Metritis vaccination in Holstein dairy heifers using a herd-specific multivalent vaccine - Effects on uterine health and fertility in first lactation.

In cattle, acute puerperal metritis (APM) compromises animal welfare and has an economic impact to the farmer because of the detrimental effects on reproductive performance, milk production, and survivability. The aim of this randomized clinical study was to investigate the effects of a prepartum immunization using a herd-specific multivalent vaccine on incidence of APM, prevalence of clinical endometritis (CE), and selected measures of reproductive performance in primiparous Holstein cows. Pregnant nulliparous cows (230±4days of gestation) assigned to the vaccinated group (VG; n=142) received subcutaneously 5.0mL of a multivalent herd-specific vaccine containing inactivated whole bacterial cells of Trueperella pyogenes, Escherichia coli, Streptococcus uberis, Bacteroides species, and Peptostreptococcus species obtained from uterine swabs of primiparous cows suffering from APM at the time of enrolment and three weeks later. Heifers allocated to the control group (Co; n=144) remained unvaccinated. Rectal temperature in the first 10days in milk (DIM) did not differ between treatments, and no interaction between treatment and day was observed (interaction treatment*day: p=0.623). Incidence of APM (VG, 46.0%, Co, 48.9%, p=0.588), number of antibiotic doses per cow to treat APM (VG, 0.63±0.81, Co, 0.64±0.75, p=0.496), prevalence of CE at 35 DIM (VG, 24.6%, Co, 19.3%, p=0.350), first service pregnancy per artificial insemination (VG, 40.3%, Co, 45.5%, p=0.541), number of inseminations until 150 DIM (VG, 2.0±1.4, Co, 1.9±1.3, p=0.749), interval from calving to first service (median days, VG, 52, Co, 52, p=0.915), and interval from calving to pregnancy (median days, VG, 90, Co, 83, p=0.419) did not differ between VG and Co. Treatment did not affect activity of aspartate aminotransferase (AST) and creatine kinase (CK) or concentrations of beta-hydroxybutyrate (BHB) and haptoglobin in serum samples collected at 5 DIM. Furthermore, treatment did not influence yields of milk, fat or protein in the first 100 DIM. Moreover, no signs that vaccination provided an attenuation of severity of the APM cases were detected as the course of rectal body temperature and values of AST, CK, BHB, and haptoglobin were not influenced by treatment within the group of cows with diagnosed APM. Use of this herd-specific multivalent vaccine designed to reduce metritis was not efficacious at reducing the risk of uterine disease or influencing production and reproduction in dairy cows.

Lack of effects of an equine chorionic gonadotropin (eCG) administration between days 9 and 15 postpartum on reproductive performance in a Holstein dairy herd.

Recently, it has been demonstrated that administration of equine chorionic gonadotropin (eCG) in the postpartum period in dairy cows can enhance follicle growth, reduce the interval from calving to first ovulation and increase plasma estradiol concentrations, and, thus, could enhance reproductive performance in a dairy herd when administered on day 6 postpartum. The aim of this study was to investigate the effects of a single dose of eCG between days 9 and 15 postpartum on parameters of reproductive performance in dairy cows. German Holstein cows (n = 1937; primiparous cows: n = 748; pluriparous cows: n = 1189) in a commercial dairy farm were randomly assigned to three experimental groups. Animals within the group eCG received a single dose of 600 IU eCG intramuscularly (i.m.) between days 9 and 15 postpartum followed by an i.m. administration of 500 µg cloprostenol after 14 days. Those of treatment group PG received cloprostenol only between days 23 and 29 postpartum. Cows of the control group remained untreated. Starting on day 49 postpartum, cows were subjected to a Presynch-Ovsynch protocol and inseminated artificially. The impact of application time (days postpartum) of eCG on the intervals calving to first service and calving to conception was statistically not significant. Outcomes of reproductive performance (i.e. first service conception rate, proportion of pregnant cows until 100 and 150 days in milk [DIM], number of inseminations until 150 DIM, calving to first service interval and calving to conception interval) did not differ significantly between treatment group eCG and group PG compared to control group. Regarding postpartum eCG administration, significant interactions between treatment and parity, season, milk yield, and early puerperal disorders, respectively, could not be shown. In conclusion, an eCG treatment of dairy cows between days 9 and 15 postpartum to increase reproductive performance cannot be recommended under the given circumstances.

