نشریه علوم درمانگاهی دامپزشکی ایران
سال دوازدهم شماره 1 (پیاپی 19، بهار و تابستان 1397)

Mastitis is a common disease that decreases milk yield and quality in lactating cows. Because of higher treatment cost and higher culling rate, mastitis causes economical losses in the herd. So, earlier diagnose and treatment of mastitis with appropriate antibiotics could reduce treatment cost and culling rate in cow. Cows in this study were divided in 2 groups including cows with subacute clinical mastitis (n=25) and cows diagnosed with subclinical mastitis (n=49). The basis for clinical mastitis selection was the presence of abnormal milk in forms of clot and/or colorless or yellow watery discharge, and for subclinical mastitis was more than 4 × 106 somatic cells per milliliter of their affected quarters milk. In clinical cases, treatment was performed by daily administration of intramammary ointment Spectramast® LC (ceftiofur hydrochloride) for two to ultimately five times (in cases with abnormal secretions 48 hours after treatment commencement) (n=14) or Cobactan ® LC (cefquinome sulphate) after three to five consequent milking sessions (n=11). In Spectramast group treatment of subclinical mastitis was done by infusion of two syringes, 24 hours’ interval, while Cobactan group cows were treated by applying this ointment after three consecutive milking. Milk samples of both clinical and
subclinical cases were collected for bacterial culture and in the cases with subclinical mastitis, the sampling were done at the beginning of the study (pretreatment) as well as 14 days after the last treatment for evaluating of somatic cell changes. According to provided results, there was not any significant differences in the bacteriological cure rate of two antibiotic groups in both clinical and subclinical cases, clinical cure rate in clinical cases and SCC in subclinical cases

The subclinical mastitis can cause economical loss, therefore, access to the methods of prevention, control and reduction of mastitis, especially subclinical form, is so important and valuable. The aim of this study was to investigate the changes of adenosine deaminase enzyme activity in the cow milk with subclinical mastitis. Forty-six cows with subclinical mastitis that have taken positive results in the California mastitis test (CMT), without signs of illness, were considered as the treatment group. Ten cows that have taken negative results in the CMT, were considered as milk samples control group. Fat and protein levels of milk were measured as well as somatic cells count. Adenosines deaminases enzyme activities were also measured. The comparison of fat and protein in milk samples demonstrated no significant difference between healthy group, and the one with subclinical mastitis. The number of somatic cells in the cows with subclinical mastitis was significantly more than the control group. In the cows with subclinical mastitis, adenosine deaminase enzyme activity was significantly higher than the healthy cows. In general, adenosine deaminase enzyme activity can be used as a marker in diagnosis of subclinical mastitis.

Production of high quality eggs is an important subject in the egg industry and egg shell characters have roles on the egg quality. There are many factors that affect the egg shell quality such as: layers breed, age and diet, producing period, molting, infectious diseases and stresses, specially heat stress. In this study the effect of induced heat stress on some of eggs quality indices in white leghorn layers (Hyline W-36) were studied. Atotal 80 white leghorn hens were divided in two groups including control and heat stress groups in the same condition of egg and diet. Heat stress condition induced via increasing in bird's environment. Produced eggs from two groups were collected and 20 eggs were then chosen randomly for each group weekly. Then samples examined for eggs quality parameters. Results of this study showed a significance decrease (P 0.05) in the egg's weight, egg's size, egg's shell weight, egg's shell thickness in heat stress group compared to the control group. Also eggs shell's ash percent and eggs shell's calcium percent in heat stress group decreased significantly compared to the control group. In addition, comparison of eggs quality indices showed that negative effect of heat stress increased due to heat stress continuation. This study shows the effect of heat stress on eggs quality as a routine stress condition in commercial layer flocks.

The present study was designed to evaluate the effect of linolenic acid on the quality of rooster semen stored at 4˚ C. Semen was collected from ten roosters twice a week. Good quality ejaculates were pooled and then diluted, the semen was enriched with 0 (control), 40 (L40), 80 (L80) and 160 (L160) μM linoleate. Forward progressive motility (FPM), viability of spermatozoa, values of malondialdehyde (MDA) and total antioxidant capacity (TAC) in medium and spermatozoa were evaluated at 0, 24 and 48h. The result showed that, FPM was higher in L80 and L160 groups compared to control group at 24 and 48 h (P<0.05). Moreover, viability was greater in L80 and L160 groups in comparison with the control group at 48 h (P<0.05). Values of MDA were lower and values of TAC were greater in L80 and L160 groups in medium and spermatozoa compared to control group at 24 and 48 h (P<0.05). In conclusion, enrichment with of semen 80 and 160 μM linoleate could enhance quality of rooster semen stored at fridge temperature

