Intrauterine bacterial findings in postpartum cows with retained fetal membranes

Quantifying known and emerging uterine pathogens, and evaluating their association with metritis and fever in dairy cows

Metritis is caused by polymicrobial infection; however, recent metagenomic work challenges the importance of known pathogens such as Escherichia coli and Trueperella pyogenes while identifying potential new pathogens such as Bacteroides pyogenes, Porphyromonas levii and Helcococcus ovis. This study aims to quantify known and emerging uterine pathogens, and to evaluate their association with metritis and fever in dairy cows. Metritis was diagnosed at 6 ± 2 days postpartum, a uterine swab was collected and rectal temperature was measured. 39 cows were classified into three groups: Healthy (n = 14), Metritis without fever (MNoFever; n = 12), and Metritis with fever (MFever; n = 13). Absolute copy number was determined for total bacteria and for 8 potentially pathogenic bacteria using droplet digital PCR. Both MNoFever and MFever cows had higher copy number of total bacteria, Fusobacterium necrophorum, Prevotella melaninogenica, Bacteroides pyogenes, Porphyromonas levii, and Helcococcus ovis than Healthy cows. MNoFever and MFever groups were similar. There was no difference among groups in copy number of Escherichia coli, Trueperella pyogenes, and Bacteroides heparinolyticus, and they all had low copy numbers. Our work confirms the importance of some bacteria identified by culture-based studies in the pathogenesis of metritis such as Fusobacterium necrophorum and Prevotella melaninogenica; however, it challenges the importance of others such as Escherichia coli and Trueperella pyogenes at the time of metritis diagnosis. Additionally, Bacteroides pyogenes, Porphyromonas levii, and Helcococcus ovis were recognized as emerging pathogens involved in the etiology of metritis. Furthermore, fever was not associated with the total bacterial load or specific bacteria.

Presence and localization of bacteria in the bovine endometrium postpartum using fluorescence in situ hybridization

The aim of this study was to investigate bacterial invasiveness of the bovine endometrium during the postpartum period. Fluorescence in situ hybridization was applied to endometrial biopsies using probes for Fusobacterium necrophorum, Porphyromonas levii, Trueperella pyogenes, Escherichia coli and a probe for bacteria in general (the overall domain Bacteria) to determine their tissue localization. Holstein cows were sampled at three time points postpartum (T1: 4-12 days postpartum, T2: 24-32 days postpartum and T3: 46-54 days postpartum). At T1, cows were clinically scored as having a uterine infection based on presence of a brownish, fetid vaginal discharge or as normal if having normal lochia. An endometrial biopsy was taken from all cows at T1 (n = 57). Endometrial biopsies were taken from the same cows at T2 and T3 if allowed by the size of the cervical canal and if the cow had not been inseminated. Fifty and 39 biopsies were obtained at T2 and T3, respectively. The biopsies were evaluated for inflammation and for presence and localization of bacteria. When analyzed by the probe for the entire domain Bacteria, bacteria were found in most biopsies irrespectively of time (T1: 79.0%, T2: 82.0%, T3: 89.7%). Fusobacterium necrophorum and Porphyromonas levii were often present in the endometrium at T1 (61.1% and 47.8%, respectively), but the prevalence decreased significantly over time. Trueperella pyogenes and Escherichia coli were less prevalent at T1 (8.8% and 10.5%, respectively) and their prevalence also decreased significantly over time. Fusobacterium necrophorum and Porphyromonas levii were often co-localized intraepithelially or in the lamina propria. Trueperella pyogenes and Escherichia coli were located only on the endometrial surface. Due to the high prevalence of tissue invasiveness, these findings emphasize the importance of Fusobacterium necrophorum and Porphyromonas levii in postpartum uterine disease of cattle and indicate that tissue invasiveness is an important aspect of the pathogenesis.

Bacterial invasion of the uterus and oviducts in bovine pyometra

Pyometra is a common disease of cattle that causes infertility and thereby financial losses to the cattle industry. Bacteria involved in the development and progression of pyometra have been investigated by microbial culture but their tissue invading abilities, which is an important aspect of bacterial pathogenicity and development of lesions, have not been investigated. Bacterial invasion of the uterus and oviducts was studied in 21 cows diagnosed with pyometra at the time of slaughter by applying fluorescence in situ hybridization using probes targeting 16S ribosomal RNA of Fusobacterium necrophorum, Porphyromonas levii, Trueperella pyogenes and the overall bacterial domain Bacteria. Fusobacterium necrophorum and P. levii were found to invade the endometrium, especially if the endometrium was ulcerated, and penetrated deep into the lamina propria. These species co-localized within the tissue thus indicating a synergism. Trueperella pyogenes did not invade the uterine tissue. In addition to endometrial lesions, most cows with pyometra also had salpingitis but without significant bacterial invasion of the oviductal wall.

A longitudinal cohort study of acute puerperal metritis cases in Swedish dairy cows

Background

Acute puerperal metritis affects cows during the early postpartum period and causes fever, fetid vaginal discharge and general depression. The disease is severe and treatment with antimicrobials is often required. This study followed 79 Swedish dairy cows with acute puerperal metritis with registered treatment and outcome in terms of recovery. Bacteria isolated from the uterus and their susceptibility to penicillin were studied. Clinical cases were assigned by participating practitioners who examined the cows, performed uterine swab sampling, decided treatment and provided information about cow health and calving conditions. Fertility and culling data were collected from the official Swedish milk and health recording scheme. Recovery from disease was defined in four levels; as a cow that survived 1 or 4 months, was inseminated and subsequently became pregnant. Intervals from dates of first and latest calving to insemination date were studied.

Results

The most common bacterial findings were a mixed culture of Escherichia coli and bacteria such as Gram positive cocci, Fusobacterium necrophorum, Clostridium spp. or Trueperella pyogenes. The Gram positive cocci, Pasteurella spp. and F. necrophorum were generally susceptible to penicillin. The majority of cows (70%) were treated with penicillin in accordance with the Swedish policy on treatment of metritis while 19% were treated with tetracycline and 8% were not treated with antimicrobials. Recovery rates were similar between treatments. Besides “calving to last insemination” interval (CLI) that was 5 days shorter than the national mean, fertility was slightly reduced compared to national means. “Calving to first insemination” interval (CFI) was 4 days longer than national mean and number of inseminations/cow increased from 1.9 to 2.1. Escherichia coli culture positive cows did not become pregnant to the same extent as cows without E. coli in the uterus (P = 0.046). Twin births resulted in a longer CFI (P = 0.034). The culling rate was generally high (42% within 300 days after occurrence of metritis), though death associated with acute disease was low (6%).

Conclusions

Escherichia coli was the most common bacterial pathogen isolated from cases of acute puerperal metritis in the present study. This bacterium is inherently resistant to penicillin, but although most cows were treated with penicillin, death due to acute disease was low and recovery and final fertility results were acceptable. In times of emerging antimicrobial resistance and demand for prudent antimicrobial use, we suggest that penicillin is a “good enough” choice if antimicrobial treatment of acute puerperal metritis is needed.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-016-0257-9) contains supplementary material, which is available to authorized users.

