Prevalence and anatomic site of Crassicauda sp. infection,and its use in species identification,in kogiid whales from the mid‐Atlantic United States

The parasitic nematode Crassicauda sp. was initially described in kogiid whales from specimens collected within cervical tissues, uncommon sites of infection for this parasite. Crassicauda sp. has only been reported in Kogia breviceps to date, but no study has yet investigated a large sample of both kogiid species. A 15 yr record of 104 kogiid strandings (K. sima, n = 40; K. breviceps, n = 64) in North Carolina and Virginia, U.S.A. was used to determine the prevalence of Crassicauda sp. across species, within species across sex, and within sex across length and life history categories. Crassicauda sp. was confirmed to be a species‐specific parasite among kogiids infecting only K. breviceps (prevalence = 45%). Within K. breviceps, prevalence was similar (45%) in both immature and mature males, but increased from 10% in immature to 76% in mature females. This study confirmed the cervico‐thoracic distribution of the parasite, and identified a novel site of infection in a previously undescribed exocrine gland associated with the pigmented “false gill slit.” The species‐specific nature of Crassicauda sp. infection, the exocrine gland, and the distinct features of the false gill slit pigmentation associated with the gland, are all useful characters to identify kogiid species in the field.     

Effect of 16 weeks diving practice at two different times of day on the pulmonary function,spirometry measurements and 6-minute walk test data of healthy professional Tunisian scuba divers

The aim of this study was to investigate the effect of time of the day (TOD) and 16 weeks diving practice (16WDP) on the spirometric parameters and 6-min walk test data (6MWT) on professional Tunisian scuba divers. In randomized order, 36 health males divided into 3 groups [morning practice group) (MPG): n = 12; evening practice group (EPG): n = 12; control group (CG) n = 12] participated voluntary in this study. They performed spirometry measurements and 6MWT during two periods: [before-season (June 05–10), and after-season (October 05–10)]. Our results revealed that assessment sessions comprised the following: FVC, FEV1, FEV1/FVC and PEF. Results were analyzed by applying repeated measures analysis of variance ANOVA. The spirometric parameters were similar upon two times of day on both EPG and MPG before the season (i.e. FEV1, FVC). Likewise, our finding revealed a significant decrease in lung functions following the 16 weeks practice of scuba diving upon two times of day. Thus, this period of hyperbaric scuba diving practice lead a significant alteration of lung function parameters with decrease of percent of variation in EPG vs. CEG compared to MPG vs. CMG: (i.e. FEV1, FVC, and PEF). In conclusion, 16 weeks of hyperbaric scuba diving lead a significant change in the spirometric and 6MWT values and respiratory problem with damage on lung function in healthy adult divers older than 40 years. Professional divers are recommended to have practice diving in the morning.     

Predator‐induced modifications to diving behavior vary with foraging mode

Breath‐hold divers are strongly interacting species whose top–down influence on aquatic communities is shaped by factors governing their diving decisions. Although some of these factors (e.g. physiological constraints, energetic needs) have been scrutinized, the possibility that predation risk influences diving behavior has been largely overlooked, and no study to date has asked if anti‐predator responses by divers depend on foraging mode. We contrasted dive cycle changes by herbivorous dugongs Dugong dugon using two foraging tactics – cropping, which always permits anti‐predator vigilance, and excavation, which limits surveillance at depth – in response to temporal variation in tiger shark Galeocerdo cuvier abundance. Dugongs responded to increasing shark abundance (one component of predation risk) by diving more frequently without changing their surface times and thereby spending a greater proportion of time at the surface, but only while excavating. When threatened, in other words, excavating dugongs sacrificed foraging time at depth to facilitate shark detection. In contrast, cropping dugongs at risk from sharks were able to continue diving and foraging normally. By implication, future studies should consider the influence of predation risk on diving decisions, even by large‐bodied species, and the possibility that behavioral responses by divers to predators may vary with foraging mode.     

Pulmonary edema and hemoptysis after breath-hold diving at residual volume.

