This study investigates the therapeutic potential of neem (Azadirachta indica) extract as a topical remedy for mange in West African Dwarf (WAD) goats, a breed commonly raised in Southern Nigeria and are affected by mange, which negatively impacts animal welfare and productivity. Twelve mange-infected goats were randomly assigned to three treatment groups: T1 (10 ml ivermectin pour-on), T2 (5 ml neem extract + 5 ml ivermectin), and T3 (10 ml neem extract). Treatments were administered topically over 14 day period. Clinical evaluations included skin scrapings, red blood cell (RBC), white blood cell (WBC) and serum biochemical indices. Phytochemical analysis of the neem extract revealed notable concentrations of alkaloids, saponins, and phenols. Post-treatment observations showed improvement in skin condition across all groups. Notably, T2 goats exhibited significant increases in RBC and WBC counts (p < 0.05). Differences in serum biochemical indices, particularly potassium, were also noted. The findings indicate that neem extract, can serve as an effective alternative or adjunct treatment to ivermectin for mange control in WAD goats. Its use may be particularly beneficial in local environments with poor accesibility to conventional drugs, contributing to improve animal health and production outcomes.
Squamous cell carcinoma (SCC) is a cancerous growth originating from the stratified squamous epithelium and is the most frequently diagnosed oral tumor in horses. This case report describes the clinical, imaging, and histopathological characteristics of gingival SCC in a 23-year-old Budyonny gelding with a history of multiple unsuccessful treatments, including a prior tumor excision attempt. The horse presented with a large, space-occupying soft tissue mass associated with excessive drooling, and lateral tongue protrusion. Laboratory findings were consistent with cancer-related anemia, while diagnostic imaging demonstrated extensive mandibular bone lysis consistent with the tumor’s aggressive nature. Histopathology confirmed grade III gingival SCC, characterized by keratin pearl formation and a high mitotic index. Due to the poor prognosis, high treatment costs, and advanced stage of disease, the owner declined further therapeutic intervention. The horse succumbed to the disease and died 6 months after presentation. This case emphasizes the challenges of managing advanced gingival SCC in equines and underscores the importance of early detection and timely intervention.
The Ouled Djellal White Arab sheep is the predominant breed in the Algerian steppes and high plains, known for its adaptability and meat production. This study examines correlations between mandibular, body, and craniometric measurements in two age groups to establish a reference dataset for archaeozoological applications. Thirty female Ouled Djellal sheep, evenly divided into young adults (2–4 years) and adults (>4 years), were examined. Eight body measurements were recorded pre-slaughter, followed by eight mandibular and sixteen craniometric measurements after bone preparation, with four indices subsequently calculated. Significant correlations were observed between mandibular and body measurements, and between mandibular and craniometric parameters. Correlations were more numerous and stronger in adults (ranging from 0.47 to 0.70) than in young adults (from 0.41 to 0.67). While differences in covariation strength were observed between age groups, some correlations, such as those between thoracic perimeter (TP) and mental foramen length (ML6), and between head length (hL) and aboral height of the ascending branch (MH1) persisted across age groups. Dentition-related measurements correlated more frequently in adults, reflecting skeletal maturity, whereas variability in young adults indicated ongoing growth. These findings highlight the importance of age considerations in morphometric analysis and provide reference data for estimating body size and cranial dimensions from mandible measurements, contributing to archaeozoological studies of North African ancient specimens.
The Uropygial (Preen) gland, located dorsocranially to the pygostyle and rectrices in birds, is a bi-lobed structure responsible for secreting oil for plumage maintenance. This study investigated the morphological and histological features during post-natal development in the Fulani Ecotype chicken (Gallus gallus domestica) with the aim of documenting anatomical information that will be useful for further biomedical and embryological studies. A total of 56 Fulani Ecotype chickens were sampled, and studied across four developmental phases, with each phase comprising 7 males and 7 females. For each bird, live body weight, uropygial gland weights and preen oil weights were documented. Morphometric characteristics of the excised gland were documented before extraction and measuring the preen oil. Additionally, uropygial glands from selected birds per phase were excised, and fixed in 10% buffered formalin solution for gross and histological analysis. The gland appeared as early as week 2–3 post-hatch, presenting two pear shaped lobes and a short papilla. Three layers of the secretory cells were recognised at 7-8 months post hatch. The results confirm that uropygial gland of the Fulani ecotype chicken develops early, at week 2-3 post hatch, and that its weight increases with the body weight, reaching full histological development between 7-8 months post hatch.
