International Journal of Veterinary Science and Medicine最新文献

Currently available antiviral drugs have certain limitations. Therefore, silver nanoparticles (Ag-NPs) have recently received an increasing attention with respect to their antibacterial and antiviral properties. This in-vitro study aimed to investigate the inhibition effect of Ag-NPs on viral replication (bovine herpesvirus-1; BoHV-1 as a model) and to determine the therapeutic, safe and cytotoxic concentrations. The cytotoxicity of MDBK cells induced by different Ag-NPs concentrations was investigated by using the methyl thiazolyl tetrazolium (MTT) assay. The infected, treated and cellular MDBK controls were stained with neutral red (NR) stain to monitor the cytopathic effects (CPEs) of BoHV-1 and the protective effects of Ag-NPs that inhibit the viral infections. Ag-NPs were safe for the MDBK cell culture at a concentration of 24 μg/mL medium. The highest concentrations were cellular toxic with different degrees. Also, Ag-NPs could protect the MDBK cell culture from BoHV-1 infection at a safety concentration (24 μg/mL medium) when incubate a mixture of Ag-NPs suspension and BoHV-1 prior infect cells. In conclusion, Ag-NPs can be used in vitro safely at the recommended concentration to protect the cellular culture against viral replications. Ag-NPs at nontoxic concentrations (24 μg/mL) are capable of inhibiting BoHV-1 when they are administered prior to viral infection.

Newcastle disease (ND) remains an important enzootic disease in chickens in several parts of the world. With the increasing reports of virulence and genetic diversity of the causative agent; Newcastle disease virus (NDV), there is a need to identify the circulating NDV in specific regions. In Oman, to this moment, such information is still lacking. The aim of this study was to isolate and characterize the NDV from ND outbreaks from commercial farms in Oman. Following suspected outbreaks of ND in three commercial farms in 2017, a total of 30 carcasses (10 from each flock) of adult chickens were subjected to necropsy for gross and histopathological examination, virus isolation and molecular methods. Specifically, haemagglutination inhibition (HI) test and reverse transcription-polymerase chain reaction (RT-PCR) assay were used for the virus detection and confirmation, respectively. Lesions were suggestive of viscerotropic velogenic form of ND based on gross and histopathological examinations. Isolation of NDV was present in 4 cases and further confirmed by RT-PCR following the target of the partial fusion protein gene of the viral genome. The sequence of the partial fusion gene was determined and phylogenetic tree was constructed based on the partial length F gene of 4 Omani isolates and 65 previously published NDVs. The findings predicted that the Omani isolates had high homology (99%) with the isolate from Pakistan belonging to genotype VII. Subsequently, the isolated pathotype was identified as the virulent NDV. This study serves as a basic work for further research on the analysis and phenotyping of NDV in the Sultanate of Oman. Improved monitoring and surveillance of the disease is important for proper preventive measures.

Research in the area of injectable anesthetics in dogs requires mindfulness of ventilation, in order to supply artificial oxygen, which is often achieved with special equipment which may be unaffordable for veterinarians in developing countries. This study evaluated the effect of oxygen supplementation in dogs anesthetized with acepromazine-tramadol-propofol. Six Nigerian indigenous dogs were premedicated with intramuscular injection of acepromazine (0.03 mg/kg) and tramadol (5 mg/kg), followed by induction of anesthesia with propofol (4 mg/kg) IV 20 min later. Maintenance of anesthesia for 2 h was achieved with repeated bolus injections of propofol (2 mg/kg) at 10 min interval and anesthetized dogs breathed oxygen. This experimental trial was repeated a week later without oxygen supply as a control. Anesthetic indices, cardiopulmonary parameters, and rectal temperature were recorded at 10 min intervals for 2 h. Duration of anesthesia, duration of recumbency, time to extubation, and time to standing were not significantly (P > .05) different from their respective control values. Mean heart rate progressively decreased from the 60 min interval in both groups of anesthetized dogs. Mean arterial pressure in dogs with supplemented oxygen was similar to the control group. The mean oxygen-haemoglobin saturation was similar in both experimental trials. There was a progressive decrease in rectal temperature from the 60 min interval in both groups of anesthetized dogs. It was concluded that bolus injection of propofol, with and without supplemental oxygen, appeared to be efficacious and relatively safe in acepromazine-tramadol premedicated healthy dogs not undergoing any surgical or diagnostic procedures.