To simulate pressure effects and experience thoracic compression while breath-hold diving in a relatively safe environment, competitive breath-hold divers exhale to residual volume before diving in a swimming pool, thus compressing the chest even at depth of only 3-6 m. The study was undertaken to investigate whether such diving could cause pulmonary edema and hemoptysis. Eleven volunteer breath-hold divers who regularly dive on full exhalation performed repeated dives to 6 m during a 20-min period. The subjects were studied with dynamic spirometry, video-fibernasolaryngoscopy, and single-breath diffusion capacity of carbon monoxide (Dl(CO)). The duration of dives with empty lungs ranged from 30 to 120 s. Postdiving forced vital capacity (FVC) was reduced from mean (SD) 6.57 +/- 0.88 to 6.23 +/- 1.02 liters (P < 0.05), and forced expiratory volume during the first second (FEV(1.0)) was reduced from 5.09 +/- 0.64 to 4.59 +/- 0.72 liters (P < 0.001) (n = 11). FEV(1.0)/FVC was 0.78 +/- 0.05 prediving and 0.74 +/- 0.05 postdiving (P < 0.001) (n = 11). All subjects reported a (reversible) change in their voice after diving, irritation, and slight congestion in the larynx. Fresh blood that originated from somewhere below the vocal cords was found by laryngoscopy in two subjects. Dl(CO)/alveolar ventilation (Va) was 1.56 +/- 0.17 mmol.kPa(-1).min(-1).l(-1) before diving. After diving, the Dl(CO)/Va increased to 1.72 +/- 0.24 (P = 0.001), but 20 min later it was indistinguishable from the predive value: 1.57 +/- 0.20 (n = 11). Breath-hold diving with empty lungs to shallow depths can induce hemoptysis in healthy subjects. Edema was possibly present in the lower airways, as suggested by reduced dynamic spirometry.     

Diving behavior in a free‐living,semi‐aquatic herbivore,the Eurasian beaver Castor fiber

Semi‐aquatic mammals have secondarily returned to the aquatic environment, although they spend a major part of their life operating in air. Moving both on land, as well as in, and under water is challenging because such species are considered to be imperfectly adapted to both environments. We deployed accelerometers combined with a depth sensor to study the diving behavior of 12 free‐living Eurasian beavers Castor fiber in southeast Norway between 2009 and 2011 to examine the extent to which beavers conformed with mass‐dependent dive capacities, expecting them to be poorer than wholly aquatic species. Dives were generally shallow (<1 m) and of short duration (<30 s), suggesting that the majority of dives were aerobic. Dive parameters such as maximum diving depth, dive duration, and bottom phase duration were related to the effort during different dive phases and the maximum depth reached. During the descent, mean vectorial dynamic body acceleration (VeDBA—a proxy for movement power) was highest near the surface, probably due to increased upthrust linked to fur‐ and lung‐associated air. Inconsistently though, mean VeDBA underwater was highest during the ascent when this air would be expected to help drive the animals back to the surface. Higher movement costs during ascents may arise from transporting materials up, the air bubbling out of the fur, and/or the animals’ exhaling during the bottom phase of the dive. In a manner similar to other homeotherms, beavers extended both dive and bottom phase durations with diving depth. Deeper dives tended to have a longer bottom phase, although its duration was shortened with increased VeDBA during the bottom phase. Water temperature did not affect diving behavior. Overall, the beavers’ dive profile (depth, duration) was similar to other semi‐aquatic freshwater divers. However, beavers dived for only 2.8% of their active time, presumably because they do not rely on diving for food acquisition.     

Signature whistles in free‐ranging populations of Indo‐Pacific bottlenose dolphins,Tursiops aduncus

Common bottlenose dolphins (Tursiops truncatus) use individually distinctive signature whistles which are highly stereotyped and function as contact calls. Here we investigate whether Indo‐Pacific bottlenose dolphins (T. aduncus) use signature whistles. The frequency trace of whistle contours recorded from three genetically distinct free‐ranging populations was extracted and sorted into whistle types of similar shape using automated categorization. A signature whistle identification method based on the temporal patterns in signature whistle sequences of T. truncatus was used to identify signature whistle types (SWTs). We then compared the degree of variability in SWTs for several whistle parameters to determine which parameters are likely to encode identity information. Additional recordings from two temporarily isolated T. aduncus made during natural entrapment events in 2008 and 2009 were analyzed for the occurrence of SWTs. All populations were found to produce SWTs; 34 SWTs were identified from recordings of free‐ranging T. aduncus and one SWT was prevalent in each recording of the two temporarily isolated individuals. Of the parameters considered, mean frequency and maximum frequency were the least variable and therefore most likely to reflect identity information encoded in frequency modulation patterns. Our results suggest that signature whistles are commonly used by T. aduncus.     