This study evaluated possible antagonistic effects of Peganum harmala against the lethal effect of E. carinatus venom. Seventy-two albino mice were divided into 12 equal groups in 6 experimental protocols. In protocol I, Group A (control) treated with venom. They died after 80 min averagely. In protocol II, Groups B1 and B2 were treated with 15 and 30 mg/kg of P. harmala, respectively and 10 mg/kg venom simultaneously. Their survival time increased to 232 and 210 min respectively. In protocol III, groups C1 and C2 were treated with 10 mg/kg venom and after 15 min received P. harmala at 15 and 30 mg/kg respectively. Their time to death was increased to 246 and 220 min respectively. In protocol IV, groups D1 and D2, treated with pre-incubated of venom with P. harmala (30 min) at the previous doses. Their survival time increased to 211 and 195 min respectively. In protocol V groups E1 and E2 received only P. harmala extract (IP) at 15 and 30 mg/kg respectively. In protocol VI, groups F1, F2, and F3 received only P. harmala extract (orally) at doses of 15, 30, and 60 mg/kg respectively, they remained alive. Peganum harmala significantly (p < 0.05) increased animal survival time thus, has an antagonistic effect against lethality effect of Echis carinatus venom, make it a possible antivenom candidate for further investigation.
Bovine brucellosis, caused mainly by Brucella abortus, is an important cows disease that has created a widespread public health problem in humans. Diagnosis primarily relies on serological testing; however, these assays lack sensitivity and, more importantly, specificity. In this study, we tried to compare the performance of serological tests routinely applied in Iran with antigen detection tests. Also, we examined Brucella species circulating in cows of Fars province, Iran. In addition, the infection rate of Yersinia entrocolitica O9 strain as a probable interfering agent in Brucella spp. serological tests were evaluated. Supramammary lymph nodes were sampled from 98 Brucella spp. reactor cows of Fars province, Iran, analyzed by bacterial culture and molecular tests, including conventional, multiplex, and real-time PCR. Brucella spp. was isolated from 5.1% of cultured samples, while conventional and real-time PCR detected in 15 (15.3%) and 21 (21.4%) samples, respectively. All positive samples were identified as B. abortus. Notably, 78.6% of seropositive cows tested Brucella spp. negative by both molecular tests and culture at the time of slaughtering, which showed a high false-positive rate of serological testing. As Y. enterocolitica O9 was not detected in any lymph node samples, it could be concluded that immunological cross-reaction with this bacterium was not the reason for the few real-time PCR-positive results among Brucella reactor cows. In conclusion, real-time PCR provides valuable information about the Brucella species circulating in the slaughtered cows of each region.
Computed tomography (CT) is one of the most practical and accurate diagnostic imaging methods for evaluating the bird’s head. This study aimed to present the normal anatomical data of Rose-ringed parakeet (Psittacula krameri) head using the CT imaging. In this research, the features of this bird's head were investigated in terms of bones, joints, muscles, sinuses, and other constituent tissues. A retrospective cross-sectional study was conducted on of six adult Rose-ringed parakeet carcasses (3 males and 3 females), aged 1–5 years and weighted between 115–125 g. Following preparing the CT images, the heads underwent gross anatomical studies. Based on the results, reconstructed CT images allowed clear identification of most structures, including the parietal, mandible, occiput, maxillary, preimaxillary, palatine, pterygoid, quadrate, and temporal bones, epithelial membranes, external ear canal and bony labyrinth, ossicles, entoglossal bones, different parts of the infraorbital sinus, brain hemispheres, and various parts of the eyeball and nasal conchae. The results related to the CT evaluation and anatomical examination of the Rose-ringed parakeet’s head demonstrated a high correlation. The results of this research provide a valuable reference and can be employ for identifying anatomical features, examining different species of the parakeets, teaching veterinary anatomy, interpreting CT images, and supporting clinical examinations and treatment in this type of parrots.
