Ayhan Bastan

Endometrial echotexture variables in postpartum cows with subclinical endometritis

The aim of this study was to evaluate endometrial echotexture changes on ultrasonographic digital images during subclinical endometritis using a computer-assisted image analysis program. Endometrial samples were collected from 140 Brown Swiss cows (days in milk = 35 ± 3) using a cytobrush method and classified as having a non-inflamed uterus (n = 66) and uterus with acute (n = 42), subacute (n = 21), and chronic (n = 11) inflammations. The mean cellular infiltration density was 0%, 31 ± 5%, 37 ± 6%, and 16 ± 8% for cows with non-inflamed uterus and cows with acute, subacute, and chronic uterine inflammations (P < 0.0001). As the cell infiltration density increased, both cervical diameter and mean gray level did not change. There were a liner decrease in homogeneity and a linear increase in contrast in response to increased cellular infiltration density. The sensitivity and specificity were 79.73% and 46.97% for the homogeneity value and 59.46% and 69.70% for the contrast value, respectively. In conclusion, monitoring endometrial echotexture alterations, especially homogeneity and contrast, changed depending on the cellular density and inflammation status and may be potential diagnostic markers for subclinical endometritis in cows.

Endometrial echotexture parameters in Turkish Saanen Goats (Akkeci) during oestrus and early pregnancy.

This experiment was conducted to evaluate endometrial echotexture in oestrus and early pregnancy and its association with ovarian hormones and foetal count in goats. Akkeci goats (Saanen×Kilis crossbreed, n=40) were randomly divided into two groups. Ten does (NAT) were mated on natural oestrus and 30 does (SYN) were subjected to synchronisation-prior to mating. The uterus was scanned on the days of sponge insertion (d -14), sponge removal (d -2) and mating (d 0) as well as 17 (d 17) and 30 (d 30) days after mating. Mean gray level (MGL), homogeneity (HOM) and contrast (CON) values were calculated. Blood samples were collected on days ultrasonography was performed. Data were analyzed by Chi-square, ANOVA, regression tests. HOM value reached the highest level on the mating day and then continuously decreased (P<0.0001). Overall, HOM values were greater for SYN does than for NAT does after mating. CON values were virtually stable during the experimental period. MGL value fluctuated during the breeding period (P<0.03) at a similar fashion in NAT and SYN does. Foetal count was not correlated with plasma hormones and echotexture parameters. Plasma progesterone concentration was correlated with echotexture parameters (r=-0.28 for HOM; r=0.29 for CON; r=0.25 for MGL; P<0.05 for all) during post-mating. In conclusion, echotexture parameters changed during the breeding period, in association with plasma progesterone concentration. Future studies should test if the echotextural changes during embryonic fixation days can be used as a marker for early detection of pregnancy in does.

Nitric oxide concentrations in mammary quarters during heifer mastitis

The aim of this study was to evaluate nitric oxide (NOx) concentration in infected and non-infected mammary quarters of dairy heifers before and after calving. The relationship between bacterial species and NOx concentrations, as well as correlation between NOx concentrations and postpartum somatic cell count (SCC), was assessed. Coagulase-negative staphylococci, Staphylococcus aureus and Escherichia coli were the bacteria commonly isolated during the pre- and postpartum period. Infected quarters had greater NOx concentrations than non-infected quarters before (30.81 v. 22.83 μM/ml, P < 0.05) and after (9.56 v. 5.77 μM/ml, P < 0.0001) calving. It was determined that the interaction between sampling period and infectious status had no effect on NOx concentration (P < 0.16). Infected quarters had greater SCC (log(10)) than healthy quarters (4.95 v. 4.39; P < 0.0001). NOx concentrations, however, did not correlate with SCC (r = 0.02). In summary, changes in NOx concentration were mainly dependent on the infectious status of the quarters with variations among the bacterial species (P < 0.05).

Effectiveness of Dry Cow Therapy Comprising Antibiotic Treatment, Internal Teat Sealant, and α-Tocopherol Against New Intramammary Infections in Cows

Abstract The aim of this study was to evaluate the preventive effectiveness of dry cow therapy based on antibiotic, internal teat sealant, and α-tocopherol administered separately or in various combinations at drying-off The study was performed on 322 uninfected quarters of 95 cows originating from three dairy herds. The new intramammary infection rates after calving were measured to evaluate the effectiveness. The quarters were divided into six groups differing in treatment, namely: control group (group C, n = 40) and five treatment groups. Treatment groups were arranged as follows: group A (antibiotic alone, n = 81), group AS (antibiotic + sealant, n = 40), group AST (antibiotic + sealant + α-tocopherol, n = 40), group T (α-tocopherol alone, n = 40), group S (sealant alone, n = 81). New infection rate amounted to 47.5% in group C. The treatment in group AST significantly prevented from the occurrence of new intramammary infections (12.5%, P < 0.05), especially those caused by major pathogens. Antibiotic treatment alone (group A) did not prevent from new infections (34.6%, P > 0.05), although the use of the sealant alone (group S) decreased the risk of new infection (24.7%, P < 0.05). A decrease in new infection rate (25%, P < 0.05) was also observed in AS group treated with the combination of the sealant and antibiotic. α -tocopherol supplementation alone (group T) had no overall effect on new infections (35%, P > 0.05). Increased α-tocopherol level (P < 0.05) was detected after calving in the quarters from cows that received α-tocopherol injections. In conclusion, the combination of antibiotic, internal teat sealant, and α-tocopherol used in dry cow therapy showed a significantly better preventive effect against new intramammary infections, than the therapeutics administered separately.

Effects of blood ²-hydroxybutyric acid levels on the response to Ovsynch in primiparous cows

The aim of this study was to investigate the effects of low and moderate blood β-hydroxybutyric acid (BHBA) levels in primiparous cows during the early postpartum period on follicle development and pregnancy rate after the Ovsynch protocol. Holstein primiparous cows with low (n = 85) and moderate (n = 71) BHBA concentrations were used as experimental animals. At 78 weeks postpartum, blood samples were collected and the Ovsynch protocol was performed on the same day. Ultrasonographic examination was performed to determine the dominant follicle (DF) diameter and presence of corpus luteum on the day of the first and second gonadotropin releasing hormone (GnRH1 and GnRH2) injections and prostaglandin F2 alpha (PGF2α) injection as well as 24 and 48 h after the GnRH1 and PGF2α injections. The ovulatory response to GnRH1 and pregnancy rate at day 30 and day 60 postinsemination were also evaluated. No significant differences were observed between groups in the DF diameter on the day of GnRH1 and PGF2α injections, and at 24 and 48 h after these injections, as well as in the ovulation and atresia response to GnRH1 (P > 0.05). Significant differences were observed between groups in DF diameter (low-BHBA group, 13.8 ± 0.2 mm; moderate-BHBA group, 13.2 ± 0.2 mm; P = 0.039) at the time of insemination, and in pregnancy rates at 30 days (low-BHBA group, 38.82%; moderate-BHBA group, 21.13%, P = 0.017) and 60 days after insemination (37.6 and 18.3%, respectively; P = 0.008). Our findings suggest that moderate blood levels of BHBA (0.80-1.19 mmol/L) in primiparous cows during the early postpartum period affect the response to the Ovsynch protocol.