BACKGROUND: Dactylogyrus is one of the most common external parasites on                the gills of Cyprind fish. These parasites are highly host specific and many species only have a specific host. OBJECTIVES: Since there are reports of silver carp specific Dactylogyrus species isolated from big head carp and vice versa, the investigation of Dactylogyrids have been done in these two fish species. METHODS: 81 silver carp and 82 big head carp were caught from 10 fish farms in Guilan province and after preparing wet mounts of body surface Dactylogyrus parasites divided and fixed by glycerin jelly. In order to perform morphometric assessments on captured images, Image J software was used for 7 point to point distances. Drawing of parasites was done by drawing tube and then compared by identification keys and parasites identified. For molecular investigation the genomic DNA was extracted from one parasite specimen and 28S rDNA region of Dactylogyrus specimens were amplified by related primers in PCR. RESULTS: Sequences were deposited in GenBank with accession numbers MG825611 and MG825765 respectively for D. hypophthalmichthys and D. suchengtaii isolated from Hypophthalmichthys molitrix, and also MH023397 and MH023399 respectively for D. aristichthys and D. nobilis isolated from Hypophthalmichthys nobilis. The phylogenetic tree shows the genetic affinity of isolated parasites from these two fish. CONCLUSIONS: It seems hybrid fish are sometimes produced accidentally in fish reproduction centers of Iran. Racial impurity of silver carp and big head carp is not only the reason of poorer breeding efficiency in fish farms but also these hybrid fish are hosts of more parasitic species.

BACKGROUND: Major histocompatibility complex (MHC) is a group of genes which codes for binding of antigenic peptides and presenting them to T cells. MHC molecules polymorphism is associated with presenting different antigens, immune and autoimmune responses. One of the most important dog MHC genes is DRB1. The association between this gene and its alleles with Atopic Dermatitis has been reported. OBJECTIVES: In this study, the association between canine Atopic Dermatitis and DLA-DRB1 alleles has been evaluated using HRM (High Resolution Melting) genotyping method. METHODS: Blood samples were collected from 20 dogs with Atopic Dermatitis and 20 healthy dogs. Frequency of different DRB1 genotypes, as well as heterozygosity and homozygosity of alleles were analyzed using HRM. Their associations with Atopic Dermatitis were evaluated by statistical analysis. RESULTS: Based on the HRM analysis, genotypes were grouped in 9 types (A-I). Statistical analysis showed that the presence of type D allele in the exon II of DLA-DRB1 gene increases the risk of Atopic Dermatitis (Odd ratio=0.206 and p < /em>=0.064). A significantly increased risk of Atopic Dermatitis in heterozygous samples was also observed (Odd=0.158 and p < /em>=0.090). CONCLUSIONS: The results of this study showed that some alleles of DLA-DRB1 gene can play a role in the sensitivity or resistance to Atopic Dermatitis in dogs.

BACKGROUND: Phosphorous is an essential nutrient for poultry. Receiving too much phosphorous by livestock and excretion of excess phosphorus, can lead to environmental pollution. OBJECTIVES: Determining the ileal and total tract digestibility of phosphorus and calcium in di-calcium phosphates produced in Iran. METHODS: A total of 720 day-old male Ross 308 broilers were randomly divided into 8 treatments with 6 replicates of 15 birds in each. In control treatment phosphoric acid was used as a source of phosphorus. The other dietary treatments included one of the seven domestic samples of di-calcium phosphates (A to G). Chromium oxide was used as a marker in the diets. On day 21, after collecting of feces, all birds were slaughtered via neck dislocation. Then, the last one-third of ileum was removed. The contents of the intestine were collected for each replicate and after drying were sent to the laboratory to determine the chromium oxide, phosphorus, and calcium amounts. Percentage of ileal and total tract digestibility of phosphorus and calcium for each sample were calculated separately. RESULTS: The effect of type of di-calcium phosphate samples in feed on ileal and total tract digestibility of calcium and phosphorus was highly significant (p < /em> < 0.001). Ileal digestibility in control was 69.8 percentage, while the lowest was observed in the E and F samples, and the highest value was related to sample A. Digestibility for phosphorus in control diet was 53.4 percentage throughout gastrointestinal tract. The lowest amounts of total tract digestibility of phosphorus were observed in treatments E and F, respectively, while the highest total tract digestibility was related to treatment A with 47.9 per cent. CONCLUSIONS: It could be concluded that ileal digestibility is more accurate in evaluating phosphorus bioavailability and sample A had the highest biological value, while the lowest was related to the samples E and F.

