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W Heuwieser

Publications and source records attributed to W Heuwieser.

At least 19 recordsLinked to original sources

Factors associated with high milk test day somatic cell counts in large dairy herds in Brandenburg. I: Housing conditions.

The aim of this study was to examine influences of housing conditions on the udder health in 80 German dairy herds with a herd size between 100 and 1100 cows. Data were collected using a standardized questionnaire for the farm manager and a farm visit using a standardized data capture form on hygiene and management. The somatic cell counts of all lactating cows on each farm were collected monthly by the local dairy herd improvement association and analysed to assess udder health status. Factor analysis was used to analyse the variables describing the environmental hygiene. The values derived for the extracted components were classified into good, moderate and poor. The association of the categories was then analysed for their influence on log somatic cell count of the current month (CMSCC) and the year before the farm visit (YASCC) by a one-way anova. In comparison to other housing systems, free stalls with cubicles had the lowest geometric mean somatic cell count. Three components were derived from the factor analysis. Of those, acceptance of the cubicles by the cows and barn hygiene were determined as components influencing the CMSCC and YASCC significantly, while the association of hygiene of the milking parlour with somatic cell counts was only significant for YASCC. The results of the study show that the cow comfort and housing hygiene have a substantial impact on milk quality and should therefore become the focus of further research on the farm management practices.

Analysis of Variance↗

Factors associated with high milk test day somatic cell counts in large dairy herds in Brandenburg. II. Milking practices.

The objective of this study was to examine the influences of different milking practices on cow udder health in 80 large dairy herds (range 100-1100 cows) in Brandenburg, Germany. Milking practices were evaluated during one complete milking using a standardized data capture form. The somatic cell count (SCC) of all lactating cows on each farm was determined monthly by the local milk recording association 'Landeskontrollverband Brandenburg'. Factor analysis was used to investigate the relationship between the different aspects of the milking practices. The components extracted by the factor analysis were examined for their influence on the SCC of the current month (CMSCC) and the year before the visit (YASCC) using univariate analysis of variance. Three components were extracted from the milking practices. 'Reasonable use of water' was significantly related to CMSCC (P = 0.019) and YASCC (P = 0.003). It included information on the use of a hose to clean udders before milking, cleaning of the floor between groups and use of water to clean teats. 'Attention of the milkers' was also significantly associated with CMSCC (P = 0.012) and YASCC (P = 0.014). It included information on the accuracy of mastitis detection by foremilk screening and the regular use of post-milking teat and cluster disinfection. The component 'preparation routines' (method of udder cleaning and forestripping) did not significantly influence CMSCC and YASCC. These results indicate that excessive use of water in the parlour during milking time is harmful to udder health and that the consistency of procedures in the milking parlour presents significant room for improvement in large dairy herds in Brandenburg.

Analysis of Variance↗

Strategies to improve the therapy of retained fetal membranes in dairy cows.

In this field trial, a protocol for the treatment of retained fetal membranes (RFM) without any intrauterine therapy was compared with 3 protocols based on the intrauterine use of antibiotic pills (AP), the manual removal (MR) of the fetal membranes, or the combination of both (PR). The study was conducted on 5 commercial dairy farms in Germany. Cows with RFM for at least 24 h after calving were assigned to 1 of 4 treatment groups. Cows of all groups with a rectal temperature >or= 39.5 degrees C received a systemic antibiotic treatment with ceftiofur (1 mg/kg per d) for 3 to 5 consecutive days. In case of continued fever after 5 treatments, cows received a different antibiotic as an escape therapy. In the reference group (REF; n = 131), cows did not receive any additional treatment. All cows in group AP (n = 119) received intrauterine treatment with antibiotic pills consisting of 1,000 mg of ampicillin and 1,000 mg of cloxacillin for 3 consecutive days. In group MR (n = 121), an attempt was made to remove the fetal membranes manually, but uterine pills were not administered. In group PR (n = 130), an attempt was made to remove the fetal membranes manually and all cows received a local antibiotic treatment as in group AP. All cows received 2 doses of 25 mg of PGF(2alpha): one dose between 18 and 24 d and another between 32 and 38 d postpartum. Statistical analyses were performed using binary logistic regression models and survival analyses with group REF as reference. Of all animals, 79.8% had a body temperature of >or= 39.5 degrees C at least once within 10 d postpartum and were treated with ceftiofur. Occurrence of fever within 10 d postpartum was significantly lower in groups AP and PR compared with reference group REF, but was not different between groups MR and REF. Risk of receiving an escape therapy in case of fever after 5 treatments with ceftiofur did not differ among groups. Reproductive performance measures did not differ significantly between group REF and any of the comparison groups. Compared with a treatment protocol based only on systemic treatment with antibiotics for cows with a fever, neither intrauterine antibiotics nor manual removal of fetal membranes alone or in combination reduced proportions of cows needing an escape therapy nor did those treatments improve reproductive measures in the current lactation. Systemic treatment alone based on elevated rectal temperature was effective and reduced use of antibiotics compared with therapies that included intrauterine antibiotics.

