Iranian Journal of Veterinary Research
Volume:23 Issue: 2, Spring 2022

The quality of colostrum is affected by IgG level and microbial load.

The quality of colostrum used in feeding dairy calves and passive immunity transfer in selected dairy farms in Fars province, Iran was investigated.

A total of 75 colostrum and neonatal blood samples were collected from 11 herds. The immunological quality of colostrum was assessed using a Brix digital refractometer. The bacteriological quality was assessed by performing total plate count (TPC), total coliform count (TCC), spore-former count, fungi count, and species-specific PCR assay to detect some bacterial species.

The mean Brix of colostrum samples was 25.4% and 72% of the samples had a Brix score ≥22%. The mean serum Brix and the prevalence of failure of passive transfer (FPT) were 10% and 4%, respectively. The mean TPC, TCC, spore-former count, and fungi count were 3.6 × 105, 2.8 × 104, 3.2 × 104, and 1.1 × 104 CFU/ml, respectively. The results showed that 50, 5.9, and 4% of colostrum samples were positive for Staphylococcus spp., Salmonella spp. and Maycobacterium paratuberculosis, respectively. There was no evidence of contamination with Brucella spp., Corynebacterium bovis and Mycoplasma bovis.

Considering all colostrum quality indicators comprehensively, only 37.3% of the studied samples met the industry standard. A large number of calves were at risk of receiving poor quality colostrum, especially in terms of microbial contamination. Further researches are needed to evaluate the colostrum management and the effect of bacterial contamination of colostrum on the health of neonate calves in this region.

Salmonellosis is one of the most important zoonotic diseases in humans and animals worldwide.

The main objective of this study was to report serovars, clonal relatedness, and antimicrobial resistance of Salmonella strains isolated from human, different animal hosts including pigeons, broilers, cattle, camel, parrots, and hamsters in different regions of Iran.

Twenty-four Salmonella isolates were confirmed at the genus level by biochemical tests and polymerase chain reaction (PCR) by showing the presence of invA gene. Serovars were determined and their clonal relatedness was assessed by RAPD-PCR and antibiotic resistance profiles.

Overall, Salmonella Typhimurium was the most prevalent serovar (45.8%, 11/24), which was recovered from humans, pigeons, and camels. Salmonella Enteritidis (29.2%, 7/24) was the second common serovar that was recovered from cattle, broilers, humans, and hamsters. Salmonella Infantis (12.5%, 3/24) belonged only to broiler sources, and Salmonella Seftenberg (12.5%, 3/24) was isolated from eggs and a parrot. The major RAPD pattern was VI (33.3%) in which the two S. Typhimurium isolates (belonged to humans and pigeons) exhibited similarity in both RAPD pattern and resistance profile. Antimicrobial susceptibility test showed full resistance to tylosin and erythromycin (100%, 24/24). All isolates (100%, 24/24) were susceptible to ceftriaxone, cefixime, and gentamicin. In total, 75% of the isolates were multi-drug resistant (MDR) and revealed 15 different antimicrobial resistance profiles (R-type).

This study supports the potential transmission of Salmonella serovars via animal contacts. Thus, it is necessary to establish a national systematic monitoring program with one health approach for controlling Salmonella infections.

Lipid mobilization increases significantly in cows around the time of calving; a correlation between excessive blood NEFA concentrations, oxidative stress, and impaired health status in transition dairy cattle was observed.

The relationship between serum thyroxin (T4) values and energy indices and lipid profile in all cows, non-fat cows (NFCs), fat cows (FCs), healthy, and diseased animals were estimated in the present study.

Blood samples were obtained from fifty multiparous cows on -14, +10, +20, and +30 days relative to parturition. They had similar diets and were kept under the same management conditions.

NEFA and BHBA values increased significantly on the 10th day of calving. Inversely, glucose, T4, triglyceride, LDL-C, and VLDL-C decreased significantly ten days after calving. There was a significant negative correlation between serum T4 and NEFA for all cows and FCs. Serum T4 and BHBA values had a significant negative correlation in NFCs, FCs, healthy, and diseased cows. In addition, serum T4 and fructosamine had a significant negative relationship in FCs and a significant positive correlation in diseased cows. Serum T4 values had a significant negative correlation with cholesterol, HDL-C, and a positive correlation with triglyceride and VLDL-C for all cows, NFCs, FCs, and healthy cows.

The data emphasized the effects of negative energy balance during the transition period on serum lipids profile and thyroid function. In addition, the correlation between T4 and energy and lipids indices may indicate a possible effect of health and body condition status on thyroid responses.