Centrocestus formosanus is a digenean that requires three host species to complete its life cycle. This study was conducted to observe the damage caused by two life stages of the C. formosanus on its host species. The snail Melanoides tuberculata was induced to shed cercariae by exposing to sunlight and specimens of koi carps were experimentally infected with cercariae. Gills of two infected fish were killed and fixed in Bouin’s solution daily for 21 days. Infected fish were continuously fed to a pond heron (Ardeola ralloides) for three weeks and therafter the bird was killed. Small intestine was resected as duodenum, jejunum, and ileum and fixed in formol saline. Gills and small intestine were prepared to study the histopathological damages. Flared opercula with protruding gills and increased respiratory rate were identified as the primary clinical signs of the fish. Encysted metacercariae were observed in the basal, middle and in the apical portion of the gills’ filaments and gradual distortions and extensive proliferation of the cartilage of the gills resulted in loss of the respiratory epithelium. A progression of fibroblast to chondroblast encapsulation of the parasite was observed in the gill of fish as a host response. The duodenum of the heron was severely infected with adult parasites than jejunum and ileum. Flukes were observed in the villi, mucosae, submucosae, and also in the tunica muscularis of the duodenum. In conclusion, this study revealed that the heavy infection of C. formosanus could cause severe pathological lesions in both koi carps and pond heron.

Warm water aquaculture is widely practiced in Kenya and is dominated by the culture of Nile tilapia (Oreochromis niloticus) (75% of total production) followed by African catfish (Clarias gariepinus) at 18%. Aquaculture started in Kenya in 1920’s and has been on upward trend until 2014 when it peaked at 24,096 MT. However, production reduced drastically in the past 3 years, with 14,952 metric tonnes (MT) reported in 2016. Most farmers practice earthen pond based semi-intensive culture system. Commercial intensive culture of Nile tilapia (O. niloticus) in cages in Lake Victoria has grown significantly in the last five years with a production of 12 million kg of fish every cycle (about 8 months). Recirculation aquaculture system (RAS) is also gaining popularity mainly in intensive hatcheries. The freshwater cages have been marred by increasing frequencies of fish kills with obvious financial and environmental implications. Although limited information exists on fish disease outbreaks across the country, certain well known diseases in farmed fish have been reported. These include; fungal, mainly saprolegniasis, bacterial, mainly hemorrhagic disease and pop-eye diseases. Parasites have also been documented in farmed O. niloticus and C. gariepinus. Although prophylactic treatments are used in some hatcheries in order to prevent infections, limited biosecurity measures are in place to prevent diseases in farmed fish. This is because of inadequate knowledge of the economics of fish diseases, poor infrastructure and inadequate human resource specialized in fish diseases. This review describes the aquaculture production and health mangement practices of farmed fish in Kenya in order to document actions required for effective monitoring and regulation of future fish health problems across the country.

There is a high demand for a veterinary education in animal welfare (AW) with different approaches from the academic, society and trade points of view. Latin American (LA) countries members of the World Organization for Animal Health (OIE) are under the urge and should be obligated to teach AW. The aims of this article are to analyze the current drives of change on the importance of teaching animal welfare in LA, the competences recommended from international education organizations for the region, and to provide the contents on the curriculum in AW that a future veterinarian should achieve in the LA scenario, in other words to examine why teaching AW, what should be taught and how. Despite significant advances in introducing AW into veterinary training programs, much remains to be done regarding the future of this field in teaching veterinary science in Spain and LA countries, and in including this science as an independent course in programs at distinct levels to integrate the scientific, ethical and legal aspects of AW. This paper presents a proposal that was constructed with a view towards integrating diverse curricular approaches based on criteria, contents and concepts provided by the researchers and professors who collaborated in the book entitled: Bienestar Animal: Una Visión Global en Iberoamerica [Animal Welfare: A Global Vision in Ibero-America]. To ensure veterinary students will be better equipped to graduate with OIE day 1 competencies in AW, teaching approaches are needed that support project-based learning and gamification, critical thinking, reflection and collaborative learning.