Bacterial pathogens are a major cause of economic losses in aquaculture and pose serious threat to public health. This study investigates the phenotypic and the genomic characteristics of pathogenic Pseudomonas species in two finfish species, Oreochromis niloticus (Tilapia) and Clarias gariepinus (African catfish), sourced from the Galadima fish market in Kano metropolis, Nigeria. Twenty fish samples, including 10 Tilapia and 10 African catfish were randomly selected and tissue samples (liver, spleen, intestine and gills) were collected for analysis. Pseudomonas spp. were screened via culturing and isolation techniques and biochemical tests. Molecular identification was carried out based on 16S rRNA gene sequence analysis. Out of all the samples analyzed, 6 % tested positive for Pseudomonas spp., including P. putida (5 %), P. aeruginosa (1.25 %), and P. fluorescens (1.25 %). This study confirms the presence of potentially pathogenic Pseudomonas species in commercially important finfish species from the Galadima fish market in Kano, Nigeria. These findings highlight the need for regular monitoring and molecular surveillance of bacterial pathogens in aquaculture products to prevent economic losses and safeguard public health.
The present research aimed to assess the livelihood status of native chicken farmers in Bangladesh, their rate of profitability, constraints, and their suggestions for addressing these issues. Primary data were collected from a random sample of 260 native chicken-rearing farmers across six divisions in Bangladesh. The majority of farms (36.9%) fell into the small category (1–10 chickens), followed by medium (11–15 chickens) and large (>15 chickens) farms (31.9%). Common deshi hens were present in nearly 95% of the farms. In 2023, the market prices for different categories of chicken were as follows: roasters at 329.68 ± 7.20 BDT, hens at 302.22 ± 2.66 BDT, and chicks at 68.23 ± 2.28 BDT. The market prices for duck eggs, native chicken eggs, brown-shelled eggs, and white-shelled eggs ranged from 63.91 ± 0.52 to 61.07 ± 0.58 BDT per hali. The Patuakhali district had the highest benefit-cost ratio of 2.61, while Rangpur had the lowest at 1.57. Native chicken farming contributed 7.79% to household income. A multiple regression analysis revealed that almost all variables were influenced by income from native chicken farming, except for rearing costs. The major constraints reported were disease outbreaks and predatory animal attacks, mentioned by 80.4% of the farmers. In conclusion, native chicken farming in Bangladesh is profitable despite some challenges that need to be addressed.
Feline chronic gingivostomatitis (FCGS) is a severe, immune-mediated, inflammatory disease affecting the oral mucosal of cats. It is characterized by ulcerative and/or proliferative lesions, most commonly located lateral to the palatoglossal folds. Clinically, FCGS can lead to severe malnutrition and dehydration in critical cases. The pathogenesis of FCGS is poorly understood but it is considered a multifactorial disease, likely involving infectious agents and other parameters. FCGS seems to be a manifestation of an aberrant immune response to chronic antigenic stimulation. Disturbance and im balance of the oral microbiota also may play a role in the development of FCGS. Because of its unknown pathogenesis and long disease course, it is difficult to treat and has a high recurrence rate. The current standard of care involves dental extractions of at least all premolar and molar teeth, often in combination medical therapy. Standalone medical management has shown limited long-term efficacy. Emerging regenerative therapies, such as mesenchymal stem cell treatment, offer promising alternatives for management of FCGS.
Widespread application of carbendazim (Carb) in agriculture and veterinary is a major environmental concern because of its residues that disrupt spermatogenesis. Recently, coenzyme Q10 (CoQ10) supplementation has demonstrated various health benefits due to its anti-apoptosis and anti-inflammatory nature. Thus, the present study aimed to investigate the possible mechanistic pathway of CoQ10 in Carb-induced reproductive dysfunction in male rats. Adult male Wistar rats were orally exposed to Carb (150 mg/kg) singly or in combination with CoQ10 (200 mg/kg). The rats received their treatments daily for 9 weeks. At the end of the work, the testis specimens were excised for histological (H & E staining), immunohistochemical, hormonal, and molecular (real-time quantitative PCR) assessments. The Carb group showed adverse testicular alterations confirmed by immunostaining and demonstrated a significant upregulation of Bax and Caspase-3 expression, while exhibiting a notable reduction in the immunopositivity of Bcl-2 protein within the testes of rats. Real-time PCR analysis revealed that Carb treatment decreased the expression of miR-202-5p with a concomitant decline in concentrations of testosterone and LH hormones. Conversely, in Carb-treated rats, co-treatment with CoQ10 restored the tissue architecture, hormonal disturbance, and declined apoptotic index to near control level. In addition, high expression of miR-202-5p was observed in the Carb + CoQ10 group, and testicular tissues returned to nearly normal histological architecture. We concluded that Carb causes adverse testicular alterations via miR-202-5p/apoptosis pathway, and CoQ10 may prove useful in combating Carb-induced adverse effects via its anti-apoptotic and gene regulatory effects.