Ampicillin↗

Comparison of two strategies for systemic antibiotic treatment of dairy cows with retained fetal membranes: preventive vs. selective treatment.

The objective of this study was to evaluate the efficacy of a blanket systemic preventive treatment (PT) of cows having retained fetal membranes (RFM) with 1 mg/kg of ceftiofur administered the first day after calving regardless of their body temperature. This strategy was compared with a selective treatment (ST) strategy in which only cows having RFM and a rectal temperature > or = 39.5 degrees C within 10 d postpartum received ceftiofur. Cows that retained their fetal membranes for at least 24 h after calving were allocated to 2 groups. Rectal temperature was measured daily for 10 d postpartum. Sixty PT cows having RFM received a daily ceftiofur (1 mg/kg of body weight) treatment, administered subcutaneously during the first 3 d after diagnosis of RFM. If rectal temperature was > or = 39.5 degrees C after 3 daily treatments, cows received ceftiofur for 2 more days. Therapy in 53 ST cows was based on selective administration of ceftiofur to cows having fever during the first 10 d postpartum. Treatment was conducted for 3 to 5 consecutive days as described for PT cows, beginning on the first day of fever. In both groups, manual removal of the placenta was not attempted and antibiotic drugs were not administered into the uterus. For every cow having RFM enrolled in PT or ST, 1 cow without RFM that had calved on the same day was enrolled in a healthy control group (n = 113). All cows received two 25-mg doses of PGF(2alpha): 1 dose between 18 and 24 d and 1 dose between 32 and 38 d postpartum. The PT did not reduce the proportion of cows experiencing fever during 10 d postpartum compared with ST cows (71.7 vs. 69.8%). Results were compared using logistic regression models and survival analyses. The artificial insemination submission rate between 42 and 62 d postpartum was greater in PT (41.2 vs. 20.8 vs. 24.5%), but total conception rate was less in ST and control cows, respectively (25.0 vs. 38.9 vs. 36.2%). In this trial, a preventive systemic antibiotic treatment of all cows having RFM was not superior to a selective antibiotic treatment of cows only in case of fever.

Animals↗

Prevalence of mastitis pathogens and their resistance against antimicrobial agents in dairy cows in Brandenburg, Germany.

The primary objective of this study was to determine management practices concerning mastitis in Brandenburg, Germany, the prevalence of mastitis pathogens in dairy cows, and their resistance to selected antimicrobial agents. A further objective was to study the potential effect of parity and stage of lactation on the resistance of Staphylococcus aureus isolates against ampicillin. Milk samples for microbiological culture were collected from 4 groups of clinically healthy cows (first lactation, >1 lactation, >50 d in milk, and >250 d in milk; 8 cows/group) in 80 dairy herds. Resistance of gram-positive pathogens against 6 antimicrobial agents was tested using the broth microdilution method. Mastitis pathogens were isolated from 26.4% of the milk samples. Coagulase-negative staphylococci (CNS, 9.1% of quarters) and Corynebacterium bovis (7.3%) were the pathogens most frequently isolated. Among the major pathogens, Staph. aureus (5.7%) and Streptococcus uberis (1.0%) had the highest prevalence. Streptococcus agalactiae was isolated in samples from 29% of the herds. Although the prevalence of most pathogens was higher in older cows, the prevalence of CNS was higher in primiparous cows. Results of the mastitis control questionnaire showed that cows with clinical mastitis were transferred to a sick cow pen in 70% of the herds. Cephalosporins were the drug of first choice for treatment of clinical mastitis cases followed by fixed combinations of antimicrobial agents, beta-lactamase-resistant penicillins, and penicillin. Most farmers treated cows 3 to 4 times per case. Cloxacillin, alone or in combination, and penicillin were most often used for dry-cow therapy. Antimicrobial resistance of the pathogens was within the range of other reports. Resistance of Staph. aureus to ampicillin increased significantly during the first lactation. Further research is required to determine the factors that lead to the selection of Staph. aureus strains that are resistant to ampicillin during the first lactation.