Brief communication: Transportation and trauma: Dog‐sledding and vertebral compression in Alaskan Eskimos

Vertebral compression, as evidenced by compression of the centrum, was observed within two Native Alaskan skeletal samples. Information was collected from 1,071 and 656 vertebrae from Golovin Bay and Nunivak Island, Alaska, respectively. In addition, patterns of compression related vertebral change in each collection were characterized by sex and location within the vertebral column. The overall frequencies of vertebral compression were 3.6% (n = 721) at Golovin Bay and 1.7% (n = 403) at Nunivak Island for all observable thoracic and lumbar vertebrae (T1–L5). There was no statistically significant difference in the occurrence of compression among adults between these two collections. When examining the thoracic and lumbar vertebral segments by sex, females at Golovin Bay (4.5%; n = 442) exhibited a significantly higher frequency of vertebral compression than females at Nunivak (1.0%; n = 203). However, this difference in occurrence of compression could be accounted for by the age distributions of the two samples. No difference was noted between the males of the two collections. Compression frequencies in both samples are discussed in relation to the modes of transportation historically utilized by each community. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.     

Symbiont‐conferred reproduction and fitness benefits can favour their host occurrence

Double infections of Wolbachia and Spiroplasma are frequent in natural populations of Tetranychus truncatus, a polyphagous mite species that has been a dominant species in China since 2009. However, little is known about the causes and ecological importance of such coexistences. In this study, we established T. truncatus strains with different infection types and then inferred the impact of the two endosymbionts on host reproduction and fitness. Double infection induced cytoplasmic incompatibility, which was demonstrated by reduction in egg hatchability of incompatible crosses. However, doubly infected females produced more eggs relative to other strains. Wolbachia and Spiroplasma did not affect host survival, whereas doubly infected females and males developed faster than other strains. Such reproduction and fitness benefits provided by double infections may be associated with the lower densities of each symbiont, and the quantitative results also confirmed competition between Wolbachia and Spiroplasma in doubly infected females. These symbiont‐conferred beneficial effects maintain stable prevalence of the symbionts and also help drive T. truncatus outbreaks in combination with other environmental factors.     

Locomotor muscle profile of a deep (Kogia breviceps) versus shallow (Tursiops truncatus) diving cetacean

When a marine mammal dives, breathing and locomotion are mechanically uncoupled, and its locomotor muscle must power swimming when oxygen is limited. The morphology of that muscle provides insight into both its oxygen storage capacity and its rate of oxygen consumption. This study investigated the m. longissimus dorsi, an epaxial swimming muscle, in the long duration, deep‐diving pygmy sperm whale (Kogia breviceps) and the short duration, shallow‐diving Atlantic bottlenose dolphin (Tursiops truncatus). Muscle myoglobin content, fiber type profile (based upon myosin ATPase and succinate dehydrogenase assays), and fiber size were measured for five adult specimens of each species. In addition, a photometric analysis of sections stained for succinate dehydrogenase was used to create an index of mitochondrial density. The m. longissimus dorsi of K. breviceps displayed significantly a) higher myoglobin content, b) larger proportion of Type I (slow oxidative) fibers by area, c) larger mean fiber diameters, and d) lower indices of mitochondrial density than that of T. truncatus. Thus, this primary swimming muscle of K. breviceps has greater oxygen storage capacity, reduced ATP demand, and likely a reduced rate of oxygen consumption relative to that of T. truncatus. The locomotor muscle of K. breviceps appears able to ration its high onboard oxygen stores, a feature that may allow this species to conduct relatively long duration, deep dives aerobically. J. Morphol., 2013. © 2013 Wiley Periodicals, Inc.     

Cut‐off values and significance of Oil Red O‐positive cells in bronchoalveolar lavage fluid