BACKGROUND: Arrhythmias play an important role in reducing the performance of racing horse. There are no studies that maintained the same condition for all horses, and in previous studies, the conditions for all horses were not the same. OBJECTIVES: The purpose of this study was to evaluate the prevalence of arrhythmias during exercise include warm-up and trotting. METHODS: This study was carried out on 30 sport horses. Modified base-apex has been used for electrocardiogram recording. Electrocardiogram was taken by telemetry device in all conditions, all horses were examined in the electric lounge. Warm-up period was 10 minutes and consequently 10 minutes trotting was done, and ECG was recorded during exercise. RESULTS: 18 horses had SVPCs during warm-up and 9 showed SVPCs during trotting; also, 4 horses showed VPCs during trotting. AVB II happened in one horse during warm-up. CONCLUSIONS: The occurrence of SVPCs and VPCs during rest is abnormal, but it is common during physical activity. To better understand the importance of these arrhythmias more studies are needed.

BACKGROUND: The Schirmer tear test (STT) is widely used in both human and veterinary ophthalmology. Two types of STTs have been developed: STT I and STT II. OBJECTIVES: The purpose of this research was to determine the reference value for measuring tear production of the Caspian horse by using the Schirmer tear test strip. METHODS: Twenty apparently healthy male and female Caspian horses, aged between 2 and 15 years old and weighing between 192±32 Kg were selected. After physical examination and reviewing the horse's health history and assuring their health, the Schirmer tear test was performed. To produce a higher volume of tears in horses, compared to other animal species, we used the Schirmer tear strip (Schirmer‐ Eickemeyer®, Germany), for 30 seconds instead of one minute in the lower conjunctival sac. In this study, we investigated the effect of age and gender on tear production in the Caspian horse, as well as the comparison between the left and right eyes tear production. RESULTS: The study shows that the results of STT I in the study animals illustrated the mean±SD STT I value was 23.38±3.6 mm/min (range, 15–30 mm/30s). Based on the results of this study, the variants of age and gender had no significant effects on the STT1 results in the Caspian horses. No significant difference was noted between the amount of tear production in the left and right eyes. CONCLUSIONS: Considering the importance of rapid diagnosis of dry eye syndrome and preventing its subsequent disorders such as Keratoconjunctivitis Sicca, the results of this study can be used as the reference value in the future to measure the amount of moisture of caspian horses of the Caspian horse.

BACKGROUND: Probiotics and prebiotics are the most important bioactive compounds for aquatic health. OBJECTIVES: In this study, the effects of prebiotic (immunowall) and probiotic (primalac) were assessed on growth performance, survival, body composition, and blood biochemical parameters in the Caspian Sea common carp Cyprinus carpio fingerlings. METHODS: Juveniles (n = 100 per tank, 21 tanks) were distributed in four inclusion levels (each in three treatments) of 0, 0.05, 0.1 and 0.15% of immunowall and primalac inclusions for a period of 56 days. Growth, body composition, and hematological parameters have been evaluated in different inclusion levels at the end of culture period. RESULTS: The increment of body weight, specific growth rate, and feed conversion ratio in fish fed with diets containing 0.15% prebiotic and 0.1% probiotic improved considerably compared to other treatments. The survival rate of the juveniles was not significant between treatments, and the group fed with the pre- and probiotics revealed higher survivals. Protein content in the group fed with the pre- and probiotic showed significantly higher contents compared to the control group, and lipid content showed increasing trend in different inclusions. The red blood cells contents showed no differences between treatments; but the white blood cells contents revealed higher performances in the fish-fed probiotics compared to prebiotic and control groups. CONCLUSIONS: These results recommend the addition of 0.1 % immunowall and 0.15 % primalac in the diets of the juveniles in terms of growth, feeding, and hematological indicators in the Caspian carp.

BACKGROUND: Based on previous studies, aquaculture systems affect on flesh quality in cultured species. In biofloc system, as a modern and new aquaculture system, animals use microbial flocs as feed and it seem such flocs affect on bodycomposition. OBJECTIVES: The aim of this study was to evaluate growth and chemical, microbiological and sensory properties of common carp meat cultured in Biofloc system. METHODS: Three hundred healthy fingerlings were randomly distributed in 12 tanks (70 L) at a density of 8.3 kg m-3 and fed experimental treatments: commercial diet as a control and three biofloc treatments including sugar beet molasses biofloc (SBM+BFT), sugar biofloc (S+BFT) and corn starch biofloc (CS+BFT). Fish in BFT treatments were fed at 75% of the daily feeding rate of control. At the end of experiment, growth performance and survival investigated. In addition to evaluate cultured fish meat quality, sensory properties of raw fish (day 0), rigor mortis (3, 6 and 24 h after catch), bacterial count, pH, expressible moisture and TVN were also assessed during 16 days, (every 4 days). RESULTS: The results indicated that the lowest food conversion ratio (FCR) and highest condition factor was observed in fish fed BC which differed significantly from control (P<0.05). No significant difference among treatments was observed in rigor mortis and bacterial count (P>0.05). pH in carp flesh increased gradually during storage time (P<0.05), but at the end of the storage period no significant difference was found between the treatments (P>0.05). The lowest primary TVN was seen in BS treatment (9.0 ± 0.2 mg N/100g flesh) but in other treatments TVN was higher than 20 mg/ 100g flesh (P<0.05). CONCLUSIONS: Overall, based on the results of this study, biofloc cultured fish flesh had acceptable quality in comparison with control fish.