A total of 192 one-day old Ross-308 broiler chickens were divided to 4 treatment groups of 48 chicks. Treatment groups were Control (Basal diet), vit-c (Basal diet+500mg/kg vit-c), Nano-Selenium (Basal diet+0.3mg/kg Nano-Se), and organic Selenium (Basal diet+0.3mg/kg Organic-Se). Chicks were raised until 35th day and growth performance was evaluated during the growing period. At day 35, 12 birds were selected in each group, bled and sacrificed to assess the relative weight of carcass, liver and spleen and to calculate the duodenal morphology and serum lipogenesis factors.Results showed that FCR of Nano-Selenium group was numerically better among groups but without significant differences (P>0.05) and relative carcass weight were also numerically higher in both vit-c and Nano-Selenium groups than that of others. The highest percent of liver weight were recorded in control group and had significant difference with vit-c group which could decrease relative liver weight (P<0.05). Moreover, spleen weight was increased in both Nano and organic Se groups. About morphological parameters of intestine, liberkuhn gland depth and villi height and surface of duodenum were enhanced in Nano-Selenium more than others and had significant differences with control group in all of the parameters (P<0.05). The differences of serum lipogenesis factors’ were not statistically significant but organic selenium had lower triglyceride and cholesterol levels than others. Meanwhile, PCV was decreased in Nano-Selenium groups. It could be concluded that Nano-Selenium is a better choice for improving performance parameters in broiler chickens than organic selenium and vit-c due to better impact on intestinal villi surface area and liberkun glands

Nowadays, despite remarkable advances in several areas of poultry production, unfortunately, coccidial infection causes huge annual economic losses, which can lead to disease in any age of poultry in the worldwide. Although, use of coccidiostats is one of common control practices, resistance to these drugs is growing. To evaluate and compare the effectiveness of common occidiostats versus non-use of these drugs, this study was undertaken by litter monitoring of a grandparent flock. Two nests of a house each 3100 day old grandparent chicks selected, raised under same management and diet conditions, except inclusion of coccidiostats. Entire rearing period, samples are taken from litter of each nests, regularly, analyzed by McMaster method to determine litter OPG, weekly. Mean body weight, egg  production, mortality and culls, and total feed consumption for both nesting birds recorded at the end of experiment. Results of this study reveals that, these parameters were the same in both groups. Although, some parameters were better in nonuse of coccidiostats birds due to an autoimmunity.

Avian Influenza disease has economic and public health significance. Avian influenza virus subtype H9N2 became endomic in Iran. Vaccination policy is used for control of it. Efficacy of avian influenza vaccine has an important role in control of disease, decreasing risk of infection and shedding of avian influenza virus, and then monitoring vaccine effectiveness is necessary. In this research, antibody responses to two commercial avian influenza vaccines were studied in broiler chickens. For this reason, 90 one-day-old commercial broiler chicks were divided to three groups. Group one and two received vaccines A and B respectively on day 14, and group three was not received vaccine. Serologic study with hemagglutination inhibition test (HI) was achieved weekly from day 14 until 49. The mean HI titers were significantly different (P<0.05) between group 1 and other groups three and four weeks post vaccination and also between vaccinated groups and non-vaccinated group five weeks post vaccination. Results indicated that both vaccines induced highest titers after 5 weeks of vaccination, although the titers were not induced protective immunity; also it was cleared that there was not interfering between maternal antibody and active immunity. In conclusion, with attention to this point that the two vaccines are commercial, the quality of them was regularly evaluated by producers, then, the most important reason for low quality of the vaccines probably is storage or transport of the vaccines in inappropriate temperature.

The purpose of this study was to investigate effect of secondary infection with avain influenza virus subtype H9N2 on tissue tropism and dissemination of ornithobacterium rhinotracheale (ORT) bacteria and H9N2 AI virus in different organs of specific pathogen free (SPF) chickens. Sixty, oneday- old SPF chicks ‘were randomly divided into three groups. They were kept in separate positive pressure isolators. On 21st day of study, the chicks in group 1 was inoculated intratracheally with 1×1010 CFU of ORT and three days later were adminstrated intraocularly with 1×106 EID50 of the H9N2, group 2 only inoculated with ORT bacteria. Group 3 as control was inoculated with PBS’ intraocularly. The samples from various tissues were collected at 6, 8, 10, 12, 14 and 16 days postinoculation (DPI). In group 1 chickens exhibited ruffled feathers, depression and reduced appetite, while in group 2 had minor clinical signs depression. The H9N2 AI virus was detected from lungs, trachea, bursa of fabricius, thymus, spleen and cecal tonsils of first group birds. The ORT was detected in the trachea, lung and liver of infected groups. The results showed that infected chickens with ORT under secondary infection by H9N2 AI virus cause exacerbate virulence and clinical signs and lesions
of ORT.

The effects of selenium supplements were investigated on blood glutathione peroxidase activity (GPX), selenium, copper, zinc, iron and weight gain. Twelve female Makuei breed, aged nearly 2 months old and weighed approximately 20 kg was studied for 63 days in 3 groups of control, nano selenium particles (NanoSe) and sodium selenite (NaSe). Mean concentrations of GPX, Cu and Fe were high in NanoSe but the differences were not significant. Among sampling time, it was significant constantly for GPX and Se, occasionally for Cu and Zn but not for weight gain. The percentages of weight gain based on birth weight in groups control, Nano SE were 34.2%, 38.9% and 36.3%, respectively, all were not different among groups and sampling times. The individual comparison of parameters in 40 lambs among groups showed differences for GPX, Se and Cu (P<0.01). Correlations were found between weight/Fe, weight/GPX weight/Se, Zn/Fe and GPX/Se in NanoSe. In conclusion, Se supplements increases GPX activity and Se in which the increases in NanoSe was regular and continues. Se supplements showed no negative effects on Cu, Zn and Fe but caused partially increase in weight gain. NanoSe revealed the correlations between weight gain, GPX, Fe and Se and was priority to NaSe. Thus, the effects of NanoSe in reduce the oxidative stress and increased weight gain was appropriate and probably reasonable option to NaSe administration in lambs.