Behavioral disorders in companion animals, especially dogs, are a great concern. Due to the relationship between oxidative stress and behavior problems and also heavy metals’ capability of creating oxidative stress, in the current study, the effects of lead, mercury, arsenic, and cadmium on 13 common canine behavior problems (fearfulness, excessive barking, destructiveness, house soiling, inappropriate sexual behavior, coprophagia, wandering, shyness, aggression toward the owner, aggression toward familiar people, aggression toward strangers, aggression toward other dogs, and excessive activity) were evaluated. According to owners’ answers to the questionnaire, 43 terrier dogs were chosen. Of these 7 dogs showed no behavior problem and 36 dogs displayed at least one behavior problem. The blood concentrations of lead, mercury, arsenic, and cadmium were measured using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). No significant differences in heavy metal concentrations were observed between the case and control groups. However, the cadmium concentration was significantly elevated in dogs displayed aggressive behavior toward their owners (p < 0.048, n=5). while arsenic level was significantly lower in dogs displaying fearfulness (p = 0.048, n= 25). Results of the study reported here do not support the hypothesis that “blood concentration of heavy metals may influence the occurrence or prevention of common behavioral problems in dogs”. Our results suggest that there may be a direct relationship between higher levels of cadmium and aggression toward the owner and arsenic with reduced fearfulness in dogs. However, we have to consider that the behavioral effects of heavy metals are likely very complex.
Chlamydophila is an important cause of in-utero infections in sheep and goats, resulting in abortion, stillbirth, and the birth of weak offspring. The disease in sheep caused by Chlamydia abortus (C. abortus) has been known as “ovine enzootic abortion”. Notably, it is recognized as a zoonotic disease, which can lead to abortion in humans. Therefore, the present study was carried out to recognize Chlamydia infection in aborted fetuses of domestic small ruminants, including sheep and goats in East Azerbaijan province, northwest Iran. For this purpose, a total of 62 aborted fetuses were obtained from sheep and goat flocks. At necropsy, the fetus was usually well preserved with few gross lesions. The tissue samples were collected for histopathology and molecular studies. The conventional PCR method using specific primers was performed to detect the Chlamydia genome. Additionally, the formalin-fixed tissue samples were routinely processed for histopathological studies. The genome of C. abortus was detected in 33.87% (95%CI: 0.32 ± 0.11) of the examined fetuses. Histopathological examinations presented multifocal hepatitis, pneumonia, and nonsuppurative meningoencephalitis associated with focal hemorrhage in the muscles. In conclusion, the investigation of the C. abortus genome in aborted fetuses with high prevalence rates indicates that this infection can play a notable role in the abortion of sheep and goats in East Azerbaijan. To prevent potential abortions in women who are in close contact with aborting ruminants, effective management and control measures for public health in the region are crucial.
Industrial wastewater contaminates the land, water, and air, causing serious environmental damage. Industrial wastewater can be combustible, reactive, poisonous, or carcinogenic. Therefore, this study aimed to investigate the effects of industrial wastewater on the growth and gross and histoarchitecture of vital organs of male Swiss albino mice. Thirty-two mice of four weeks of age were divided into four groups. Normal drinking water was supplied to the control group of mice. Mice from groups 1, 2, and 3 were provided with normal drinking water mixed with the garment industry's wastewater at concentrations of 5%, 10%, and 20%, respectively, orally up to experimental week 24. Subsequently, the body weights of mice, as well as the weights of their liver, heart, and kidney, were measured after the completion of 24 weeks of treatment of mice with different concentrations of industrial wastewater. Moreover, histopathological changes in the liver, heart, and kidney were investigated. Body weight was decreased in wastewater-treated mice in comparison to control mice. An increase in the weight of the livers of mice treated with wastewater was observed. Nevertheless, the weights of hearts and kidneys were decreased in wastewater-treated mice. Congestion, hepatocellular necrosis, and infiltration of inflammatory cells were observed in the liver. Disruption of connective tissue was evident in the myocardium of the heart of wastewater-treated mice with necrosis and infiltration of inflammatory cells. Moreover, congestion, cellular necrosis, hypertrophied glomerulus, degeneration in renal tubular epithelial cells, and dilated tubules were evident in the kidney. From these findings, it was concluded that industrial wastewater has detrimental effects on the vital organs of mice.