Listeriosis is a zoonotic disease of humans, animals, birds, fish, and crustaceans worldwide. Domestic animals, especially ruminants, are more susceptible to listeriosis. This infectious disease is caused by Listeria monocytogenes, an intracellular bacterium that can cross blood-brain, placental and intestinal barriers. In Pakistan, the incidence and reliable diagnostic tools for the L. monocytogenes are unidentified in Nili-Ravi buffaloes.

This study was designed to inspect listeriosis in buffaloes through molecular techniques and haemato-biochemical analyses.

A total of 230 samples (115 milk and 115 faecal samples) were collected from symptomatic listeriosis cases in Nili-Ravi buffaloes of 3 geographical districts (Rawalpindi, Faisalabad, and Muzaffargarh) Punjab, Pakistan. These samples were processed for DNA extraction using commercialized kits, and L. monocytogenes was confirmed by conventional PCR.

The results revealed that 6.08% and 4.34% of the isolates from milk and faecal samples were found positive for L. monocytogenes, respectively. The phylogenetic analysis of these isolates showed 97-100% similarity to isolates from the USA, Switzerland, Japan, and India. The accession numbers on NCBI GenBank appeared as HF558398 (Switzerland), KP965732 (India), EU372032 (USA), and LC259850 (Japan). Haemato-biochemical examinations showed that the values of WBCs, plasma fibrinogen, ALT, and AST significantly increased (P<0.05) in diseased buffaloes compared to healthy ones.

The occurrence of listeriosis in buffaloes urges continuous monitoring and surveillance to prevent this emerging disease in Pakistan.

Campylobacter species are the zoonotic bacteria and the most common cause of foodborne gastroenteritis around the world. The link between human campylobacteriosis and infected poultry consumption has been well established.

In this study, we aimed to isolate Campylobacter spp. from chicken and characterize them with molecular methods.

Totally, 241 chicken caecal mucosal scrapings were collected from five districts of Tamil Nadu. Bacterial isolation was done by plating on blood-free Campylobacter selective medium with supplements. Campylobacter species were identified by multiplex PCR and Campylobacter coli isolates were tested for 11 virulence genes by PCR. C. coli isolates were typed based on seven housekeeping genes multilocus sequence typing (MLST) scheme. The antimicrobial susceptibility was determined by a microdilution resazurin assay.

The prevalence of C. coli and C. jejuni were 14.94% (36/241), and 3.32% (8/241), respectively. The virulence genes flaA, flaB, cadF, cdtA, cdtB, cdtC, ciaB, and ceuE were present in all 36 C. coli isolates, pldA and racR genes were present in 58.33% (21/36), and 16.67% (6/36) of the isolates, respectively, and dnaJ was present in only one isolate. Two novel sequence types (ST-10872, ST-11031) were found in this study. Though different STs were identified, all the STs belonged to the same clonal complex of ST-828. All 14 C. coli isolates showed 100% resistance to nalidixic acid, and higher resistance to tetracycline (92.8%), erythromycin (71.4%), clindamycin (71.4%), and azithromycin (64.2%) was noticed. All C. coli isolates were sensitive to chloramphenicol, and higher sensitivity to ciprofloxacin (78.5%), and gentamicin (71.4%) was observed.

The present study demonstrated that C. coli is more prevalent in broilers than C. jejuni in Tamil Nadu. The presence of C. jejuni and C. coli in chicken caecal samples from the slaughterhouse are indicative of the possibility of public health hazards.

Bedding material must absorb moisture, reduce impacts, and allow chicken to express their natural behavior reducing the occurrence of injuries in the footpad and joints, and improving carcass quality and performance.

This study evaluated different bedding materials with different levels of inclusion of dried grass (Zoysia japonica) on the development of lesions in the locomotor system of broiler chickens.

One thousand eight-day-old male chicks of the Cobb 500® were distributed in a completely randomized design with a 3 × 2 factorial scheme: three levels of grass inclusion and two bedding materials (100% wood shavings; 100% rice husks; 25% grass and 75% wood shavings; 25% grass and 75% rice husks; 50% grass and 50% wood shavings; 50% grass and 50% rice husks). The birds at 21, 28, 35, and 42 days of age were evaluated for pododermatitis. Ten birds from each repetition were identified and evaluated weekly from 21 to 42 days for Gait score, latency to lie and leg angle (valgus and varus). At 43 days of age, 60 birds of each treatment were slaughtered and evaluated for femoral degeneration and tibial dyschondroplasia.

Different litter compositions did not affect the incidence of lameness, tibial dyschondroplasia and spondylolisthesis. Pododermatitis scores increased after 28 days when including 50% of grass.