Uterine Microbiota Progression from Calving until Establishment of Metritis in Dairy Cows

The objective of this study was to evaluate the progression of the uterine microbiota from calving until establishment of metritis. Uterine swabs (n = 72) collected at 0, 2, and 6 ± 2 days postpartum (dpp) from 12 metritic and 12 healthy cows were used for metagenomic sequencing of the 16S rRNA gene on the Illumina MiSeq platform. A heat map showed that uterine microbiota was established at calving. The microbiota changed rapidly from 0 to 6 ± 2 dpp, with a decrease in the abundance of Proteobacteria and an increase in the abundance of Bacteroidetes and Fusobacteria, which were dominant in metritic cows. Uterine microbiota composition was shared; however, metritic and healthy cows could be discriminated using relative abundance of bacterial genera at 0, 2, and 6 ± 2 dpp. Bacteroides was the main genus associated with metritis because it was the only genus that showed significantly greater abundance in cows with metritis. As the abundance of Bacteroides organisms increased, the uterine discharge score, a measure of uterine health, worsened. Fusobacterium was also an important genus associated with metritis because Fusobacterium abundance increased as Bacteroides abundance increased and the uterine discharge score worsened as the abundance increased. The correlation with uterine discharge score and the correlation with Bacteroides or Fusobacterium showed that other bacteria, such as Helcoccocus, Filifactor, and Porphyromonas, were also associated with metritis. There were also bacteria associated with uterine health, such as "Candidatus Blochmannia," Escherichia, Sneathia, and Pedobacter.

Prophylaxis and therapeutic potential of ozone in buiatrics: Current knowledge

Ozone therapy has been in use since 1896 in the USA. As a highly reactive molecule, ozone may inactivate bacteria, viruses, fungi, yeasts and protozoans, stimulate the oxygen metabolism of tissue, treat diseases, activate the immune system, and exhibit strong analgesic activity. More recently, ozone has been used in veterinary medicine, particularly in buiatrics, but still insufficiently. Medical ozone therapy has shown effectiveness as an alternative to the use of antibiotics, which are restricted to clinical use and have been withdrawn from non-clinical use as in-feed growth promoters in animal production. This review is an overview of current knowledge regarding the preventive and therapeutic effects of ozone in ruminants for the treatment of puerperal diseases and improvement in their fertility. In particular, ozone preparations have been tested in the treatment of reproductive tract lesions, urovagina and pneumomovagina, metritis, endometritis, fetal membrane retention and mastitis, as well as in the functional restoration of endometrium in dairy cows and goats. In addition, the preventive use of the intrauterine application of ozone has been assessed in order to evaluate its effectiveness in improving reproductive efficiency in dairy cows. No adverse effects were observed in cows and goats treated with ozone preparations. Moreover, there is a lot of evidence indicating the advantages of ozone preparation therapy in comparison to the application of antibiotics. However, there are certain limitations on ozone use in veterinary medicine and buiatrics, such as inactivity against intracellular microbes and selective activity against the same bacterial species, as well as the induction of tissue inflammation through inappropriate application of the preparation.

The associations between postpartum serum haptoglobin concentration and metabolic status, calving difficulties, retained fetal membranes, and metritis

Measurement of serum haptoglobin (Hapto) concentrations results in only moderate reported specificity and sensitivity for the detection of metritic cows. The objective of this study was to evaluate associations between different variables and haptoglobin concentrations after calving. Parity, periparturient metabolic stress indicated by β-hydroxybutyric acid (BHBA) and nonesterified fatty acids (NEFA), calving difficulties, retained fetal membranes (RFM), and acute puerperal metritis (APM) were evaluated. A total of 443 Holstein Friesian cows were enrolled in this retrospective observational study. Acute puerperal metritis was diagnosed when a cow had fetid, reddish-brown, watery vaginal discharge in combination with rectal temperature ≥39.5°C. The retention of the fetal membranes has been defined as the failure to expel the fetal membranes within 12h after calving. Results of blood samples from 2 and 5 d in milk (DIM) were analyzed for Hapto, BHBA, and NEFA. Primiparous cows had a greater median Hapto concentration than multiparous cows at 5 DIM [primiparous: 2.25g/L, interquartile range (IQR) 1.45-2.50, n=146; multiparous: 1.13g/L, IQR 0.52-2.22, n=302; P<0.05]. Therefore, different Hapto thresholds based on references from literature for all cows (1.4g/L), primiparous cows (2.49g/L), and multiparous cows (1.4g/L) were used for further analysis. Periparturient metabolic stress indicated by elevated BHBA (≥1.2mmol/L) at 5 DIM was associated with elevated Hapto (odds ratio 2.39-2.87) regardless of parity. In contrast, elevated NEFA (≥0.6mmol/L) at 2 DIM was not a risk factor for elevated Hapto. Multiparous cows with assisted calving had a 2.46 times higher risk for elevated Hapto, whereas primiparous cows with assisted calving had no elevated risk for elevated Hapto at 5 DIM. Moreover, multiparous cows with RFM were 5.51 times more likely to have elevated Hapto at 5 DIM than cows without RFM. Acute puerperal metritis within the first 5 DIM was associated with elevated Hapto (odds ratio 2.74-5.01), regardless of parity. We speculate that the association of calving ease, RFM, and periparturient metabolic stress could explain the moderate sensitivity and specificity reported for the detection of metritic cows by measuring Hapto.

Pyogranulomatous pneumonia in goats caused by an undescribed Porphyromonas species, "Porphyromonas katsikii"

A yet-undescribed bacterial species, tentatively named "Porphyromonas katsikii," was isolated from individuals of a small goat herd with pyogranulomatous pneumonia during an outbreak of acute respiratory disease. The isolated bacteria grew in the form of black-pigmented colonies after 14 days of incubation under anaerobic conditions at 37°C on a tryptic soy blood agar medium. The bacteria were identified as a yet-undescribed Porphyromonas species by determination of the nucleotide sequence of the rrs 16S rRNA gene, and this species was tentatively named Porphyromonas katsikii. PCR amplification with specific primers for this yet-undescribed species revealed the presence of P. katsikii in the lung tissue of all affected animals, while no PCR signals were evidenced from the lungs of healthy goats or from goats with pasteurellosis caused by Mannheimia haemolytica. These data indicate P. katsikii as the causative agent of acute respiratory distress. P. katsikii is phylogenetically related to Porphyromonas somerae and Porphyromonas levii, which cause pathologies in humans and animals, respectively. P. katsikii was not detected by PCR from samples of the gingival pockets or of the faces of healthy goats.

Persistence of uterine bacterial infection, and its associations with endometritis and ovarian function in postpartum dairy cows

We investigated the relationship between the persistence of uterine bacterial infections with cytologically determined endometritis and ovarian function in 65 postpartum Holstein cows. Vaginal mucus discharges were collected, and endometrial smear samples (n = 130) were collected for cytological and bacteriological examinations from the cows at weeks 5 and 7 postpartum (pp). Blood samples were collected at weeks 3, 5 and 7 pp to determine plasma progesterone concentrations to monitor ovarian activity. According to the bacteriological examination, cows were classified into four groups. The first group (n = 32; 49%) comprised cows negative for bacteria at weeks 5 and 7 pp. The second group (n = 11; 17%) comprised cows with bacterial infections at week 5 pp but that were clear of infection at week 7 pp. The third group (n = 12; 19%) comprised cows without bacteria at week 5 pp but that acquired an infection by week 7 pp. The fourth group (n = 10; 15%) comprised cows with bacterial infections at weeks 5 and 7 pp (persistence of infection). A positive correlation (P < 0.001) was noted between the severity of cytologically determined endometritis, purulent vaginal discharge and the persistence of infection. Cows with persistent infections had a significantly (P < 0.01) prolonged luteal phase compared with cows without infection. In conclusion, the prevalence of cytologically determined endometritis and prolonged luteal phase were significantly increased in cows with persistent infections.