BACKGROUND: Staphylococcus aureus is one of the most important pathogenic bacteria for human that is easily transferred during slaughtering, processing, packaging, storage and handling of meat and meat products as a result of poor hygienic principles, and causes staphylococcal food poisoning. Objectives: The objective of this study was to evaluate the contamination of raw and cooked ground beef in retail shops of Mazandaran to S. aureus and also detection of enterotoxin-producing genes in the isolates. Methods: One-hundred fifty ground beef samples (95 raw and 65 cooked) were collected randomly from retail shops, 21 May-21 July 2017. S. aureus was counted via culturing on Baird Parker Agar medium. Detection of enterotoxins A-E and G, H, I and J producing genes was conducted applying real-time PCR technique. Results: 68% of samples showed S. aureus contamination. The average count in raw and cooked ground beef samples was 3.1×105 cfu/g and 5.7×103 cfu/g, respectively. From 92 S. aureus isolates, 23 isolates (25%) were carrying enterotoxin coding genes; amongst them 15 isolates (65.2%) were carrying just a single gene and the rest more than one gene. Two isolates carrying SEA+ SEC, two isolates SEA+SEE, one isolate SEA+SEG, one isolate SEC+SEI, one isolate SEA+SEC+SEG and one isolate SEE+SEG. Conclusions: These results show that enterotoxigenic S. aureus strains are present on considerable numbers in retail ground meat in Mazandaran.

BACKGROUND:  Considering the progressing tendency of administration of nanomaterials products in the world and their entrance to aquatic ecosystems, their toxicity assessment on the aquatic environment and proposing the biocompatible solutions in their production seems indispensable. OBJECTIVES: In this study, the toxicity of silver nanoparticles (AgNPs), chemical and biosynthetic forms were evaluated using the biomarker, artemia nauplii (Artemia fransiscana). METHODS: For toxicity assessment, the OECD standard method was used. The artemia nauplii were exposed to additive serial concentration of biosynthetic and chemical silver nanoparticles. For biosynthesis of silver nanoparticles, aqueous extracts of two species of marine macroalgae Ulva flexuosa (green algae) and Sargassum boveanum (brown algae) were used. Artemia nauplii mortality in the times of 12, 24, 36 and 48 hours after exposure to silver nanoparticles were recorded and analyzed via Probit software. RESULTS: Survey findings showed that not only the toxicity of these three types of silver nanoparticles on artemia nauplii increased in a dose- dependent manner, but also their toxicity increased along with duration of exposure time. The toxicity of these nanoparticles were significantly different (P<0.05). The 48 h LC50 value of chemical AgNPs in the artemia nauplii was 31.8 mg/l, while 48 h LC50 for biosynthesis AgNPs  produced by U. flexuosa, and S. boveanum were 366.96 and 141.16 mg/l respectively. CONCLUSIONS: Comparison of the toxicity of these three types of AgNPs on artemia nauplii showed that, the chemical form of AgNPs was more toxic (up to 10 times) than a biosynthetic form of AgNPs. Moreover, the source of biosynthesis of silver nanoparticles had a considerable impact on toxicity of final production, because a biosynthetic form of AgNPs produced by U. flexuosa was less toxic than the same form prepared from S. boveanum.

BACKGROUND: Probiotics have more functional effects on shrimp immunological                         parameters but there is less information on comparative effects of Commercial and Indigenous probiotics on post-larvae and larval stage of shrimp life. OBJECTIVES: This 60 day study was conducted to determine the effect of probiotic bacterium commercial and allochthonous (Bacillus subtilis and Bacillus licheniformis) on some of immune parameters and serum enzymes in the whiteleg shrimp (Litopenaeus vannamei). METHODS: Three experimental diets were supplemented with similar concentration of 1.5×106 Cfu/g by bacteria, commercial and allochthonous supplementation. Control  (without probiotic supplementation), D1 (commercial probiotic), D2 (commercial+allochthonous probiotic) and D3 (allochthonous probiotic) were used for the experiment. At the end of trial, to evaluate immune parameters, Shrimp hemolymph was collected by syringe into the ventral sinus of L. vannamei, transferred to a tube and allowed to anticoagulant. To investigate serum enzymes level, body shrimp were homogenized and extracts were analyzed biochemically. RESULTS: Total haemocyte count (THC), large granular cells (LGC), semi granular cells (SGC) and hyaline cells (HC) treated with commercial probiotics increased in comparison with control and significant difference was observed (P<0.05). Enzyme alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly decreased in the experimental groups compared with control (P<0.05). However, post-larvae enzyme alkaline phosphatase was not found to be significantly affected by probiotic supplementation (P>0.05). CONCLUSIONS: The probiotic Bacillus influenced the increase of the immune parameters haemolyph and decreased serum enzymes level and it is appropriate for supplementation in the diet of whiteleg shrimp post-larvae.