory and antiparasitic effects of garlic extract on Eimeria vermiformis-infected mice. Parasitology Research, Volume 114, Pages 2735-2742.

Lanzotti V, Barile E, Antignani V, Bonanomi G and Scala F 2012 Antifungal saponins from bulbs of garlic, Allium sativum L. var. Voghiera. Phytochemistry, Volume 78, Pages 126-134, Retrieved from

McCafferty D J 2007 The value of infrared thermography for research on mammals: previous applications and future directions. Mammal Review, Volume 37, Pages 207-223, Retrieved from

Moghadam F J, Navidifar T and Amin M 2014 Antibacterial activity of garlic (Allium sativum L.) on multi-drug resistant Helicobacter pylori isolated from gastric biopsies. International Journal of Enteric Pathogens, Volume 2, Page e16749, Retrieved from

Peni I J, Ajagbonna O P, Elinge C M, Agaie B M, Elsa A T, Yusuf H and Ribah I M 2012 Effects of Allium sativum bulb extract, diminazene aceturate and their combination on parasitaemia, and biochemical indices in rats experimentally infected with Trypanosoma brucei brucei. Journal of Applied Pharmaceutical Science, Volume 2, Pages 112-115, Retrieved from

Riad N H, Fares N H, Mostafa O M and Mahmoud Y I 2007 The effect of garlic on some parasitological parameters and on hepatic tissue reactions in experimental schistosomiasis mansoni. Journal of Applied Sciences Research, Volume 3, Pages 949-960.

Riad N H A, Taha H A and Mahmoud Y I 2009 Effects of garlic on albino mice experimentally infected with Schistosoma mansoni: A parasitological and ultrastructural study. Tropical Biomedicine, Volume 26, Pages 40-50.

Riad N H A, Taha H A and Mahmoud Y I 2013 Effects of garlic on Schistosoma mansoni harbored in albino mice: Molecular characterization of the host and parasite. Gene, Volume 518, Pages 287-291, Retrieved from

Rodrigues V C, Silva I J O, Vieira F M C and Nascimento S T 2011 A correct enthalpy relationship as thermal comfort index for livestock. International Journal of Biometeorology, Volume 55, Pages 455-459.

Da Silva R G and Maia A S C 2013 Principles of Animal Biometeorology. Springer, New York.

Souza R P, Souza J N, Menezes J F, Alcântara L M, Soares N M and Teixeira M C A 2013 Human infection by Trichostrongylus spp. in residents of urban areas of Salvador city, Bahia, Brazil. Biomédica, Volume 33, Pages 439-445, Retrieved from

Speakmann J R and Ward S 1998 Infrared thermography: principles and applications. Zoology, Volume 101, Pages 224-232.

Sutton G A and Haik R 1999 Efficacy of garlic as an anthelmintic in donkeys. Israel Journal of Veterinary Medicine, Volume 54, Pages 66-78.

Tattersall G J and Cadena V 2010 Insights into animal temperature adaptations revealed through thermal imaging. Imaging Science Journal, Volume 58, Pages 261-268, Retrieved from

Velkers F C, Dieho K, Pecher F W M, Vernooij J C M, van Eck J H H and Landman W J M 2011 Efficacy of allicin from garlic against Ascaridia galli infection in chickens. Poultry Science, Volume 90, Pages 364-368, Retrieved from

Vicente J J, Rodrigues H O, Gomes D C and Pinto R M 1997 Nematóides do Brasil. Parte V: Nematóides de mamíferos. Revista Brasileira de Zoologia, Volume 14, Pages 1-452, Retrieved from

Walker J G and Morgan E R 2014 Generalists at the interface: Nematode transmission between wild and domestic ungulates. International Journal for Parasitology: Parasites and Wildlife, Volume 3, Pages 242-250, Retrieved from

Received 1 June 2016; Accepted 7 July 2016; Published 1 August 2016

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