Uterine bacterial flora in postpartum Danish Holstein dairy cows determined using DNA-based fingerprinting: correlation to uterine condition and calving management

The overall aim of this study was to describe uterine bacterial flora during the postpartum period in Danish Holstein cows using the Terminal Restriction Fragment Length Polymorphism (T-RFLP) method. This method produces a pattern of nucleic acid fragments from the microorganisms present, reflecting the "fingerprint" of the actual microbial flora. As well as characterizing changes in flora with time from calving and between herds, data were examined for strong relations between uterine bacterial flora, calving management and uterine condition. In total 125 Holstein cows from five herds were included, and for each cow calving management was recorded. Cows were clinically examined on average 8 (range 0-19) and 28 (range 22-38) days after calving, and a uterine sample was taken for bacterial identification using T-RFLP. Milk samples were taken weekly for progesterone analysis. Bacteria were found in all cows at both examinations, and the flora was composed of many species, including species not traditionally reported to be present in the bovine uterus. The bacterial composition differed according to days from calving and herd. In all five herds Fusobacterium necrophorum, Pseudomonas/Acinetobacter and Bacteroides/Sphingobacterium/Prevotellaceae were among the most common at both examinations. In four herds there was a percentage decrease of F. necrophorum from first to second examination, and in all herds there was a percentage increase of Pseudomonas/Acinetobacter from first to second examination. No differences in bacterial flora were found between cows with different uterine scores, which were influenced by herd, calving difficulty and retained placenta.

Treatment of dairy cows with PGF2α or NSAID, in combination with antibiotics, in cases of postpartum uterine inflammation

Background

The aim of the study was to test the effect of two treatments in cases of acute puerperal metritis (APM) and clinical metritis (CM).

Methods

Cows with APM and CM (n = 40)) were matched according to plasma fibrinogen levels (Fb) into three groups. Two negative control groups D (n = 11) and E (n = 17) were composed of healthy cows. The proportion of animals with APM and CM was similar within the groups. Treatment was started on the 3rd day postpartum (PP). In group A (n = 15), intramuscular (i.m.) administration of ceftiofur was used for five days in combination with flunixin for three days. Group B (n = 15) received i.m. administration of ceftiofur for five days followed by two injections of prostaglandin F2_α, with an interval of 8 h, on the 8th day PP. Group C (n = 10) served as a control group with no treatment. The general health status, body temperature (BT) and vaginal discharge were evaluated daily. Endometrial biopsies for bacteriology were taken once a week for seven weeks PP. Blood samples for the analysis of acute phase proteins were collected once a week for six weeks PP. Samples for progesterone analysis were taken twice a week for seven weeks PP. Fertility performance data were recorded.

Results

The area under the curve of BT was higher in group B than in group D cows (P < 0.05). No differences were found for vaginal discharge. There were no differences in bacterial growth, start of ovarian activity or serum amyloid-A or fibrinogen levels among the groups. The haptoglobin concentration was higher in the first and second weeks PP in group B compared with the other groups (P < 0.05). The number of days open was higher in group A than in both groups B and D (P < 0.05). The pregnancy rate after the first two services was higher (P < 0.05) in groups B and D than in groups A and C. The number of services per pregnancy was lower in group B than in group C (P < 0.05).

Conclusions

Regardless of more severe uterine inflammation found in animals from group B, these cows showed the same fertility parameters as healthy animals.

Sensitivity to antibiotics of Arcanobacterium pyogenes and Escherichia coli from the uteri of cows with metritis/endometritis

The aim of the study was to determine the in vitro sensitivity of 161 Arcanobacterium pyogenes strains and 99 Escherichia coli strains isolated from the uteri of 312 cows with metritis/endometritis. Animals with pathological discharges were clinically diagnosed per rectum and per vaginum, and then swabs from the lumen of the uterus were aseptically collected. Bacteriological examination of swabs was according to commonly accepted procedures with the additional use of API tests. Sensitivity to antibiotics was tested by the disk diffusion method and performed in Mueller-Hinton agar. Arc. pyogenes strains were the most sensitive to amoxicillin/clavulanic acid (Amc) (97.3%), bacitracin (96.7%), ceftiofur (95.8%) and cephapirin (77.5%). E. coli strains were the most sensitive to norfloxacin (98.1%), marbofloxacin (95.8%), gentamycin (88%), Amc (80.7%) and ceftiofur (73.1%). Arc. pyogenes and E. coli were most resistant to oxytetracycline (63.7% and 31%, respectively).

Postpartum uterine infection in cattle

Postpartum uterine infections results from uterine contamination with bacteria during parturition. The prevalence of uterine infections varies considerably among studies. Uterine infection implies adherence of pathogenic organisms to the mucosa, colonization or penetration of the epithelium, and/or release of bacterial toxins that lead to establishment of uterine disease. The development of uterine disease depends on the immune response of the cow, as well as the species and number (load or challenge) of bacteria. The postpartum uterus has a disrupted surface epithelium in contact with fluid and tissue debris that can support bacterial growth. A variety of species of bacteria, both Gram-positive and Gram-negative aerobes and anaerobes, can be isolated from the early postpartum uterus. Most of these are environmental contaminants that are gradually eliminated during the first 6 weeks postpartum. A normal postpartum cow resolves uterine infection by rapid involution of the uterus and cervix, discharge of uterine content, and mobilization of natural host defenses, including mucus, antibodies and phagocytic cells. Clinical signs of uterine infection vary with the virulence of the causative organisms and the presence of factors that predispose to the disease. The treatment of endometritis and metritis in bovine should be directed towards improving fertility. The antibiotic should be active against the main uterine pathogens and should maintain its activity in the environment of the uterus. Also, should not inhibit the normal defense mechanisms and should be well tolerated and not induce irritation in the endometrium. Effective use of hormones in uterine infection requires knowledge of both normal reproductive endocrinology and the therapeutic characteristics of available hormonal preparations.

Bacterial isolates associated with dystocia and retained placenta in iraqi buffaloes

The present study was conducted on 50 recently calved Iraqi Buffalo cows. Depending on the kind of parturition, buffalo cows were divided into two main groups, the first group had normal unassisted parturition (NP) (26 animals) and the second group with certain periparturent complications (PPC) (24 animals). After 24 h of parturition, these two groups were further subdivided into two groups as cows expel their foetal membranes in <24 h postpartum and referred as non-retained placenta (NRP) while cows that did not expel their foetal membrane after 24 h referred as retained placenta (RP). Sampling for bacteriology, uterine discharge for polymorphonuclear cells per cent and blood samples for polymorphonuclear neutrophil (PMN) and the enzyme creatine kinase activity were performed at 6, 24 and 48 h postpartum. In PPC group, the most prevalent bacteria after 6 h of calving were Escherichia coli, beta-haemolytic Streptococci and Lactobacillus acidophilus. Total bacterial isolates in the uterus of buffaloes with RP in PPC group after 24 and 48 h were 129 and 183 respectively. Among the isolates, Archanobacterium pyogenes, Fusobacterium necrophorum, Prevotella melaninogenicus and Staphylococcus aureus were the most prevalent isolates after 48 h of RP buffaloes in PPC group. Polymorphonuclear neutrophil were significantly (p < 0.01) increased in the uterine discharge than in blood in buffaloes with RP in both PPC and NP groups. In conclusion, uterine contamination occurs as a result of postpartum ascending contamination by non-specific environmental organisms. The presence of Lactobacillus sp. in the uterus indicated a healthy uterus. Peripartum complications followed by retention of foetal membranes with the dominance of E. coli in the uterine lumen might favour the colonization of other bacteria including facultative anaerobic and strictly anaerobic in the uterine wall of buffaloes.

