Mariola Bochniarz

Antimicrobial susceptibility of Prototheca zopfii isolated from bovine mastitis

Abstract The aim of the study was to evaluate the susceptibility of algae of the genus Prototheca to antifungal and antibacterial antibiotics. The study involved 27 isolates of Prototheca zopfii obtained from milk of mastitis-affected cows kept in a detached cowshed in the North-Eastern part of Poland. Analysis of P. zopfii susceptibility has demonstrated low effectiveness of both antifungal and antibacterial antibiotics. All algae isolated from milk were resistant to clotrimazole, fluconazole, econazole, flucytosine, cefoperazone, cephalexin, enrofloxacin, lincomycin, and oxytetracycline (100% of resistant isolates), as well as miconazole (92.6% of resistant isolates). Nystatin, ketoconazole, and amphotericin B showed the highest activity amongst the antifungal antibiotics (88.9% and 0.0%, 51.9% and 22.2%, 0.0% and 48.1% of susceptible and intermediate susceptible isolates, respectively). In the group of antibacterial antibiotics, the high activity against P. zopfii was observed only in the case of gentamicin, kanamycin (96.3% and 92.6% of susceptible isolates, respectively), and polymyxin B (59.3% of susceptible and 33.3% of intermediate susceptible isolates).

Milk and serum IL-4, IL-6, IL-10, and amyloid A concentrations in cows with subclinical mastitis caused by coagulase-negative staphylococci

The aim of the study was to evaluate the concentrations of cytokines IL-4, IL-6, and IL-10 and acute phase protein amyloid A in milk and in serum from cows with subclinical mastitis caused by coagulase-negative staphylococci and from healthy cows. The blood and milk samples were obtained from 35 midlactation, multiparous (between parities 2 and 4) Holstein-Friesian cows. In the milk samples from 20 cows with subclinical mastitis, the following species of Staphylococcus were detected: Staphylococcus xylosus (8 samples), Staphylococcus chromogenes (6 samples), Staphylococcus haemolyticus (2 samples), Staphylococcus simulans (2 samples), and Staphylococcus sciuri (2 samples). The results of the present study indicate that the level of IL-6 in cows suffering from subclinical mastitis tended to be high in both serum and milk (432.09 and 254.32 pg/mL) compared with the level in healthy cows (164.47 and 13.02 pg/mL, respectively). Amyloid A value also was significantly higher in milk of unhealthy cows compared with cows without subclinical mastitis (790.2 and 360.5 ng/mL). No significant differences were found in levels of amyloid A in serum of both tested groups of cows (2,680.0 and 2,720.0 ng/mL). In contrast, concentration of IL-4 was significantly lower both in serum and in milk of cows with staphylococcal mastitis (86.1 and 123.17 pg/mL) compared with control animals (413.5 and 670.2 pg/mL). The level of IL-10 also was significantly higher in milk of healthy cows than in infected cows (39.78 and 22.5 pg/mL); however, differences in serum levels of this cytokine between tested groups were significantly less important (220.6 and 175.1 pg/mL).

Outbreak of protothecal mastitis in a herd of dairy cows in Poland

Abstract The study was carried out in a herd of 280 dairy cows in the North-Eastern part of Poland in the summer of 2011. During the period of 5-6 months before the study, mastitis cases resistant to routine antibiotic therapy were observed in this herd. Bacteriological examination of 280 milk samples collected from 70 cows with clinical or subclinical forms of mastitis was performed. Diagnosis of mastitis was made on the basis of anamnesis, clinical examination of the udder, macroscopic evaluation of secretion, California mastitis test (CMT), and results of bacteriological examination of milk. Protothecal mastitis was detected in 34 cows (12.6% of all cows in the herd). Algae belonging to Prototheca zopfii were isolated from 27 milk samples in pure cultures; in the remaining seven samples, mixed infections were identified (P. zopfii and Staphylococcus sp.). The acute form accompanied by elevated body temperature (40 C), pain and hot oedema of the udder, loss of appetite, and reluctance to move were observed in two cows immediately after delivery. The similar symptoms were also noted in three cows with mixed infections. The chronic form of protothecal mastitis was characterised by pasty oedema in the udder of slight painfulness and hard tissue consistency, as well as markedly reduced milk secretion. The macro- and microscopic changes in the mammary tissue was indicative of chronic, fusing microgranulomatous interstitial mastitis protothecosa.

Effect of Uterine Inflammatory Status as well as Calcium and Magnesium Concentrations on the Uterine Involution Process in Dairy Cows

Abstract The aim of the study was a comparative analysis of uterine horn diameter, calcium and magnesium concentrations in blood serum and uterine washings in cows both with and without endometritis. The study was performed on 28 cows at 5, 22 and 42 DP (day post partum), of which 14 cows had been diagnosed with endometritis and the other 14 had no endometritis. The animals were selected based on clinical symptoms and cytological examination. Uterine horn diameter was determined in both examined groups of cows using an ultrasonographic device. The level of calcium and magnesium in the blood serum and uterine washings, and protein in uterine washings was determined using a BS-160 Mindray analyzer. Uterus diameter was similar in both examined groups of cows only at 5 DP, and on subsequent days of examination this parameter was higher in the endometritis group compared to the control (P<0.001). Calcium levels in the blood serum of cows with endometritis were lower than in cows without endometritis, both at 22 DP (P<0.001) and at 42 DP (P=0.004). The levels of calcium, magnesium and total proteins in uterine washings were higher in cows with endometritis compared to the group without endometritis, both at 22 and at 42 DPP (P<0.001). The results of this study confirm that the process of uterine involution is slower in cows with endometritis compared to cows without endometritis, and the myometrium of inflamed uterus does not utilize sufficient amounts of calcium and magnesium, which means that the concentrations of these elements in uterine fluid are higher than in cows without endometritis.