Age contributes more to the development of locomotion injuries than does bedding material. It is recommended to use inclusions of dried grass only as bedding for young broilers.

Using unauthorized tissues in sausage is a common food adulteration in some parts of the world.

This study was designed to compare the accuracy of histochemical and immunohistochemical techniques for the detection of lung tissue in cooked sausage samples.

Samples with different levels of sheep lung tissues (1, 2.5, and 5%) and a control group were prepared and stained histochemically using H&E, Masson trichrome, and Periodic Acid-Schiff (PAS) stainings, and immunohistochemically using two different commercially-available antibodies of TTF1 Pan-cytokeratin.

The highest positive results of lung tissue detection were achieved in sausage samples stained with anti-TTF1 immunohistochemical staining method. Both anti-TTF1 and anti-pan-cytokeratin immunohistochemical techniques detected all contaminated sausage samples treated with 50 g/kg lung tissues. Anti-TTF1 staining method had the highest odds ratio (7.4), followed by anti-pan-cytokeratin method (6.0). Reversely, PAS staining method had the lowest odds ratio (0.21), followed by Masson trichrome method (1.7). Additionally, anti-TTF1 method had the highest (1.8-31.0) confidence intervale (95%), while PAS had the lowest (0.02-2.1). Totally, the odds ratio of lung tissue detected by immunohistochemical methods were higher than those detected by histochemical staining.

This is the first report on the comparison of histochemical and immunohistochemical techniques for lung tissue detection in cooked sausage. Anti-TTF1 immunohistochemical staining proved to be the most useful technique for the detection of unauthorized lung tissue in cooked sausages.

Consumption of contaminated eggs with Salmonella enterica serotype Enteritidis (SE) cause gastroenteritis in human.

The present study examined the effect of probiotic and prebiotic compared to antibiotic on the colonization of SE in the ceca, and the quantity and quality of produced eggs in the laying hens challenged with SE.

One hundred Hy-Line W-36 laying hens with 44-week-olds were studied for 13 weeks in a randomized complete block design containing five treatments and four replicates with five birds in each replicate. Treatments included: negative control, positive control, and antibiotic: diets containing antibiotic (Oxytetracycline 0.15 g/kg diet), probiotic (Bactocell® 0.1 g/kg diet), and prebiotic (Diamond V Original XPCTM 1.25 g/kg diet). All experimental groups except negative control were challenged with 1 ml of suspension solution containing 1 × 107 CFU/ml SE by oral gavage at the start of the ninth week of the experiment. Laying performance traits and cecal bacterial population were measured at the end of each week.

Probiotic and prebiotic showed a greater effect in the reduction of yolk cholesterol and blood cholesterol level before and after challenge with SE, respectively (P<0.05). In pre-challenge period, treatments had no effect on the cecal bacterial population; but after the challenge, three dietary supplements decreased the colonization of SE in the ceca of laying hens, and prebiotic showed more preventive effect (P<0.05).

The result of this study showed that the prebiotic can be effective in reducing and preventing SE colonization in laying hens and act as an alternative to antibiotics.

Difficult calving (dystocia) in buffalo cows is a major obstetrical problem which further leads to metritis complex, encompassing the retention of fetal membranes (RFM), puerperal metritis, endometritis and pyometra with impaired future fertility.

The current study aimed to evaluate the effect of the administration of intrauterine proteolytic enzymes on the expulsion of fetal membranes and postpartum fertility in dystociac buffaloes.

Proteolytic enzymes consisting of Trypsin (16 mg), Chymotrypsin (16 mg), and Papain (8 mg) were dissolved in 500 ml normal saline were administered  after 1 h of assisted delivery in dystociac buffaloes along with the conventional therapy.

The treated animals (n=15) expelled fetal membranes within a shorter period of time (P=0.043) compared to the control group (n=15) with none in the treatment group retaining it for more than 24 hours. Fewer (26.67 vs 73.33%; P=0.027) postpartum uterine infections developed in the treated animals compared to the control group. The interval between first postpartum estrus (P=0.067), service period (P=0.554), and open days (P=0.557) was shorter in the treatment group compared to the control group where postpartum anestrus developed less frequently (26.67 vs 66.67%; P=0.066) in the animals treated with enzymatic therapy. Systemic illness (neutrophillia) was reduced in the treatment group compared to the control on day 20 (64.55 ± 1.14% vs 70.23 ± 0.99%; P=0.001) and 45 (55.05 ± 1.63% vs 64.92 ± 1.45%; P<0.001) postpartum.

It is concluded that proteolytic enzymes therapy after assisted delivery in dystociac buffalo cows could help in the early expulsion of fetal membranes and reduce uterine infections with decreased neutrophils count.