Ovine fetal necrobacillosis

The association of Fusobacterium necrophorum with late term abortion in sheep is reported. The bacterium was not culturable, but was identified in five cases by fluorescence in-situ hybridization (FISH) with an oligonucleotide probe specifically targeting 16S rRNA in F. necrophorum. Gross lesions were found in several tissues. Histologically, placental lesions were characterized by locally diffuse infiltration of neutrophils, closely associated with abundant small Gram-negative and FISH-positive rods, thrombosis and necrosis. Lesions in the fetal-maternal interface were multifocal and consisted of villous necrosis and suppurative inflammation. Spread to the fetus from the placenta appeared to occur in two ways. Some fetuses had multifocal necrotizing hepatitis consistent with haematogenous spread through the umbilical vein; further dissemination to other organs occurred. Transplacental spread and infection of the fetus through the amniotic fluid was characterized by development of multifocal suppurative dermatitis and suppurative bronchopneumonia. Localization of FISH-positive bacteria in necrotic lesions was restricted to the periphery. F. necrophorum would seem to have been unrecognized previously as a cause of abortion. The value of culture-independent diagnostic methods is emphasized.

Prevalence of aerobic and anaerobic uterine bacteria during peripartum period in normal and dystocia-affected buffaloes

Parturition complications predispose establishment of uterine infections, which in turn affect subsequent fertility. The aim of present study was to characterize and compare the type of bacterial flora prevalent within the uterine lumen of dystocia-affected buffaloes and compare them with the normally calving buffaloes. The study was conducted on 40 buffaloes; of which 10 calved normally (Group I) and 30 were treated for dystocia (Group II). Bacteriological examination was performed using uterine swabs, which were collected before delivery, immediately after delivery and day's 24-60 postpartum. A total of 30 uterine swabs from Group I and 79 swabs from Group II were collected, of which 19 (63.3%) and 71 (89.9%) yielded significant bacterial growth, respectively. A total of 205 isolates belonging to 10 different genera of bacteria were identified, 8 facultative anaerobes and 2 obligate anaerobes. In Group II, 91.6% of the bacteria positive swabs (n = 71) yielded mixed cultures, whereas the remainder being pure cultures. In contrast, 89.5% of the bacteria positive swabs of Group I (n = 19) yielded pure cultures. Mixed infections comprised mostly Arcanobacter (Actinomyces) pyogenes together with obligate anaerobes, Fusobacterium spp. and Bacteroides spp. In Group II, the frequency of incidental and coliform group bacteria was highest at the time of parturition, i.e., before and immediately after delivery, and decreased to nil during the 24-60-day postpartum period. However, in Group I, the incidental and coliform group of bacteria present at the time of parturition apparently persisted beyond the period when uterine involution is complete. The frequency of obligate anaerobes and A. pyogenes at the time of parturition was nil in the Group I while they predominated in dystocia-affected buffaloes (Group II). During the postpartum period of 24-60 days, the frequency of both obligate anaerobes and A. pyogenes increased significantly in Group II, whereas in Group I, only occasional isolates were obtained. To conclude, at the time of calving the prevalence of obligate anaerobes and A. pyogenes occurring in combination was highest in dystocia-affected buffaloes, and further increased in the postpartum period suggesting that these infections act synergistically.

Bovine necrotic vulvovaginitis associated with Porphyromonas levii

An outbreak of bovine necrotic vulvovaginitis associated with Porphyromonas levii, an emerging animal and human pathogen, affected 32 cows on a dairy farm in the northeast of Israel. Five animals had to be culled. This report appears to be the first that associates P. levii with bovine necrotic vulvovagnitis.

Assessment of early postpartum reproductive performance in two high producing Estonian dairy herds

Early postpartum (6 weeks) ovarian activity, hormonal profiles, uterine involution, uterine infections, serum electrolytes, glucose, milk acetoacetate and blood urea nitrogen (BUN) levels were studied in 2 Estonian high producing dairy herd with annual milk production of 7688 (Farm A) and 9425 (Farm B). From each farm 10 cows, with normal calving performance were used. Blood samples for the hormonal (PGF_2α-metabolite, progesterone) analyses were withdrawn. On day 25 PP blood serum samples were taken for the evaluation of metabolic/electrolyte status. On the same day estimation of milk acetoacetate values was done. The ultrasound (US) was started on day 7 PP and was performed every 3^rd day until the end of experiment. Uterine content, follicular activity and sizes of the largest follicle and corpus luteum were monitored and measured. Vaginal discharge and uterine tone were recorded during the rectal palpation. Each animal in the study was sampled for bacteriological examination using endometrial biopsies once a week. Two types of PGF_2α-metabolite patterns were detected: elevated levels during 14 days PP, then decline to the basal level and then a second small elevation at the time of final elimination of the bacteria from the uterus; or elevated levels during first 7 days PP, then decline to the basal level and a second small elevation before the final elimination of bacteria. Endometritis was diagnosed in 5 cows in farm A and in 3 cows in farm B respectively. In farm A, 5 cows out of 10 ovulated during experimental period and in 1 cow cystic ovaries were found. In farm B, 3 cows out of 10 ovulated. In 3 cows cystic ovaries were found. Altogether 40% of cows had their first ovulation during the experimental period. Three cows in farm A and 5 cows in farm B were totally bacteria negative during the experimental period. The most frequent bacteria found were A. pyogenes, Streptococcus spp., E. coli., F. necrophorum and Bacteroides spp. The highest incidence of bacteriological species was found during the first 3 weeks in both farms. All animals were free from bacteria after 5^th week PP in farm A and after 4^th week in farm B respectively. Serum electrolytes and glucose levels were found to be within the reference limits for the cows in both farms. No significant difference was found between farms (p > 0.05). Low phosphorus levels were found in both farms. Significant difference (p < 0.05) was found in BUN levels between farms. In both farms milk acetoacetate values were staying within the reference range given for the used test (<100 μmol/l). The uterine involution and bacterial elimination in the investigated cows could consider as normal but more profound metabolic studies could be needed to find reasons for later resumption of ovarian activity. Some recommendations to changing feeding regimes and strategies should also be given.