[Sporadic cutaneous lymphosarcoma of T-cell origin with involvement of lymph nodes and internal organs in a Holstein cow]. / Sporadische kutane T-Zell-Leukose mit Beteiligung von Lymphknoten und inneren Organen bei einer Holstein-Kuh.

Sporadic lymphosarcomas in adult cattle are rare entities with an unknown etiology. This case report describes the course of the disease in a 3.5-year-old cow of the breed German Holstein, which was presented to the veterinarian due to multifocal nodular skin lesions. Several superficial lymph nodes (Lymphonodi mandibulares, parotidei and mammariae) were enlarged, had a tight-elastic consistency and were freely movable. The histopathological and immunohistochemical examination of skin biopsies showed the presence of multifocal cutaneous T-cell lymphosarcomas consistent with a skin leukosis. Bovine leukemia virus infection was excluded by serological investigation of a milk sample and virological examination of a tissue sample, respectively. Seven weeks after the first clinical examination, the cow deteriorated rapidly and was euthanized. A post mortem examination revealed the presence of neoplastic cells within lymph nodes (all superficial lymph nodes of the carcass and Lymphonodi pulmonales), kidney and lungs as well as a liver rupture. Additionally, an overview of the case reports of sporadic bovine cutaneous lymphosarcomas published during the previous 15 years will be provided. The legal background for a further utilization of affected animals for milk and meat production will be discussed. This case report illustrates that sporadic bovine leukosis represents an important differential diagnosis for viral-, bacterial- and parasitic-induced skin lesions and enlargement of lymph nodes in adult cattle.

[Use of gonadorelin[6-D-Phe] at day 0 or 12 after insemination to increase the conception rate in a large dairy herd in Saxony/Germany]. / Einsatz von Gonadorelin[6-D-Phe] am Tag 0 oder 12 post inseminationem zur Steigerung der Konzeptionsrate in einer sächsischen Milchviehgroßanlage.

OBJECTIVE: To increase conception rates in lactating dairy cows by the application of a gonadotropin-releasing-hormone (GnRH)-agonist after insemination. MATERIAL AND METHODS: A total of 3125 inseminations of 1634 cows were included in this study. The animals were randomized into three groups at the time of insemination (day 0) using the final numeral of the ear-tag number: The cows of the GnRH0 group were treated using 100 µg gonadorelin[6-D-Phe] intramuscularly immediately after insemination (day 0), while those of the GnRH12 group were treated similarly at day 12. The cows of the control group received no hormonal treatment after insemination. An examination for pregnancy was performed at day 28 using transrectal ultrasonography. Analysis of the data sets was conducted for the number of inseminations (NI) 1-4 and for the last observed insemination of the respective cow during the experimental period, respectively. In a second step, statistical analysis was performed for the first service of cows with a lactation number of 1 versus > 1, with emphasis on the daily milk yield. In addition, a metritis diagnosed after the previous parturition was investigated as a possible factor influencing NI 1. RESULTS: Pregnancy risk at day 28 was decreased for NI 2 (n = 792) in the GnRH0 group compared to the control group (odds ratio [OR] = 0.69; 95% confidence interval [CI95] = 0.5-1.0; p = 0.04). A similar observation was found for NI 3 (n = 495) for the GnRH12 group (OR = 0.54; CI95 = 0.3-0.9; p = 0.01). In contrast, the pregnancy risk was increased for cows with a lactation number ≥ 2 and with a daily milk yield ≥ 42.5 kg (7-day-mean at day 0) at the first service (n = 364) by treatment with gonadorelin immediately after insemination (OR = 2.0; CI95 = 1.2-3.4; p = 0.01). No significant differences in the pregnancy risk were observed for the remaining analysed classes. CONCLUSION: An increased conception rate was only achieved for the first service of high-yield dairy cows (lactation number ≥ 2) by gonadorelin treatment at day 0. Presumably, the higher incidence of delayed ovulations in this group was treated successfully by gona- dorelin administration.