The greater cane rat (Thryonomys swinderianus) demonstrated numerous dermal architectural peculiarities hitherto unreported. This investigation assessed and evaluated certain histologic features of skin samples from the fore and hind limbs, the neck, head, proximal to the ear and oro-nasal regions for follicular evaluations and micro anatomic assessments in the adult species. Twenty wild taken animals of equal gender distribution were used for histologic assessments of structural elements and histo-morphometric evaluations. Hair follicular density, size, distribution and orientations as well as sexual dimorphisms observed in the body regions studied with Motic Image Plus software analysis were also reported. Statistical analysis revealed sexual dimorphism in this feature as females demonstrated significantly higher (P < .05) follicular density and epidermal thickness at about twice the recorded values for males at similar sites evaluated, but half (P < .05) of follicular diameter of values of males. Mean follicular density for oro-nasal area, head, neck, fore and hind limbs were 50 ± 3.55 and 70 ± 3.34n/µm², 16.24 ± 3.02 and 12 ± 4.00, 8.00 ± 2.68 and 83.66 ± 4.08, 8.02 ± 4.00 and 3.23 ± 3.85, 4.32 ± 3.02 and 2.05 ± 2.04 for females and males respectively. Follicular area decreased proportionally with density increase but it was inversely proportional with epidermal thickness in all evaluated regions. This investigation suggests that the peculiarities observed in dermal structures adapt this species to environmental forces, defense and self-preservation including thermoregulation, foraging and predator evasion, whereas histo-morphometric evaluation result suggests that thermoregulation and other skin sensory modalities may differ between genders in the greater cane rat.

Ochratoxin A (OTA) formation prevention is not usually available so counteracting strategies are urgent. This study investigated the toxic effects of OTA on Nile tilapia with trials to neutralize these effects by using some feed additives. Supplements used as one percent (Garlen Extra4, Nigella sativa, Garlen Extra4 plus Nigella sativa and a commercial mycotoxins binder, Fero Bind Pro) were added to 500 ppb/kg OTA-contaminated diet. Fish were fed at 3% body weight per day for 10 weeks. The clinical signs recorded in OTA – intoxicated positive control group were sluggish swimming and off food before death with reduction in survivability (53%) and growth performance. Several post-mortem lesions were in liver, kidneys and spleen. Serum levels of ALT, AST, creatinine and urea were significantly increased with reduction in total protein, albumin and globulin in ochratoxicated fish group compared to the negative control group. Concerning the pathological changes that have been noticed in ochratoxin treated fish were almost completely alleviated in examined tissues of fish that were fed on diet with Garlen Extra4 plus Nigella sativa or Nigella sativa and partially in fish that were fed on diet with Garlen Extra4 or Fero Bind Pro, respectively. Best detoxifying results were obtained by using 30 g/kg Nigella sativa plus 0.1 g/kg Garlen Extra4 followed by Nigella sativa, Garlen Extra4 then Fero Bind Pro as a commercial Mycotoxins binder. It could be concluded that inclusions of 30 g/kg Nigella sativa plus 0.1 g/kg Garlen Extra4 in Oreochromis niloticus (O. niloticus) diets could partially reduce OTA toxic effects.

The objective of this study was to determine the effect of local anesthesia and the number of incisions performed on the physiological blood profile of piglets after surgical castration. A total of 60 male piglets were divided into five groups of 12 each, based on the surgical method employed and the use, or not, of local anesthesia, as follows: surgical castration using one horizontal incision in both testicles with (C1+L) and without (C1) local anesthesia; surgical castration using two vertical scrotal incisions with and without local anesthesia (C2+L and C2); and control piglets which were removed from their pens and held head-down by their hind limbs for approximately 90 s to simulate castration (SIM). Reference blood samples were drawn 24 h before castration (RV), immediately after surgery or simulated castration (PC), and at 24 and 48 h post-castration, to determine physiological profiles including; pH, hematocrit, glucose, electrolytes, lactate, pCO₂ (mmHg), SO₂ (mmHg), and bicarbonate. Results showed increases in lactate and hematocrit immediately after surgical or simulated castration with decreases in pH, HCO₃− and base excess (BE). Surgical castration produced marked alterations of the physiological profile, detected by reduced pH and HCO₃, higher lactate levels and BE alterations. These changes indicated metabolic acidosis that was greater in the piglets castrated surgically with one horizontal incision than in those castrated with two vertical incisions. More research is needed on the use of lidocaine during surgical castration, as it showed no effect on physiological profile in this study, but did alter hematocrit values.