C. Basset‐Léobon, L. Lacoste‐Collin, J. Aziza, J.C. Bes, S. Jozan and M. Courtade‐Saïdi
Cut‐off values and significance of Oil Red O‐positive cells in bronchoalveolar lavage fluid Objective: To evaluate the percentage and predictive value of Oil Red O‐positive macrophages (ORO‐PM) to identify lipid‐laden macrophages in bronchoalveolar lavage fluids (BALF) from patients with different pathologies. Methods: The percentage and absolute numbers of ORO‐PM were evaluated in 305 BALF. The patients were separated into ten groups: corticosteroid treatment (n = 18), amiodarone treatment (n = 8), interstitial fibrosis (n = 11), human immunodeficiency virus (HIV)‐positive (n = 25), infectious pneumonia (n = 43), severe haematological disorder (n = 25), interstitial syndrome (n = 109), suspicion of cancer (n = 17), transplant recipients (n = 50) and controls (n = 43). The total and differential cell counts in BALF were recorded. The presence of specific pathogens was also noted. Parametric and non‐parametric tests were used to compare the values between groups. Receiver–operating characteristics (ROC) curves were established in order to determine a cut‐off value. Results: The percentages of ORO‐PM were (mean ± standard deviation) 21.67 ± 29.12 in the corticosteroid group, 10.00 ± 12.49 in the amiodarone group, 19.45 ± 20.72 in the interstitial fibrosis group, 47.80 ± 30.46 in the HIV group, 19.72 ± 26.26 in the infectious pneumonia group, 27.42 ± 30.04 in the severe haematological disorder group, 25.18 ± 30.63 in the interstitial syndrome group, 17.64 ± 27.76 in the suspicion of cancer group, 22.50 ± 27.27 in the transplanted recipients group and 2.63 ± 3.48 in the control group. Significantly higher values were found in all groups when compared with the control group (P < 0.001). Only the HIV group showed higher numbers of ORO‐PM when compared with the interstitial syndrome group (P < 0.01). According to ROC curves, > 6% ORO‐PM was suggested as the positive cut‐off value. Conclusion: Significantly increased numbers of ORO‐PM were associated with various lung pathologies. However, the higher numbers observed in HIV patients require further investigations.     

A day in the life of a dolphin: Using bio‐logging tags for improved animal health and well‐being

Little quantitative information on the behavior, health, and activity level of managed marine mammals is currently collected, though it has the potential to significantly contribute to management and welfare of these animals. To address this, high‐resolution motion‐sensing digital acoustic recording tags (DTAGs) collected data from animals under human care (n = 5) during their daily routine, and classification algorithms were used for gait analysis and event detection. We collected and examined ~57 h of data from five bottlenose dolphins (Tursiops truncatus). Day‐scale changes in behavior and activity level were observed and diurnal changes were detected with lower activity at night (n = 1). During the day, animals spent about 70% of their time swimming. The deepest part of the lagoon is ~3 m and individual dives were typically shallow (~1 m) with the dolphins tending to utilize a fluke and glide gait pattern. Activity level was quantified using overall dynamic body acceleration. A significant relationship between normalized activity level and glide duration during different portions of the dive was measured; animals fluked more during descent and glided more during ascent. This could indicate that even during very shallow dives the dolphins use their positive buoyancy to improve energy economy.     

Changes in Nkx2.1, Sox2, Bmp4, and Bmp16 expression underlying the lung‐to‐gas bladder evolutionary transition in ray‐finned fishes

The key to understanding the evolutionary origin and modification of phenotypic traits is revealing the responsible underlying developmental genetic mechanisms. An important organismal trait of ray‐finned fishes is the gas bladder, an air‐filled organ that, in most fishes, functions for buoyancy control, and is homologous to the lungs of lobe‐finned fishes. The critical morphological difference between lungs and gas bladders, which otherwise share many characteristics, is the general direction of budding during development. Lungs bud ventrally and the gas bladder buds dorsally from the anterior foregut. We investigated the genetic underpinnings of this ventral‐to‐dorsal shift in budding direction by studying the expression patterns of known lung genes (Nkx2.1, Sox2, and Bmp4) during the development of lungs or gas bladder in three fishes: bichir, bowfin, and zebrafish. Nkx2.1 and Sox2 show reciprocal dorsoventral expression patterns during tetrapod lung development and are important regulators of lung budding; their expression during bichir lung development is conserved. Surprisingly, we find during gas bladder development, Nkx2.1 and Sox2 expression are inconsistent with the hypothesis that they regulate the direction of gas bladder budding. Bmp4 is expressed ventrally during lung development in bichir, akin to the pattern during mouse lung development. During gas bladder development, Bmp4 is not expressed. However, Bmp16, a paralogue of Bmp4, is expressed dorsally in the developing gas bladder of bowfin. Bmp16 is present in the known genomes of Actinopteri (ray‐finned fishes excluding bichir) but absent from mammalian genomes. We hypothesize that Bmp16 was recruited to regulate gas bladder development in the Actinopteri in place of Bmp4.     

Features of glossopharyngeal breathing in breath-hold divers.