Ampicillin Resistance↗

Ceftiofur derivatives in serum, uterine tissues, cotyledons, and lochia after fetal membrane retention.

The objective of the study was to determine concentrations of ceftiofur derivatives after subcutaneous application of ceftiofur hydrochloride in cows with retained fetal membranes. Concentrations of ceftiofur derivatives detected as desfuroylceftiofuracetamide were determined in blood serum, endometrium, caruncles, cotyledons, and lochia during 72 h. After induction of parturition, 2 primiparous and 4 multiparous cows having retained fetal membranes for at least 12 h were studied. All cows received 3 consecutive injections (C1 to C3; 24 h apart) of 1-mg ceftiofur equivalents per kilogram of body weight as ceftiofur hydrochloride sterile suspension. Samples of blood, endometrium, caruncles, cotyledons, and lochia were collected immediately before each injection (0 h) and again at 4, 12, and 24 h after C1, C2, and C3. Blood samples were collected from coccygeal vessels. Caruncles were removed from the uterine lumen by manual extirpation and separated from cotyledons. Endometrial tissue (0.5 g) was collected by using Kenny's biopsy apparatus. For all samples, concentrations of potentially active ceftiofur derivatives were quantified using an HPLC assay. Within 2 h (serum), 4 h (endometrium), and 12 h (caruncles, cotyledons, lochia) after C1 and during the entire study period, mean concentration of ceftiofur derivatives exceeded the reported minimum drug concentrations required to inhibit the growth of 90% of isolates for relevant bacteria such as Escherichia coli, Fusobacterium necrophorum, and Arcanobacterium pyogenes. Only in single samples did concentrations decrease temporarily below the reported minimum drug concentrations required to inhibit the growth of 90% of isolates.

Animals↗

[Seasonal influence on the microbiological colonization on surfaces of milk liners and flushing adapters in a newly installed milking parlor].

A field trial was conducted to evaluate long term and seasonal effects on the development of mictobiological colonization in a newly installed milking parlor. The milking equipment was a 2 x 34 side-by-side milking parlor in a commercial dairy herd in Germany. The 1st batch of samples was taken before beginning of milking and in weekly intervals for a period of two months in winter 2002. The 2nd batch of samples was collected in summer 2003. After sampling the diagnostic material was kept in Amies medium at 4 degrees C until analysis. Samples were analyzed from the mouthpiece, the shank of the liner and the flushing adapter. The samples were collected immediately after disinfection of the milking equipment. They were analyzed qualitatively and quantitatively according to the official German guidelines (Amtliche Sammlung von Untersuchungsverfahren, paragraph 35, LMBG). Mesophil aerobe total plate count, S. aureus, E. coli, Coliforms, Streptococci, Yeast and Lactobacilli were considered. Results indicate a relationship of microbiological colonization of the surface of the milking technique with season and location of sampling. The microbiological colonization was higher in summer than in winter. There were more mesophil aerobe pathogens on the flushing adapters than on mouthpiece and shank of the liner.

Animals↗

Timing of ovulation and fertility of heifers after synchronization of oestrus with GnRH and prostaglandin F(2alpha).