This experiment was performed to determine the effect of ergothioneine’s effect on serum interleukin-6 (IL-6) concentrations after a race of 2000 m in Arabian stallions at the highest possible speed in a hot-dry environment. Twenty-four apparently healthy stallions of the Arabian breed were used. The average weight and age of the horses were 401 ± 32.11 kg and 5.7 ± 0.54 years, respectively. The experimental subjects were split assigned into three units groups of eight stallions each. Group 1 (EXEN) was neither treated with ergothioneine nor exercised. Group II (EXEC) was not treated with ergothioneine but was exercised. The third group (EXEE) was treated with ergothioneine per os at a dose rate of 0.02 mg/kg daily for one month prior to the experiment. Meteorological parameters of the study site were recorded using a dry and wet-bulb thermometer. The stallions in the EXEC and EXEE groups were made to run a race of 2000 m at the highest possible speed (60 Km/h) by trained riders. Samples of Blood samples of 10 ml were collected from all stallions before the experiment and immediately after the experiment and two hours post-experiment. The hematological parameters and concentration of IL-6 were determined in all samples. The concentration of IL-6 was found to be higher significantly higher in the EXEE group than in others, suggesting a modulatory role of ergothioneine. Therefore, it was concluded that ergothioneine enhanced IL-6 following exercise and would be beneficial to for stallions during exercise.
This study evaluated whether intra-hippocampal administration of ABA can modulate learning and memory performance and oxidative stress biomarker activities in the cerebral cortex of rats exposed to rapid eye movement (REM) sleep deprivation. Adult male Wistar rats were cannulated in the CA1 area of the hippocampus. After recovery, the rats were subjected to REM sleep deprivation for 4 days. Then, the groups of REM sleep-deprived (SD) rats were treated with ABA (5, 10, and 15 µg) and ABA (10 µg) + bicuculline (Bic), a competitive GABAA receptor antagonist. Memory and learning were evaluated with the Morris water maze (MWM) and shuttle box tests. Moreover, alterations in catalase levels as an antioxidant enzyme, MDA, and H2O2 as oxidant biomarkers were determined in rat brain cortex. REM SD rats indicated noteworthy learning and memory deficits in both the MWM and shuttle box tests when compared to control rats. However, intra-CA1 injection of ABA (10 µg) decreased cognitive impairment in REM SD rats. Bic (1 μg/rat) could not change ABA (10 µg) effects. In addition, an increase in catalase activity and a decrease in MDA and H2O2 were indicated in the brain cortex of ABA (10 µg) and ABA+ Bic treated groups. Overall, the data showed ABA's aptitude to attenuate REM sleep deprivation-induced learning and memory disruption and oxidative damage in rats. Manipulation of the GABAA receptor failed to inhibit ABA effects in REM SD rats.
Arthropods belong to the invertebrate Phylum Arthropoda, which contains the most species on Earth. Venomous arthropods are among the most important animals that live in abundance in the human environment. The current study gives an overview of the importance of their identification, bites, stings, behavior, biology, and distribution in the geographical region of Iran, West Asia and the Middle East. The databases have been searched comprehensively and the most relevant Published articles and books from 1978 to 2023 were carefully selected based on the most appropriate keywords. Biting and stinging venomous creatures of arthropods, class, order, and family were presented in the tables and their importance and role of each order in the bite, sting and the occurrence of hazards were determined separately. Finally, the methods of preventing their bites and stings were recommended. The phylum of arthropods in Iran has two subphylums including Chelicerata with one Class, five Orders, and 25 families, and Mandibulata with three Classes, nine Orders, and 29 families. They are scattered all over Iran. Their venom apparatus includes venom gland, modified pedipalps, chelicers, stinger in the tail (telson), mouthparts such as hypostome, fangs, appendages (mandibles), proboscis, ovipositor (stinger), and hair (urticating bristles). The importance of venomous animal stings and bites in the training programs of physicians, the medical and nursing staff is very weak or does not exist at all. To achieve and enhance the management efficacy of bites and envenomation, more accurate information about venomous creatures and their venom composition is required.