One technique employed by competitive breath-hold divers to increase diving depth is to hyperinflate the lungs with glossopharyngeal breathing (GPB). Our aim was to assess the relationship between measured volume and pressure changes due to GPB. Seven healthy male breath-hold divers, age 33 (8) [mean (SD)] years were recruited. Subjects performed baseline body plethysmography (TLC(PRE)). Plethysmography and mouth relaxation pressure were recorded immediately following a maximal GPB maneuver at total lung capacity (TLC) (TLC(GPB)) and within 5 min after the final GPB maneuver (TLC(POST)). Mean TLC increased from TLC(PRE) to TLC(GPB) by 1.95 (0.66) liters and vital capacity (VC) by 1.92 (0.56) liters (P < 0.0001), with no change in residual volume. There was an increase in TLC(POST) compared with TLC(PRE) of 0.16 liters (0.14) (P < 0.02). Mean mouth relaxation pressure at TLC(GPB) was 65 (19) cmH(2)O and was highly correlated with the percent increase in TLC (R = 0.96). Breath-hold divers achieve substantial increases in measured lung volumes using GPB primarily from increasing VC. Approximately one-third of the additional air was accommodated by air compression.     

Differential antioxidant protection in tissues from marine mammals with distinct diving capacities. Shallow/short vs. deep/long divers

The diving response in marine mammals results in bradycardia and peripheral vasoconstriction, with blood flow redistributing preferentially to nervous and cardiac tissues. Therefore, some tissues are rendered ischemic during a dive; with the first breath after a dive, blood flow to all tissues is reestablished. In terrestrial mammals, reactive oxygen species (ROS) production increases in response to ischemia/reperfusion and oxidative damage can occur. The capacity of marine mammals to tolerate repeated ischemia/reperfusion cycles associated with diving appears to be due to an enhanced antioxidant system. However, it is not known if diving depth and/or duration elicit differences in tissue capacity to produce ROS and antioxidant defenses in marine mammals. The objective of this study was to analyze ROS production, antioxidant defenses and oxidative damage in marine mammal species that perform shallow/short vs. deep/long dives. We measured production of superoxide radical (O₂^??), oxidative damage to lipids and proteins, activity of antioxidant enzymes, and glutathione levels in tissues from shallow/short divers (Tursiops truncatus) and deep/long divers (Kogia spp.). We found that differences between the diving capacity of dolphins and Kogia spp. are reflected in O₂^?? production and antioxidant levels. These differences suggest that shallow/short and deep/long divers have distinct mechanisms to successfully maintain redox balance.     

CETACEAN ABUNDANCE IN HAWAIIAN WATERS ESTIMATED FROM A SUMMER/FALL SURVEY IN 2002

Cetacean abundance is estimated for the U.S. Exclusive Economic Zone (EEZ) around the Hawaiian Islands based on a ship line‐transect survey from August to November, 2002. Sighting detection functions are estimated from this and other NOAA research surveys from 1986 to 2002 using a new, multiple‐covariate approach. Twenty‐four species were seen on this survey, including two species (Fraser's dolphin [Lagenodelphis hosei] and sei whale [Balaenoptera borealis]) that had not been previously documented to occur in Hawaiian waters. The most abundant large whales are sperm whales (Physeter macrocephalus) and Bryde's whales (Balaenoptera edeni). The most abundant delphinids are pilot whales (Globicephala macrorhynchus), rough‐toothed dolphins (Steno bredanensis), Fraser's dolphins, spotted dolphins (Stenella attenuata), and striped dolphins (Stenella coeruleoalba). Dwarf and pygmy sperm whales (Kogia sima and Kogia breviceps) and Cuvier's beaked whales (Ziphius cavirostris) are also estimated to be quite abundant. Some of the migratory baleen whales (fin whales [Balaenoptera physalus], sei whales, minke whales [B. acutorostrata], and humpback whales [Megaptera novaeangliae]) were seen only late in the survey. Abundance is estimated for 19 cetacean species. The overall density of cetaceans is low in the study area, especially for delphinids. The precision of density and abundance estimates is generally low for all species because of the low number of sightings.     