Influence of puerperal uterine infection on uterine involution and postpartum ovarian activity in dairy cows

This article presents the results of a clinical trial designed to study the effect of puerperal uterine infection on uterine involution and on ovarian activity in dairy cows, monitored twice weekly from parturition until the sixth week postpartum (wpp). Infection significantly retarded uterine involution assessed by the uterine body diameter and a score of intrauterine fluid volume (IUFV). By the sixth wpp, cows with normal puerperium (controls) and cows that showed mild puerperal endometritis had similar uterine body diameter and IUFV, indicating spontaneous recovery within the postpartum voluntary waiting period. However, in cows with severe puerperal endometritis, although uterine body diameter had regressed to pregravid size, IUFV remained significantly higher than in control and mild endometritis cows, indicating that chronic endometritis was established. The IUFV score was positively and significantly correlated with uterine swab bacterial growth density and allowed diagnosis of endometritis after the third wpp. Cows with mild or severe endometritis had a significantly higher prevalence and persistence of pathogenic bacteria (Escherichia coli, Actinomyces pyogenes, Gram-negative anaerobes - GNA) than controls. Actinomyces pyogenes was associated to GNA in 74% of isolations. Ovarian activity measured by ultrasound scanning of the ovaries and plasma progesterone (P4) concentrations was more abnormal (prolonged anoestrus, prolonged luteal phases and ovarian cysts) in cows with severe endometritis than in controls.

15-Ketodihydro-PGF(2 alpha), progesterone and uterine involution in primiparous cows with induced retained placenta and post-partal endometritis treated with oxytetracycline and flunixin

Retention of the foetal membranes (RFM) and post-partal endometritis are common problems in dairy cows. Among other things, the disease is characterized by a bacterial endometritis with aerobic as well as anaerobic bacteria. From an endocrine perspective, cows with RFM have high levels of 15-ketodihydro-PGF(2 alpha) (PG-metabolite) immediately after parturition but these levels fall rapidly within 2 weeks post-partum (early PG-metabolite elevation). After this decline, the PG-metabolite levels increase again and the levels (at this time of a lower magnitude) remain elevated during the period of uterine infection (late PG-metabolite elevation). The aim of this study was to investigate the PG-metabolite profiles in cows with retained placenta and post-partal endometritis treated with the prostaglandin synthesis inhibitor flunixin (F), either alone or in combination with oxytetracycline (T). The study was accomplished over 2 years with 12 primiparous cows in each experiment. As a model for RFM, preterm parturition was induced in late-pregnant heifers by injecting PGF(2 alpha) (25 mg i.m) twice with a 24 h interval. In each experiment, the cows were divided into four groups and treated with either T (10 mg/kg b.w. i.m. once daily), F (2.2 mg/kg b.w. p.o. twice per day), a combination of T and F (dosage, as above), or conservatively (0). The treatment periods lasted from day 11 to day 14 post-partum (pp) in experiment 1 (after placental shedding, groups T1, F1, TF1 and 0) and from day 3 to day 6 pp in experiment 2 (before placental shedding, groups T2, F2, TF2 and 0). Jugular vein blood samples were collected for analyses of PG-metabolite and flunixin. Uterine biopsies were collected twice weekly for investigation of endometrial microbiology. Rectal palpation and ultrasonographic examinations were performed three times per week for investigations of uterine and cervical involution and ovarian activity. No attempts were made to remove the placentas manually. The experiment lasted until day 56 pp. The induction of parturition was successful in all heifers and 22 of 24 animals had RFM. All RFM cows had bacterial endometritis, based on bacteriological examinations. Flunixin treatment (F1, TF1, F2 and TF2) suppressed PG-metabolite levels significantly (p=0.006) during the period of treatment in both experiments. However, the early flunixin treatment only suppressed PG synthesis partially. Late oxytetracycline treatment (T1) did not influence the PG-metabolite levels but oxytetracycline treatment (T2 and TF2) before placental shedding significantly altered the kinetics of the early PG-metabolite elevation compared with other treatments. Late PG-metabolite elevation was significantly correlated to duration of uterine infection and cervical involution. In conclusion, flunixin treatment of cows with retained placenta either before or after placental shedding suppresses prostaglandin synthesis. However, early treatment, when the release of prostaglandins is high, might need more intensive treatment in order to prevent the PG synthesis effectively. Oxytetracycline treatment during the period immediately after parturition before placental shedding might influence the PG-metabolite profile and suggests a bacteriological contribution to the high levels of PG-metabolite seen during the first 2 weeks pp in cows with retained placenta. In this study, a correlation between prostaglandin release, the final cervical involution and the end of infection was found. This suggests a link between uterine endocrinology, bacteriology and involution in cows with retained placenta.

Pharmacokinetics of ceftiofur in plasma and uterine secretions and tissues after subcutaneous postpartum administration in lactating dairy cows

A study was conducted to measure concentrations of potentially active ceftiofur derivatives, in plasma, in uterine tissues (endometrium and caruncles) and in uterine secretions at different time points after a single subcutaneous administration of ceftiofur hydrochloride (Excenel RTU Sterile Suspension) at the dose of 1 mg/kg body weight in Holstein-Friesian dairy cows. The animals (n=4) were injected within 24 h of calving, after expulsion of the foetal membranes. Plasma, lochial fluid, caruncles and endometrium were collected before ceftiofur hydrochloride administration and at 1, 2, 4, 8, 12 and 24 h after treatment. For each cow the concentrations of ceftiofur in the biological matrices were quantified using an high-performance liquid chromatography (HPLC) assay. The limit of quantification of the method was 0.1 microg/mL for plasma and 0.1 microg/g for lochial fluid, caruncles and endometrium. The concentrations of potentially active ceftiofur derivatives detected in plasma reached a maximum of 2.85 +/- 1.11 microg/mL at 2 h and decreased to 0.64 +/- 0.14 microg/mL at 24 h after administration. In lochial fluid, these concentrations reached a maximum of 0.97 +/- 0.25 microg/g at 4 h and decreased to 0.22 +/- 0.21 microg/g at 24 h after administration. In endometrium, these concentrations reached a maximum of 2.23 +/- 0.82 microg/g at 4 h and decreased to 0.56 +/- 0.14 microg/g at 24 h following the injection, whereas these levels in caruncles were 0.96 +/- 0.45 and 0.60 +/- 0.39 microg/g obtained at 8 and 24 h, respectively. At the dose of 1 mg/kg body weight in healthy dairy cows, subcutaneous administration of ceftiofur (as ceftiofur hydrochloride) after parturition results in concentrations of ceftiofur derivatives in uterine tissues and in lochial fluid that exceed the reported minimal inhibitory concentrations (MICs) for the common pathogens (Escherichia coli, Fusobacterium necrophorum, Bacteroides spp., and Arcanobacterium pyogenes) associated with acute puerperal metritis.