Synchronization of oestrus and/or ovulation can reduce workload in heifer reproductive management. The objective of this study was to compare two protocols to synchronize oestrus and/or ovulation using GnRH and prostaglandin F(2alpha) (PGF(2alpha)) in dairy heifers concerning their effect on follicular dynamics and reproductive performance. Four trials were carried out. In trial 1, 282 heifers were treated with GnRH and PGF(2alpha) 7 days apart (GP protocol). One group was inseminated on detection of oestrus (IDO 1), and the other group received two timed artificial inseminations (AI) 48 and 72 h after PGF(2alpha) administration (TAI 1). In trial 2, 98 heifers were synchronized with the same GP protocol. Heifers in IDO 2 were treated as in IDO 1, heifers in TAI 2 received two TAI 48 and 78 h after PGF(2alpha) administration. In trial 3, heifers in IDO 3 (n = 71) were again treated as in IDO 1. Heifers in TAI 3 (n = 166) received a second dose of GnRH 48 h after PGF(2alpha) (GPG protocol) and TAI together with this treatment and 24 h later. Trial 4 compared the timing of ovulation after the GP and the GPG protocol, using a subgroup of the heifers from trials 1 to 3. The ovaries of the heifers were scanned via ultrasound at 48, 56, 72, 80, 96 and 104 h after PGF(2alpha) administration. Timing of ovulation and size of the ovulatory follicles were compared between the two groups. In trials 1 to 3, conception rates to first service were between 49 and 66%. They did not differ significantly between IDO and TAI groups within or between trials. Pregnancy rates per synchronization were numerically higher in the TAI groups, but the difference was not significant. Conception rates to breeding on spontaneous oestrus in heifers returning to oestrus were higher than that after synchronized oestrus. In trial 4, more heifers ovulated before the end of the observation period in GPG than in GP (96.5% vs 74.7%; p < 0.001). Overall, ovulatory follicles were smaller in GPG (13.1 +/- 1.9 mm vs 14.3 +/- 1.9 mm; p < 0.001).

Animals↗

[Development of cell content and shedding of Prototheca spp. in milk from infected udder quarters of cows].

It was the objective of this study to analyse shedding patterns and somatic cell counts in cows and quarters infected with Prototheca spp. and to evaluate two approaches to identify infected animals by somatic cell count (SCC) or by bacteriological analysis of pooled milk samples. Five lactating dairy cows, chronically infected with Prototheca spp. in at least one quarter were studied over 11 weeks to 13 months. Quarter milk samples and a pooled milk sample from 4 quarters were collected aseptically from all quarters of the cows on a weekly basis. Culture results of quarter milk and pooled samples were compared using cross tabulation. SCC of quarter milk samples and of pooled samples were related to the probability of detection in the infected quarters and cows, respectively. Shedding of Prototheca spp. was continuous in 2 of 8 quarters. In the other quarters negative samples were obtained sporadically or over a longer period (1 quarter). Overall, Prototheca spp. were isolated from 83.6% of quarter milk samples and 77.0% of pooled milk samples of infected quarters and cows. Somatic cell counts were higher in those samples from infected quarters that contained the algae than in negative samples (p < 0.0001). The same applied for composite samples from infected cows. Positive samples had higher SCC than negative samples. However, Prototheca spp. were also isolated from quarter milk and pooled samples with physiological SCC (i.e. < 10(5)/ml). Infected quarters that were dried off did not develop acute mastitis. However, drying off had no effect on the infection, i.e. samples collected at calving or 8 weeks after dry off still contained Prototheca spp. Results indicate that pre-selection of cows to be sampled for Prototheca spp. by SCC and the use of composite samples are probably inadequate in attempts to eradicate the disease. However, due to intermittent shedding of the algae in some cows, single herd sampling using quarter milk samples probably also fails to detect all infected cases. Therefore, continuous monitoring of problem cows with clinical mastitis or increased SCC in herds during eradication programs is recommended.

Animals↗

[Evidence based veterinary medicine].

The characteristics and advantages of evidence based (human-) medicine (EBM) are introduced. By summarising information and analysing the results of different clinical trials relating to a specific topic by expert commissions concise and advanced conclusions can be formulated. That kind of evidence (certainty that results are true) increases the explanatory power of a single trial by far. Precondition for the development of an evidence based veterinary medicine (EBVM) is an improvement of the quality, design and implementation of clinical trials. Continuous publication of these conclusions (EBVM) can support the practitioner or clinician in the decision making process for an optimal treatment. Furthermore the implementation of state of the art intervention strategy is assured.

Animals↗

[Influence of time of initiation of a prostaglandin F2alpha protocol in dairy cows with puerperal endometritis].