Comparing total body lipid content of young‐of‐the‐year Steller sea lions among regions of contrasting population trends

Steller sea lion (Eumetopias jubatus) young‐of‐the‐year (YOY) are nutritionally dependent upon their dam through the majority of their first year. Several indices of body condition were measured in YOY 1.5–9 mo of age captured in Southeast Alaska (n = 122), the Gulf of Alaska (n = 182), and the Aleutian Islands (n = 38) to test the hypothesis that nutritional stress impacted the ability of adult female Steller sea lions to adequately nourish their late gestation YOY in the central Aleutian Islands in the early 2000s. Body mass (kg) and percent total body lipid content (%TBL) increased with age in all three regions of Alaska that were sampled (P < 0.05). Young‐of‐the‐year 7–9 mo of age were leaner in Southeast Alaska (27.6% ± 1.0%) and Gulf of Alaska (29.5% ± 0.8%) than in the Aleutian Islands (35.7% ± 1.2%, P < 0.001). Condition indices calculated from morphometric measures did not strongly predict the %TBL measured by isotope dilution. The trend for Aleutian Island YOY to have larger body mass and larger body fat reserves are counter to what would be expected if dams were unable to adequately provision their late lactation YOY due to inadequate food availability in the central Aleutian Islands.     

Intrinsically altered lung‐resident γδT cells control lung melanoma by producing interleukin‐17A in the elderly

Cancer is an age‐associated disease, potentially related to the altered immune system of elderly individuals. However, cancer has gradually decreased incidence in the eldest globally such as the most common lung cancer, the mechanisms of which remain to be elucidated. In this study, it was found that the number of lung‐resident γδT cells was significantly increased with altered gene expression in aged mice (20–24 months) versus young mice (10–16 weeks). Aged lung Vγ4⁺ and Vγ6⁺ γδT cells predominantly produced interleukin‐17A (IL‐17A), resulting in increased levels in the serum and lungs. Moreover, the aged mice exhibited smaller tumors and reduced numbers of tumor foci in the lungs after challenge with intravenous injection of B16/F10 melanoma cells compared with the young mice. Aged lung Vγ4⁺ and Vγ6⁺ γδT cells were highly cytotoxic to B16/F10 melanoma cells with higher expression levels of CD103. The markedly longer survival of the challenged aged mice was dependent on γδT17 cells, since neutralization of IL‐17A or depletion of indicated γδT cells significantly shortened the survival time. Consistently, supplementation of IL‐17A significantly enhanced the survival time of young mice with lung melanoma. Furthermore, the anti‐tumor activity of aged lung γδT17 cells was not affected by alterations in the load and composition of commensal microbiota, as demonstrated through co‐housing of the aged and young mice. Intrinsically altered lung γδT17 cells underlying age‐dependent changes control lung melanoma, which will help to better understand the lung cancer progression in the elderly and the potential use of γδT17 cells in anti‐tumor immunotherapy.     

The application of anti‐ESAT‐6 monoclonal antibody fluorescent probe in ex vivo near‐infrared fluorescence imaging in mice with pulmonary tuberculosis

Here, we aimed to assess the feasibility of anti‐ESAT‐6 monoclonal antibody (mAb) coupling with IR783 and rhodamine fluorescent probe in the detection of ESAT‐6 expression in tuberculosis tissue of mice using near‐infrared fluorescence imaging. IR783 and rhodamine were conjugated to the anti‐ESAT‐6 mAb or IgG. Mice in the experimental group were injected with fluorescence‐labeled mAb probe, and mice in the control group were injected with fluorescence‐labeled non‐specific IgG antibody. Twenty‐four hours later, the lung tissue of mice was examined using ex vivo near‐infrared fluorescence imaging. In addition, the contrast‐to‐noise ratio (CNR) was calculated by measuring the signal intensities of the pulmonary lesions, normal lung tissue and background noise. The frozen lung tissue section was examined under fluorescence microscopy and compared with hemoxylin and eosin (HE) staining. The ex vivo near‐infrared fluorescence imaging showed that the fluorescence signal in the lung tuberculosis lesions in the experimental group was significantly enhanced, whereas there was only a weak fluorescence signal or even no fluorescence signal in the control group. CNR values were 64.40 ± 7.02 (n = 6) and 8.75 ± 3.87 (n = 6), respectively (t = 17.01, p < 0.001). The fluorescence accumulation distribution detected under fluorescence microscopy was consistent with HE staining of the tuberculosis region. In conclusion, anti‐ESAT‐6 mAb fluorescent probe could target and be applied in specific ex vivo imaging of mice tuberculosis, and may be of further use in tuberculosis in living mice. Copyright © 2013 John Wiley & Sons, Ltd.