Clinical and bacteriological aspects on the use of oxytetracycline and flunixin in primiparous cows with induced retained placenta and post-partal endometritis

Retention of the fetal membranes and post-partal endometritis (RFM) are common problems in dairy cows. Treatment often includes manual removal of the placenta in combination with antibiotic treatment. Earlier studies have shown that cows with endometritis post-partum have a strong tendency to recover spontaneously. The present study focused on treatments of post-partal endometritis with the prostaglandin synthesis inhibitor, flunixin (F) either alone or combined with oxytetracycline (T). The study was conducted in two experiments, using 12 primiparous cows in each. As a model for RFM, premature parturition was induced in late pregnant heifers by injecting PGF2alpha (25 mg i.m.) twice with a 24 h interval. In each experiment the cows were set into four groups and treated with either T (10 mg/kg BW i.m. once daily), F (2.2 mg/kg BW p.o. twice daily), a combination of T and F (dosage, as above) or conservatively (group 0, no drugs). The treatment periods lasted from days 11-14 post-partum in experiment I (groups T1, F1, TF1 and 0) and from days 3-6 post-partum in experiment 2 (groups T2, F2, TF2 and 0). Jugular vein blood samples were collected for analyses of flunixin and total white blood cells. Uterine biopsies were collected twice weekly for investigation of endometrial microbiology. Rectal palpation and ultrasonographic examinations were performed three times weekly for investigations of uterine involution and ovarian activity. No attempts were made to remove the placentas manually. The experiment lasted until day 56 post-partum. The induction of parturition was successful in all heifers and 22 of 24 animals had RFM. All RFM cows had bacterial endometritis. The predominant bacteria were Escherichia coli alpha-haemolytic streptococci, Fusobacterium necrophorum, Arcanobacterium (Actinomyces) pyogenes, Bacteroides spp., Pasteurella spp. and Proteus spp. Fusobacterium necrophorum and A. pyogenes could be isolated for 3-5 weeks post-partum and E. coli Pasteurella and Proteus could be isolated for 2-3 weeks post-partum. Animals treated with tetracycline after placental shedding (T1 and TF1) had a more rapid recovery from infections with A. pyogenes and F. necrophorum than animals that were not treated with tetracycline. No other genera were affected. Antibiotic treatment before placental shedding (T2 and TF2) did not shorten the uterine infection but altered the bacterial flora, seen as an overgrowth of Proteus spp. (p < 0.05) and increased frequency of Pasteurella (p < 0.05). The alpha-haemolytic streptococci were less common in T2 and TF2 than in other groups (NS). Antibiotic treatment of cows before placental shedding (T2 or TF2, n = 6) postponed detachment of placenta compared to cows were no antibiotics were administered before placental shedding (T1, TF1, F1, F2 and 0, n = 16. 9.8 days pp (median) versus p = 0.004). Neither treatment shortened uterine involution. Flunixin treatments did not seem to influence recovery from infection or uterine involution. It was concluded that early oxytetracycline treatment of retained fetal membranes in the cow did not shorten the uterine involution or uterine infection but it did slow down the detachment process of the retained placenta. Oxytetracycline treatment after placental shedding might shorten the uterine infection but otherwise did not affect the clinical results. Flunixin treatment had no influence on the clinical outcome of the disease.

Pregnancy-specific protein B (bPSPB) and progesterone monitoring of post-partum dairy cows with placental retention

The relationship between placental retention, progesterone and pregnancy-specific protein B (bPSPB) was determined in 60 calving Holstein cows. The cows were divided into two groups with placental retention (WPR, n = 16) and no placental retention (NPR, n = 44). Every 4 days, until 60 days post-partum, blood samples were taken and the uteri were checked using ultrasonographv. The puerperal characteristics of NPR and WPR were as follows: mean days of abnormal vaginal discharge: 20.2+/-5 versus 35.6+/-7 (P < 0.01); mean intervals to uterine involution: 21.4+/-3.7 versus 27.6+/-7.6 days (P < 0.01); rate of endometritis: 25 versus 100% (P < 0.01). The mean numbers of oestrus cycles per cow were 1.75+/-0.5 versus 0.85-/+0.9 (P < 0.05) and the mean durations of the first oestrus cycle were 18+/-3.5 versus 16+/-2.1 days (P > 0.05). The mean intervals to first ovulation were 21.5+/-8.4 versus 35+/-19 days (P < 0.01). bPSPB blood concentrations were higher in the WPR group at calving with 955+/-170 versus 750+/-205 ng/ml (P < 0.01) and also during the first 32 days post-partum with 173.68+/-47.3 versus 131.0+/-29.2 ng/ml (P < 0.01). The mean bPSPB half-life was similar in the two groups: 6.9+/-2.5 versus 6.5+/-2.1 days (P > 0.05). In conclusion, it was found that placental retention was associated with a higher rate of endometritis, a lower number of cycles, longer interval to first post-partum ovulation and higher concentration of bPSPB at calving and during the post-partum period. The positive relationship between bPSPB concentrations and calf birth weight and their association with post-partum pathological events may be useful in monitoring animals presenting high concentrations at calving.

Influence of Escherichia coli and Arcanobacterium pyogenes isolated from bovine puerperal uteri on phenotypic and functional properties of neutrophils

When cows develop endometritis after birth, Escherichia coli and Arcanobacterium pyogenes are usually the most prominent bacteria present in bovine uterine lochial secretions. A. pyogenes alone is rarely found in the course of a disturbed puerperium. This was confirmed in this study, since average and high-grade uterine contaminations were always associated with the presence of both bacteria. The contamination grade was positively correlated with uterine polymorphonuclear granulocyte (PMN) numbers and negatively correlated with blood PMN numbers. Whether E. coli and A. pyogenes affect the phenotype and function of bovine PMN in a similar or differential way was subject to in vitro studies. PMN were tested in the presence of washed bacterial fragments or culture supernatants taken as a source for soluble and/or secreted bacterial products. Fragments and soluble products differed only quantitatively in their effects on PMN. Usually, long-time exposure (24h) of PMN to fragments induced the strongest effects. Accelerated death of granulocytes was only moderately induced by both E. coli and A. pyogenes products. Both E. coli and A. pyogenes products induced the enhanced expression of a membrane molecule detected by mAb IL-A110 and of CD11b. Expression of other surface structures remained largely unchanged (MHC class I, CD11c). Functional parameters of PMN (phagocytosis; generation of reactive oxygen species, ROS; antibody-independent cellular cytotoxicity, AICC) generally declined after pre-incubation for 24h with products of E. coli or A. pyogenes. Interestingly, soluble products of A. pyogenes stimulated the phagocytosis of PMN. However, co-incubation with E. coli products abrogated this stimulatory effect. The results supply evidence for similar modes of action of the gram-negative E. coli and the gram-positive A. pyogenes on bovine PMN. Alterations in PMN function and phenotype are mainly triggered by direct contact between bacterial fragments and PMN. Inhibition experiments with polymyxin B demonstrated that E. coli-mediated effects were not solely due to the action of lipopolysaccharide. The dominant functional depression of neutrophils by E. coli products strengthens the suggestion that the earlier appearance of E. coli in the uterus may support the co-infection of this organ by A. pyogenes at later times.