A field trial was conducted to elucidate the effect of the time of initiation of a repeated PGF2alpha-application in a 14 day interval for treatment of endometritis in dairy cows. On a commercial dairy farm in Brandenburg, Germany, a total of 494 dairy cows were examined by rectal palpation and adspection for signs of endometritis (vaginal discharge, enlarged uterus) between day 20 to 26 post partum (dpp). We performed two further examinations by rectal palpation and external adspection to monitor the puerperal phase (34.-40. dpp, 55.-61. dpp). All cows with symptoms of an endometritis were treated with PGF2alpha (0.15 mg R-Cloprostenol, Preloban, Intervet Deutschland GmbH Unterschleissheim) twice in a 14-day interval. In the group "Early" (n = 146) the first injection of Cloprostenol was administered at time of the 1st examination. In the group "Late" (n = 129) an identical treatment was administered in cows with endometritis, however it was started 14 days later (34.-40. dpp). The incidence of endometritis was 57.7% in the group "Early" and 53.5% in the group "Late" at the first time of examination. The 1st service conception rates for treated cows were 34% in the group "Early" vs. 37% in the group "Late". In the group "Early" differences were found in days open between treated cows with endometritis and untreated controls without symptoms of endometritis (99.1 d vs. 110.8 d, p > 0.05). In the group "Late", days open for treated (106.8 d) and untreated cows (108.0 d) were similar. The severity of endometritis influenced the percentage of cows pregnant at 200 dpp. Regarding cows with a severe endometritis (E2 and E3) the percentage of pregnant cows 200 dpp was higher in the group treated early (E2: 78.4%; E3: 80.0%) than in the group with the late initiation of the treatment (E2: 68.6%; E3: 54.5%, p < 0.05). Cows with a moderate endometritis (E1) had a similar percentage of pregnant cows (200 dpp) as the untreated cows without endometritis. It is concluded that application of PGF2alpha in the 4th and 6th week post partum in a 14 day interval in cases of severe endometritis is more effective than the application of the same treatment two weeks later.

Animals↗

[Comparision of ovulation synchronization (OVSYNCH) with the selective induction of oestrus using PGF2alpha after rectal palpation in a dairy herd].

The efficacy of a protocol for the synchronization of ovulation followed by timed Al (OVSYNCH) was compared with a reproductive management protocol based on induction of oestrus after rectal palpation using PGF2alpha on a commercial dairy farm in Brandenburg, Germany. Cows in the OVSYNCH group (n = 309) were treated between 62 and 68 days in milk (DIM) with 0.02 mg of buserelin (GnRH analogue) intramuscularly (i.m.). Seven days later 0.75 mg of tiaprost (PGF2alpha-analogue) were administered i.m. to regress the corpus luteum (C.I.). All cows received a second treatment with GnRH another 48 hrs later and were inseminated 16 to 20 hrs after the second GnRH-treatment (72 to 78 DIM). Cows in the PGF group (n = 302) were examined by rectal palpation between 69 and 75 DIM. Cows with a C.I. received 0.75 mg of tiaprost to induce oestrus. Cows were inseminated on observed oestrus. Cows not inseminated within 14 days after treatment were re-examined between 83 and 89 DIM. For both groups, the voluntary waiting period was set at 72 DIM. Service rate was higher (86.4 vs. 63.2 %, P < 0.05), days to first service (77 +/- 11 vs. 86 +/- 19 days, P < 0.001) and days open (102 +/- 34 vs. 109 +/- 35 days, P < 0.05) were shorter in the OVSYNCH group. First service conception rate (40.3 vs. 42.4 %), conception rate to all services (37.9 vs. 40.0 %) and the proportion of pregnant cows at 200 DIM were similar in the OVSYNCH evaluation for the total costs per pregnancy in 71 different cost scenarios showed only slight differences between the groups. Mean costs per pregnancy were euro 235.43 and euro 235.08 for the OVSYNCH and the PGF group, respectively. Quality of oestrus as assessed by the Al technician did not reveal a relationship to conception rate after OVSYNCH and timed Al. However, swelling, hyperaemia and a moist vestibulum were positively associated with conception rate.

Animals↗

Comparison of timed AI after synchronized ovulation to AI at estrus: reproductive and economic considerations.