The influence of the duration of the expulsive stage of parturition on the occurrence of postpartum oxidative stress in sows with uncomplicated, spontaneous farrowings.

The aim of the study was to determine the influence of the duration of the expulsive stage of parturition on the occurrence of postpartum oxidative stress in sows with uncomplicated, spontaneous farrowings. Twenty-five pregnant gilts were divided into three groups on the basis of duration of the expulsive stage of farrowing: (I) duration of the expulsive stage was below 3 hours; (II) duration of the expulsive stage ranged from 3 to 6 hours; (III) duration of the expulsive stage was longer than 6 hours. Blood samples were collected at 24 to 48 hours before and 24 hours after parturition. As indicators of alterations in the redox state, we quantified the enzymatic activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT), as well as the blood levels of glutathione (GSH), thiobarbituric acid reactive substances (TBARS), and sulfhydryl groups (SH groups). In group III, it was found that erythrocyte activity of CAT (63.89 ± 6.70 vs. 53.18 ± 2.32 U/g Hb), as well as plasma GSH concentration (0.088 ± 0.020 vs. 0.045 ± 0.024 mmol/g protein) and SH groups content (5.045 ± 1.256 vs. 3.383 ± 0.430 μmol/g protein) decreased significantly (P < 0.05) at 24 hours after parturition, compared with their values during the last 48 hours before parturition. The concentration of TBARS increased not significantly, although markedly at 24 hours postpartum in group III (0.124 ± 0.014 vs. 0.153 ± 0.031 μmol/g protein). The results indicate that uncomplicated, spontaneous parturition can lead to the occurrence of oxidative stress during the early postparturient period in sows, the intensity of which is related to the duration of the expulsive stage.

Acute-phase inter-alpha-trypsin inhibitor heavy chain 4 levels in serum and milk of cows with subclinical mastitis caused by Streptococcus species and coagulase-negative Staphylococcus species

The aim of the study was to investigate the concentrations of acute-phase inter-α-trypsin inhibitor heavy chain 4 (ITIH4) in serum and milk of cows with subclinical mastitis caused by Streptococcus spp. (STR) and coagulase-negative Staphylococcus spp. (CNS) and healthy cows. The blood and milk samples were obtained from 60 mid-lactation, multiparous Holstein-Friesian cows from 7 herds in the Lublin region of Poland. In the milk samples from 40 cows with subclinical mastitis, Streptococcus spp. and CNS were isolated. The ITIH4 was significantly higher in serum of cows with subclinical mastitis caused both by STR and CNS compared with healthy cows. One hundred percent of animals infected with Streptococcus spp. and 89% of animals infected with Staphylococcus spp. showed ITIH4 concentration in sera higher than 0.5 mg/mL. The concentration of ITIH4 in milk also was significantly higher in cows with subclinical mastitis caused by Streptococcus spp. and Staphylococcus spp. compared with the control group. Seventy percent of cows infected by STR and CNS showed ITIH4 concentration in milk higher than 2.5 μg/mL. Milk ITIH4 concentration higher than 5 µg/mL was found in 55% of animals infected with Streptococcus spp. and in 40% of animals infected with Staphylococcus spp. No statistically significant differences were observed in ITIH4 concentrations both in serum and in milk between the studied unhealthy animal groups. These results suggest that ITIH4 may be used in the future as a novel diagnostic marker in serum and in milk of subclinical mastitis in cows.

CharaCteristiCs of StaphylococcuS xyloSuS isolated from subCliniCal mastitis in Cows

Abstract The aim of the present study was to determine virulence factors and antibiotic susceptibility of Staphylococcus xylosus isolated from subclinical mastitis in cows. The material consisted of 42 isolates of S. xylosus obtained from 276 samples of milk collected from cows with subclinical mastitis. The isolates were obtained from the udder secretions of 33 cows from farms in the Lublin region (Poland). S. xylosus was found in 15.2% of tested milk samples. The study did not reveal any macroscopic changes in the milk or symptoms in the cow’s body. The number of somatic cells in milk samples ranged from 245,000 to 416,000/ml of milk (on average 268,000/ml of milk). The ability to produce slime was observed in 42.9% of S. xylosus isolates. None of the tested isolates demonstrated the ability to produce protease or cause haemolysis. Five isolates of S. xylosus (11.9%) were classified to the methicillin-resistant group. The mecA gene was not found in any of these isolates. The enzyme β-lactamase was detected in 28.6% of S. xylosus isolates. The highest efficacy against S. xylosus was demonstrated for cephalosporin antibiotics: cefacetrile and cefoperazone (80.1% and 76.2% of susceptible isolates of S. xylosus, respectively). A significant quantity of isolates was resistant to streptomycin, linkomycin, penicillin and neomycin (approximately 10% of susceptible isolates of S. xylosus).