Relationship between intra-uterine bacterial contamination, endotoxin levels and the development of endometritis in postpartum cows with dystocia or retained placenta

A study was conducted to investigate the relationship between intra-uterine bacterial contamination, endotoxin levels and the development of endometritis in cows that experienced a dystocia or retained their placenta. Fifteen healthy cows, 31 cows with retained placenta (RP) and 13 cows that had dystocia were clinically examined 1 or 2 days after parturition when a uterine swab for bacteriological examination was taken. In addition, plasma and uterine lochia samples were collected to determine lipopolysaccharide (LPS) and the plasma IgG anti-LPS concentrations. Subsequently, 15 RP and 6 dystocia cows were initially left untreated and another uterine swab was collected at 2 and 4 wk postpartum. Immediately after calving, RP cows had significantly higher LPS levels in uterine lochia (average of 2.24 x 10(4) Endotoxin Units (EU)/mL) as compared to dystocia and healthy postpartum cows (average of 0.10 and 0.26 EU/mL, respectively). However, plasma LPS levels were below the detection limit (<0.036 EU/mL platelet-rich plasma) in all groups of cows. IgG anti-LPS levels in plasma were not significantly different between the 3 groups immediately postpartum (average of 26, 16 and 44 Median Units (MU)/mL) for healthy, dystocia and RP cows, respectively), but they were significantly lower when compared to plasma IgG anti-LPS levels of healthy cows at more than 2 months postpartum (mean 83 MU/mL). High LPS levels in lochia at 1 or 2 days postpartum were significantly related to abnormal cervical discharge, the presence of Escherichia coli, black pigmented gram-negative anaerobes and Clostridium spp. shortly after calving, and Arcanobacterium pyogenes and gram-negative anaerobes in the uterus at 14 days postpartum. These results suggest that the presence of E. coli and LPS (endotoxins) in lochia early postpartum favor the development of uterine infections by A. pyogenes and gram-negative anaerobes later postpartum. LPS were not observed in plasma, suggesting that either they are not absorbed into the blood, or they are efficiently detoxified by IgG anti-LPS or other detoxification mechanisms.

Clinical signs and hormonal changes in dairy heifers after induction of parturition with prostaglandin F2 alpha

Parturition was induced in 12 dairy heifers with prostaglandin (PG) F2 alpha about 2 weeks before the expected time of calving. Eight animals gave birth after two injections (group 1), three animals needed more than two injections (group 2) and one animal (cow no. 740) required one injection. All animals in groups 1 and 2 had retained foetal membranes and the time needed to induce parturition was 59 +/- 7 and 149 +/- 10 h, respectively. As cow no. 740 did not have retained foetal membranes and calved 24 h after one PGF2 alpha injection, it was excluded from the results. Udder distension and relaxation of the pelvic ligaments could predict the calving to within 12 h. Furthermore, the pre-calving drop of body temperature could predict the time of parturition to within 16 h. The total white blood cells and polymorphonuclear cells were at their highest values on the day preceding parturition whereas mononuclear cells had a tendency to increase 3 days after calving. Increased levels of haemoglobin were found at the time of parturition, whereas, plasma-calcium levels significantly decreased after parturition (P < 0.001). Progesterone levels markedly decreased after the first PGF2 alpha injection and reached 2 nmol/l at the time of parturition. Plasma levels of oestradiol-17 beta reached the peak at the time of parturition, whereas, the highest levels of the PGF2 alpha metabolite and cortisol were recorded 16 h after calving.

Uterine bacteriology, histology, resumption of ovarian activity and granulocyte function of the postpartum cow in different milking frequencies

The postpartum uterine bacteriology, histology, resumption of ovarian activity and polymorphonuclear granulocyte (PMN) number and function in 18 Swedish dairy cows were studied. Cows were milked either 2x (n = 9) or 3x per day (n = 9). Endometrial biopsy samples for bacteriological and histological investigations were collected during 8 weeks postpartum, starting within one week after calving. Milk samples for progesterone determination were collected twice a week until the cows had shown normal reproductive cyclicity. Blood samples for granulocyte function (phagocytic capacity and total number) were collected from each animal on the same days as when the biopsies were obtained. All animals in both groups were free from bacteria at the latest after 6 weeks post-partum and there was no difference regarding bacterial elimination and bacterial species between milking groups. No difference regarding uterine histology between milking groups was seen. In both groups, 8 cows had normal to slight infiltration of leukocytes in the endometrium at the end of sample collection. No changes in granulocyte function could be seen in the 2 milking groups. Resumption of ovarian activity was detected on day 45.6 +/- 9.3 (mean +/- SD) postpartum in the 2x milking group and 36.6 +/- 9.0 (mean +/- SD) post-partum in the 3x milking group (p = 0.05). Based on our findings, an increased milking frequency from 2 to 3 times a day did not influence the uterine function postpartum.

Induction of parturition with prostaglandin f2 alpha as a possible model to study impaired reproductive performance in the dairy cow

Parturitions were induced in five cows, 2 weeks before term using prostaglandin (PG) F(2alpha). Two i.m. injections were performed with an interval of 24 h. All cows calved within 5 days (average 2.7 days) after the first injection of PGF(2alpha). Out of five cows, four had retained fetal membranes (RFM). Each animal was sampled for bacteriological examination using uterine biopsies twice a week during 42 days postpartum (PP). Jugular vein blood samples were withdrawn for PGF(2alpha)-metabolite and progesterone analyses five times per day during the first week PP and eight times per 24 h during the 2nd and 3rd weeks PP. From the 4th week, the sampling interval was reduced back to five times per day. From the 5th week PP, the sampling was reduced to two times per day and sampling was terminated after day 46 PP. Only morning samples were used for progesterone analyses. From day 10 PP, ultrasonography (US) was performed every 3rd day until day 39 PP for detection of ovarian activity and follicular dynamics. The highest incidence of bacteriological species was found during the first 3 weeks PP. After the 5th week of collection, all animals were free from bacteria. The species of bacteria found were Arcanobacterium (Actinomyces) pyogenes, Escherichia coli, alpha-hemolytic streptococcae and Pasteurella multocida. Immediately after parturition, very high levels of the PG-metabolite were seen in all animals, with a sharp decrease to line of significance around days 9-12 PP. Small increases above the line of significance were detected up to day 27 PP in cows with RFM, and after that time the levels were considered to be at baseline. Low levels of progesterone were seen in four animals during the whole experimental time. In one animal, an increase was seen on day 43 PP, which was maintained until the end of the experimental period on day 46 PP. Based on US, follicular waves were detected in all animals during the experimental period. In three animals, three non-ovulatory follicular waves were detected and in two animals, four non-ovulatory follicular waves were detected during 39 days of ultrasound sessions. Based on progesterone levels, only one animal was considered to have ovulated around day 40 PP. Results from the present study indicate that reproductive performance of cows after PG-induced parturitions differs from those of spontaneous cases of RFM. Differences regarding the resumption of ovarian activity were also observed between previous studies of dexamethasone-induced parturitions and the present study.

Bacteriological and histological investigation of the postpartum bovine uterus in two Estonian dairy herds

Postpartum uterine infections, endometrial histology and resumption of ovarian activity in cows were studied in 2 Estonian dairy herds with different herd sizes, milk yields and management systems. Ten cows at Farm A and 5 cows at Farm B were studied in the experiment. All cows in the study had normal calving performance. Endometrial biopsies for bacteriological and histological examinations were collected once a week starting on the second week postpartum and continuing for 7 weeks postpartum. Milk progesterone samples were collected twice a week during the whole study period. In both herds, the uterine flora contained mainly facultative anaerobic bacteria (Streptococcus spp., E. coli, Staphylococcus spp., Proteus vulgaris). Among obligate anaerobic bacteria only Bacteroides spp. were found. After 7 weeks of collection at farm A, a bacterial uterine flora still persisted in 2 of the cows. At farm B, on the other hand, bacterial elimination was complete after 6 weeks. Presence of inflammatory cells in uterine histology specimens remained higher at the end of collection and resumption of ovarian activity was delayed at farm A. After 7 weeks postpartum, only 6 of the 10 cows at farm A had resumed ovarian cyclicity, while at farm B the first oestrous cycle had occurred in all cows. The study showed that differences regarding uterine infections and their clearance occurred between farms and, despite these differences, cows with normal calving performance will effectively recover without any treatment.