A timed artificial insemination (TAI) protocol using OvSynch was compared to artificial insemination (AI) at detected estrus in 2 large dairy herds differing in reproductive management. Cows were synchronized for TAI starting at 62 and 42 d in milk in herds 1 and 2, respectively. The OvSynch regimen included: GnRH (buserelin) at 0.02 mg (i.m.) on d 0; PGF2alpha (tiaprost) at 0.75 mg (i.m.) on d 7; buserelin at 0.02 mg (i.m.) on d 9; and TAI 16 to 20 h later. After TAI, cows seen in estrus received AI, whereas cows diagnosed not pregnant were resynchronized for TAI. Control cows received AI based on detected estrus after voluntary waiting periods of 72 d in herd 1 and 50 d in herd 2. An economic analysis included costs associated with days open, culling, AI, synchrony products, treatment, and examinations. A sensitivity analysis of those variables determined effects on total costs per pregnancy. Use of OvSynch reduced intervals to first AI and days open in both herds and reduced culling for infertility in herd 2. Conception rates for first AI at detected estrus were significantly higher compared to TAI in both herds and for overall AI at estrus in herd 2. For groups assigned to AI at estrus, mean 21-d submission rates over 200 d for AI were higher in herd 1 than in herd 2 (55.6 vs. 28.6%). Days open and culling were the major cost factors. Although OvSynch improved reproduction in both herds, AI based on detected estrus was economically superior in herd 1, whereas OvSynch was superior in herd 2. This was consistent across ranges of cost factors evaluated. Evaluation of synchrony protocols should include reproductive performance along with appropriate costs associated with treatments. Such costs may offset benefits to reproduction in herds with good estrous detection rates.

Animals↗

[Relationship between morphological characteristics of the teat duct and prevalence of intramammary infections with Streptococcus agalactiae in dairy cows].

The objective of the study was to determine the relationship between morphological findings of the surface of teat duct particularly the level of ceratosis and the prevalence of intramammary infections (IMI). The study was conducted on a commercial dairy herd housing about 3000 lactating dairy cows. We examined 891 quarters in the middle of lactation. Duplicate samples of quarter foremilk were collected monthly. The bacteriological status of quarters was determined according to the recommendations of IDF. At the same time teats were evaluated by clinical examinations. The appearance of teat skin lesions and the status of the teat duct especially the existence of hyperceratosis (HC) was documented. Four classes of teat duct hyperceratosis were defined: without, slight, medium and severe HC. The rate of IMI in different classes of hyperceratosis of teat duct was compared by Chi-square analysis. Prevalences of intramammary infections were determined three times (P1, P2 and P3) during the study period. Prevalence of infection was high for S. aureus (P1: 5.6% vs. P2: 4.5% vs. P3: 4.3%), Sc. agalactiae (P1: 2.7% vs. P2: 2.6% vs. P3: 2.8%) and CNS (P1: 10.7% vs. P2: 8.8% vs. P3: 9.6%). Furthermore we detected IMI caused by other streptococci, yeast, E. coli and mixed infections. A positive correlation between status of HC and prevalence of IMI for Sc. agalactiae was found. At the second and third sampling time the rate of intramammary infection with Sc. agalactiae in quarters with medium HC (P2: 9.21% and P3: 13.73%) differed significantly (p < 0.05) compared to groups without (P2: 1.56% and P3: 1.91%) and slight hyperceratosis (P2: 2.33% and P3: 2.56%). The results of our study indicate a correlation between morphology of teat duct surface, especially regarding to Sc. agalactiae. On one hand HC can cause high intramammary infection rate with Sc. agalactiae. On the other hand it is possible that HC is the consequence of a quarter infection with Sc. agalactiae. Further research is required.

Animals↗

Timing of ovulation and conception rate in primiparous and multiparous cows after synchronization of ovulation with GnRH and PGF2alpha.

Conception rates after Ovsynch have been higher in primiparous than in multiparous cows. The objective of this study was to investigate whether this difference might be due to differences in ovulation rate or follicular size. The experiment was conducted with 136 Holstein Frisian cows from a commercial herd in Brandenburg, Germany. All cows were synchronized using Buserelin (GnRH analogue) at day -10, Tiaprost (PGF2alpha analogue) at day -3 and again GnRH at day -1. Timed artificial insemination (TAI) was carried out 16-20 h after the second dose of GnRH on day 0. Milk samples for analysis of milk progesterone were obtained on days -17, -10, -3 and at TAI. Progesterone concentrations were used to determine the stage of oestrus cycle at the start of the synchronization protocol and to investigate the presence of functional luteal tissue before treatment with PGF2alpha and TAI. All animals were examined by ultrasound at the second treatment with GnRH, at AI, 8 and 24 h after AI. Overall synchronization rate (proportion of cows with an ovulation within 40 h after GnRH) was 86.8% in primiparous and 88.2% in multiparous cows, respectively. Ovulation occurred earlier in primparous than in multiparous cows (p < 0.05) and ovulatory follicles were smaller. Conception rates were numerically higher in primiparous cows but the difference was not significant. Cows that displayed signs of oestrus on day -1 and received an additional AI on this day were more likely to conceive than cows that only received TAI 16 to 20 h after GnRH2. It is concluded that ovulation occurs earlier in primiparous than in multiparous cows after Ovsynch. However, a significant relationship between these differences and the probability of conception could not be established.