Tylosin residues (TR) in chicken meat pose potential health risks to consumers. This study aimed to detect and quantify TR in chicken tissues from Ikpa slaughterhouse, Nsukka and evaluate the effect of heat treatment on TR concentrations. Sixty randomly sampled chicken were processed, and their muscle, liver, and kidney tissues were collected and tested for TR at raw and after ten, fifteen , and twenty minutes of cooking and microwaving using enzyme-linked immunosorbent assay (ELISA), four plate test (FPT), and high-performance liquid chromatography (HPLC). Of the 180 tissues, 93 (51.7%) were positive for TR. The prevalence of TR was 40% in muscles, 55% in liver, and 60% were in kidney samples with ELISA. Six liver samples exceeded the maximum residue level (MRL) of100 µg/kg. Cooking and microwaving reduced TR concentrations by 97-100% in muscle and liver tissues using HPLC. The mean inhibition zones decreased by 87-100% after cooking and microwaving using FPT. Chicken at Ikpa slaughterhouse, Nsukka have TR even in concentrations above the MRL but were significantly eliminated (p ˂ 0.05) after 20 minutes of heat treatments (cooking or microwaving). Hence, mitigating the health risks associated with TR in meat requires regular screening and quantification, public awareness campaigns targeting consumers of raw or improperly cooked chicken, strict policies on antibiotics use in poultry, and enhanced meat handling and processing practices in food industry.
Actinomycetes are a vital group of Gram-positive bacteria known for producing a wide range of bioactive secondary metabolites, including important antibiotics. These microorganisms play an essential role in the degradation of organic matter and nutrient cycling, contributing significantly to soil health and fertility. Their capacity to synthesize diverse compounds and the presence of key biosynthetic pathways involving polyketide synthases and non-ribosomal peptide synthetases highlights their potential in antibiotic discovery, particularly against antibiotic-resistant pathogens. This study aimed to isolate and characterize Actinomycetes from fresh sheep feces collected in Ilam Province, Iran, focusing on their antibacterial activity and biosynthetic potential. A total of 86 actinomycete isolates were obtained from fecal samples collected from sheep in 2021. Morphological characterization confirmed all isolates as Gram-positive and filamentous. Molecular identification through PCR amplification of the 16S rRNA gene yielded a product of approximately 640 base pairs for all isolates. Antibacterial screening revealed that 17 isolates exhibited activity against various pathogens, with the highest efficacy observed against Bacillus cereus (62.1%). Molecular analysis also indicated the presence of biosynthetic gene clusters, with 31 isolates (36.05%) bearing non-ribosomal peptide synthetase (NRPS) gene, 15 isolates (17.44%) containing polyketide synthase I (PKS-I), and 16 isolates (18.6%) with polyketide synthase II (PKS-II) genes. This study highlights the significant antibacterial properties and biosynthetic capabilities of actinomycetes from sheep feces, suggesting their potential use in therapeutic, agriculture, and biotechnological applications.
The European badger (Meles meles) is a powerful animal native to Europe and parts of West Asia. The skull imparts the phylogenetic morphology to the skulls of animal species and functions as a safeguard for vital organs, including the brain and eyes. The aim of our study was to improve the current data by providing a comprehensive investigation of the morphology and dimensions of the cranium and mandible of badgers. This information enhances comprehension of radiological and surgical attributes. We conducted anatomical studies and measured the morphometric features. We received the skulls from naturally occurring carcasses. We employed unpaired t-test for statistical analysis. This study demonstrated that the anatomical features of the skull exhibit no discernible differences between badgers and other wild carnivores, such as tiger and wolf. The presence of a twin jugular foramen in the skull of badgers distinguishes them as a distinct characteristic not found in any other carnivorous animals. Moreover, radiographical studies showed two distinct sinuses and a cavity in the skull of badger which is different from dogs. Males and females differ significantly in some morphometric traits, which is entirely consistent with the behavioral and nutritional traits of the animal. Modern imaging techniques, such as CT scans, are necessary for more thorough studies on the skulls of wild carnivores.