Prostaglandin F2 alpha and progesterone profiles in post-partum cows with short luteal phases

Sequential blood samples were collected at 3 h interval from 3 Swedish dairy cows starting from the day of first post-partum ovulation for 10 consecutive days to describe short luteal phases. All plasma samples were analysed for the concentrations of the main PGF2 alpha metabolite, 15-ketodihydro-PGF2 alpha, whereas levels of progesterone were monitored from all morning samples. The day of ovulation was judged when the largest follicle, being monitored by a real-time B mode ultrasound scanner, could not be detected at the next examination. A sustained rise above 0.5 nmol/l of progesterone level was taken as a clear-cut value between non-luteal and luteal phases. Luteal phases of less than 8 days were registered as a short luteal phase during which the cows showed a total of 8 to 11 significantly elevated levels of the prostaglandin metabolite. The number of the significant increases of the metabolite was calculated using a skewness method. Analysis of these significant increases showed the first 1 to 4 episodes without altering the concentrations of progesterone. This would suggest that the developing corpus luteum is refractory in the beginning and thus, to induce luteolysis several PGF 2 alpha releases are required. The magnitude of progesterone concentrations during the short luteal phase is lower than the following phases.

Diagnostic studies of abortion in Danish dairy herds

Diagnostic findings in 218 aborted bovine foetuses are reported. The materials were examined in a matched case-control study of 69 Danish dairy herds with a sudden increase in the number of abortions and a corresponding 69 control herds. Foetuses aborted during the subsequent 6-month period were examined to identify the cause of abortion if possible. A total of 186 specimens were submitted from case herds and 32 from control herds. A likely cause of abortion was diagnosed in 73 foetuses. The most common cause was bovine viral diarrhoea virus (BVDV: 13%) followed by Neospora caninum infection (10%), mycosis (5%) and Bacillus licheniformis infection (4%). Foetal and/or placental lesions were found in a further 27 cases. Only BVDV infection and neosporosis were diagnosed in more than one foetus per herd and only protozoal associated abortions occurred significantly more frequently in the case, rather than in the control, herds.

Intrauterine bacterial findings and hormonal profiles in post-partum cows with normal puerperium

The post-partum intrauterine bacterial flora, prostaglandin release, uterine involution and resumption of ovarian activity were studied in 9 Swedish dairy cows during the first 8-week period. Uterine involution was monitored by transrectal examinations of the reproductive tract 3 times weekly. Bacteriological examination was performed from twice weekly uterine biopsies. The main PGF2 alpha metabolite (15-ketodihydro-PGF2 alpha) was monitored from twice daily blood plasma samples, while morning samples were used for progesterone determinations. The cows were assigned to 2 groups: Group I (n = 7) with an uncomplicated puerperal period and Group II (n = 2) with signs of intrauterine infections. A total of 143 biopsies were collected, of which 129 (90.2%) were found to be bacteriologically negative. Thirteen (9.1%) of the remaining 14 biopsies were bacteriologically positive, while one (0.7%) was probably a contamination on a single occasion. The 13 bacteriologically positive biopsies belonged to the Group II cows from which 31 isolates contained 6 different genera of facultative and obligate anaerobic bacteria. Actinomyces pyogenes along with Bacteroides sp. and Fusobacterium necrophorum were found to predominate in a mixed flora. The bacteria were rapidly eliminated and disappeared completely from the uteri towards the end of the third week post-partum. The average number of days required for completion of uterine involution was 21.8 +/- 3.0 for all animals. The plasma levels of the PGF2 alpha metabolite were significantly elevated for the first 12-18, and 18 and 27 days in Group I and Group II, respectively. There was no significant relationship between the duration of PGF2 alpha release and the time required for completion of uterine involution (p > 0.05). Progesterone analysis showed resumption of ovarian activity and subsequent ovulation in 4 of the 9 cows 44-55 days post-partum. Thus, intrauterine infections are not commonly seen in cows with normal calving and comparison between the duration of PGF2 alpha release and the time required for completion of uterine involution showed insignificant correlation. However, the longer duration of PGF2 alpha release recorded in the 2 cows with intrauterine infections are related to the increased frequency of infections.

Prostaglandin F2 alpha metabolite and progesterone profiles in post-partum cows with retained foetal membranes

Post-partum prostaglandin release and resumption of cyclical ovarian activities were studied in 11 Swedish dairy cows with retained foetal membranes (RFM), leaving the RFM untreated. The main PGF2 alpha metabolite, 15-ketodihydro-PGF2 alpha, was measured in blood plasma collected twice daily during the first 50-60 days after delivery. Progesterone was monitored from all morning samples to evaluate the resumption of ovarian activity. The plasma levels of 15-ketodihydro-PGF2 alpha were arbitrarily considered to be significantly elevated between 6-24 days when they exceeded the mean basal value + 2 standard deviations. Comparison between this duration in days of the post-partum PGF2 alpha release and the time required for the completion of uterine involution, placental shedding and last day of post-partum clinical signs showed no significant relations. However, prior to a final decrease below a line of significance of 233-590 pmol/l, pronounced sustained and pulsatile release of PGF2 alpha occurred in relation to the increased frequency of the bacteriological findings. These additional periods of PGF2 alpha release were described as the "total" duration of post-partum release, and were found to be positively correlated with the time required for uterine involution from the stand point of rectal palpation (p < 0.05), while a tendency towards a positive relationship existed for the last day post-partum of clinical signs (p = 0.11). Progesterone analysis revealed resumption of ovarian activity and the first ovulation occurred between 19-29 days in 70% of the cows. The levels of the PGF2 alpha metabolite were again high at the time of luteolysis, thus terminating the luteal phase in the ovulating animals. Thus, it is seen that non-removal of the RFM or the resultant intrauterine infection do not prolong the duration of the immediate post-partum release of PGF2 alpha as compared to normal animals. However, a second release is associated with the increased frequency of uterine infections, indicating that PGF2 alpha may play a role for the early elimination of the infections.

Ultrasonography of the bovine postpartum uterus with retained fetal membranes

The aim of this study was to describe the potential application of ultrasound in combination with the rectal palpation method and to compare the results to determine the involution period in 11 Swedish dairy cows with retained fetal membranes (RFM). The animals were examined three times a week during the first 8-week postpartum (PP) period. Significant quantity of abnormal vaginal discharges with concomitant accumulation of snowy fluid and thickening of the endometrial and uterine walls were interpreted as evidence of endometritis. The discharges decreased most markedly during the third week PP concomitantly with a marked decrease in the cervical and uterine size. Resumption of cyclical ovarian activity occurred within a month in 7 animals. Five of these cows had 2 ovulations and two animals had 1 and 3 ovulations, respectively. A slight increase of the cervix and uterine size was observed in all ovulating animals in relation to the oestrous periods. Several different calculation methods of the ultrasonographic results were evaluated to describe the completion of uterine involution and compared with findings at rectal palpation. The best congruency with rectal palpation was found to use a 0.5 cm difference for comparison of the previous pregnant and non-pregnant uterine horns in singleton cows and an 80% reduction of the uterine size in all studied animals.