Animals↗

[The clinical effectiveness of a post milking teat disinfection method with a foaming iodophor teat dip].

The effect of postmilking teat dipping with a foaming iodophor agent on incidence of intramammary infections (IMI), incidence of clinical mastitis, somatic cell count and the characteristics of udder tissue and teat was investigated in a positively controlled field study. Two groups of animals were compared. Teats were dipped with a foaming iodophor in the treatment group (TG, 122 animals) while teats in the control group (CG, 121 animals) were dipped with a conventional iodophor teat dip with the same iodine content. A bacteriological examination of quarter milk samples divided the study period in two parts. The incidence of new IMI did not differ between the groups (1st part of trial: TG vs. CG: 6.84% vs. 9.16%, 2nd part of trial: 7.78% vs. 7.82%). There were no differences between the treatment groups regarding incidence of clinical mastitis. We detected 0.64 clinical cases per 100 days in the treatment group vs. 0.50 in the control group. The development of SCC was comparable in both groups. Teat skin and teat duct conditions showed variation during the study period. Clinical efficacy of postmilking teat disinfection with a foaming iodophor was comparable to the treatment with a conventional iodophor product.

Administration, Topical↗

[Do lactoferrin, lysozyme and the lactoperoxidase-thiocyanate-hydrogen peroxide-system cause negative microbiological results in mastitis secretions?].

Lactoferrin, lysozyme and the lactoperoxidase-thiocyanate-peroxide-system are naturally occurring antimicrobial components of milk. The objective of this study was to examine, whether these components were responsible for negative results, when mastitis milk is cultured microbiologically. Quarter milk samples from 75 cows with clinical mastitis on a dairy farm in Brandenburg were submitted for microbiological culture and analysed for the content and the activities of the three components. Animals from all stages of lactation with clinical mastitis were included in the study. Animals were examined clinically and milk samples were collected prior to first treatment. Secretions from quarters with clinical mastitis were compared to those of neighbouring quarters without clinical mastitis. Secretions with positive cultural results were compared to those with negative results. The concentrations or activities of the three factors were significantly higher in the diseased quarters than in the quarters without clinical signs of mastitis. The concentration of lysozyme increased with severity of the clinical signs (local swelling and changes in secretion). The concentration of lactoferrin was significantly higher in quarters with slight alterations of glandular tissue than in quarters with medium or severe alterations (P < 0.05). LPS-activities did not correlate with the severity of clinical signs. No differences in the concentration of lactoferrin or LPS-activities were seen between mastitis with positive and negative culture results. The concentration of lysozyme was even higher in culturally positive samples than in negative samples (P < 0.05). Results from this study indicate that the three factors examined did not impair the results of microbiological culture of milk samples from quarters with clinical mastitis.

Animals↗

[Effects of the intensity of a post partum examination on the fertility performance of high yielding dairy cows].

Two methods for a scheduled post partum examination were compared on a commercial dairy farm. In Group 1, all cows (n = 601) were examined by rectal palpation between day 20 and 26 post partum for signs of endometritis (vaginal discharge, enlarged uterus). In Group 2, all cows (n = 652) were examined by external inspection for vaginal discharge as a sign for endometritis. In both groups all cows with endometritis were treated twice with prostaglandin F2 alpha (25 mg of dinoprost) in a 14-day interval. The proportion of cows with signs of endometritis was 33.3% and 17.2% in Group 1 and Group 2, respectively (p < 0.05). In Group 1, the conception rate (39.0% vs 49.3%) and the proportion of cows pregnant (60.5% vs 72.6%) were lower for cows with endometritis than for cows without endometritis. In Group 2, no significant differences were found in reproductive performance for cows with and without signs of endometritis. No significant differences in reproductive performance were found for cows with endometritis between the two groups. Also, for cows without endometritis no significant differences in reproductive performance were found between the groups. It is concluded that the post partum examination by rectal palpation was more sensitive in finding cows with endometritis. However, with regard to the reproductive performance the more sensitive method was not more effective than the method based on systematic external inspection.

Animals↗