White spot disease (WSD) is the most important viral diseases in shrimp Penaeidae family. However, no study has been done on wild Indian white shrimp brooder species (Fenneropenaeus indicus) in capture sites in Sistan-Baluchestan province, yet. The aim of this study was to evaluate the prevalence of WSSD in different seasons of captures in this province by molecular and pathologic methods. Out of 451 samples, 25 samples and 4 samples were found positive by molecular and
histopathology respectively. The rate of infection in the spring was significantly higher than in autumn. Prevalence rate in Pasabandar, Chabahar and Gwadar significantly increased, whereas no significant relationship was observed between gender and the size of the shrimp with white spot infection. Basophilic nuclear inclusion bodies were seen within the pillar cells in the secondary gill lamellae tissue and the severity of the infection was diagnosed grade two. High levels of pollution in the region of Gwadar due to infected shrimps in this region farms which entered the sea, On the other hand in Chabahar, one of the country's commercial ports, high prevalence of WSSD is due to ships that carry fouling organisms and discharge ballast water sail to these areas. It seems that attention to capturing sites and lack of collecting broodstock in the spring season be necessary to prevent the spread of disease

Twenty one pregnant Saanen goats were used and blood samples collected one week pre parturition, on parturition time, one week and two weeks post parturition. Biomarkers of oxidative stress including MDA, SOD, GPX, catalase and trace elements including Se, Zn, Cu, Fe and lipid profile and serum enzymes; AP, AST and ALT were measured. MDA decreased significantly on parturition time compared to one week pre parturition and increased one week post parturition again
and there was a significant decreasing two weeks after parturition rather than before (P<0.001). SOD, GPX and Catalase decreased after parturition (P<0.05). There were no significant changes in serum triglyceride and cholesterol at these 4 times but HDL increased significantly at one and two weeks after parturition in comparison with parturition time and one week before parturition (P<0.001). Se  decreased significantly on parturition time and in one week after it (P<0.05) but increased again in 2 weeks after parturition and reached to its serum level before parturition. Serum Zn and Cu concentration were significantly increased after parturition (P<0.05). Serum Fe decreased partly regular after parturition and its difference was significant two weeks after parturition in comparison to
prepartum level. A significantly decrease of Serum AP and AST was post parturition (P<0.001). This finding shows that Saanen goats undergo variation of oxidative stress with decreased of some trace elements after parturition

In this study, 180 chicks were divided into 4 groups in two distinct houses and chickens were reared until 22 days old in normal condition. From 22 to 42 days old, chickens in group 1 and 2 (in house 1) were reared in normal condition and chickens in group 3 and 4 (in house 2) were reared in 35 ˚C for 8 hours daily. Chickens in group 1 and 2 received vitamin C (100 mg/lit) from 22-42 days old. All chickens received ND and IB vaccines according to the routine vaccination program. Blood
samples were prepared at 42 days old for determination of heterophil to lymphocyte (H:L) ratio and assaying of serum IgG against ND vaccine. All chickens slaughtered at 42 days old. The trachea and nasal lavages were used for assaying of mucosal IgA against IB vaccine. The IgA assay was done by Elisa and specific IB antiglobulin. Results showed that acute heat stress can decrease weight gain, feed intake, serum HI titer, mucosal IgA titer, and increase H:L and Feed conversion rate (FCR). Supplement of vitamin C to drinking water in chickens reared under heat stress can increase weight gain, feed intake, serum HI titer, mucosal IgA titer and decrease H:L ratio and FCR. The present study demonstrated that acute heat stress had negative effects on humoral and mucosal immune responses against respiratory vaccines and administration of vitamin C provided a useful effect on mucosal and humoral immune response in chickens reared under heat stress.

Fetal sex determination in domestic animals has different research and commercial applications, especially in livestock industry. This technique has important economic value for horse breeders, especially in sales programs. Depending on the mare or stallion, the foal economic value is completely different and depends on its sex. The purpose of this study was identification of prenatal fetal sex using circulating cell free fetal DNA (ccffDNA) in mare during gestation by TSPY gene. The Real Time PCR technique was used by specific primers. Statistical Society contained 30 pregnant mares with 2-11 month of pregnancy. One stallion and one mare was selected as positive and negative control. For DNA extraction, we used the phenol-chloroform extraction method. Eighteen foals were male and twelve were male after parturition. In conclusion, our predicted fetal sex had the sensitivity, specificity and accuracy of 75%, 100% and 95%. Our results showed that the TSPY gene could be used for prenatal fetal sex determination by ccffDNA with high accuracy