Gabriela Hirsbrunner

Treatment of infectious arthritis of the radiocarpal joint of cattle with gentamicin-impregnated collagen sponges

Gentamicin-impregnated collagen sponges were used successfully in the treatment of chronic septic arthritis of the radiocarpal joint in two cattle. Both animals were moderately to severely lame and refractory to systemic antibiotics, and one of them was refractory to joint lavage and local antibiotics. The clinical diagnosis was confirmed by radiography and arthrocentesis. Arthroscopy was performed under general anaesthesia and, after debridement and lavage of the joint, gentamicin-impregnated collagen sponges were placed intraarticularly. Synovial fluid was sampled at 10 and 20 days after surgery and radiographs were taken three months (case 1) and two months (case 2) after surgery. The infection was eliminated from both animals and they recovered without residual lameness.

Quantitative mRNA Analysis of Eight Bovine 5-HT Receptor Subtypes in Brain, Abomasum, and Intestine by Real-Time RT-PCR

Abstract Serotoninergic pathways are involved in economically important bovine gastrointestinal (GI) motility disorders such as displaced abomasum and cecal dilatation/dislocation. The existing research tools to investigate the role of serotoninergic pathways in such disorders in ruminants comprise functional pharmacological methods, e.g., in vitro contractility studies in tissue baths, and electromyographical recordings in vivo. However, no tools for quantification of bovine serotonin receptor [5‐hydroxytryptamine receptor (5‐HTR)] expression were available so far. This study aimed to develop real‐time RT‐PCR assays for quantitative mRNA analysis of bovine 5‐HTR subtypes. Because the bovine 5‐HTR coding sequences (CDSs) were completely unknown, multiple species (human, mouse, and rat) alignment of complete CDS was used for primer design in highly homologous regions. LightCycler real‐time RT‐PCR assays (partial CDS) for the following bovine 5‐HTR subtypes were developed and validated: 5‐HTR1A, 5‐HTR1B, 5‐HTR1D, 5‐HTR1F, 5‐HTR2A, 5‐HTR2B, 5‐HTR2C, and 5‐HTR4. Intra‐ and inter‐assay coefficients of variation (CV) for the eight established assays were small, ranging from 0.49% to 2.46%. As a first physiological application, 5‐HTR mRNA expression levels were measured in brain, abomasum, and intestine of 10 healthy, lactating dairy cows. The 5‐HTR expression was quantified by normalization to the housekeeping gene glyceraldehyde‐phosphate‐dehydrogenase (GAPDH). The 5‐HTR subtype expression levels ranged from 0.001% (5‐HTR2C in intestine) to 1% 5‐HTR/GAPDH (5‐HTR1B and 5‐HTR4 in intestine). There were high variations of 5‐HTR subtype mRNA expression within tissues across receptor subtypes and within receptor subtypes across tissues. In conclusion, accurate real‐time RT‐PCR assays for quantitative analysis of bovine 5‐HTR subtype gene expression were developed and validated.

Comparison of thelotomy and theloscopic triangulation for the treatment of distal teat obstructions in dairy cows - a retrospective study (1994-1998)

The medical records of 56 cows suffering from teat obstructions in the area of the rosette of Furstenberg were reviewed; 22 were treated by thelotomy and 34 by theloscopic triangulation and the long-term results were reviewed by telephone conversations with the owners up to four years after the surgery. The milk flow at the fourth milking session after surgery was significantly better in the cows treated by theloscopy and, as a result, fewer of these cows required the teat sphincter to be cut. The cows treated by theloscopy also stayed in hospital for a significantly shorter period and suffered fewer episodes of mastitis.

Immunization against gonadotropin-releasing hormone in dairy cattle: Antibody titers, ovarian function, hormonal levels, and reversibility

Suppression of cyclic activity in cattle is often desired in alpine farming and for feedlot cattle not intended for breeding. A cattle-specific anti-GnRH vaccination (Bopriva, Zoetis Australia Ltd., West Ryde, Australia) is approved for use in heifers and bulls in New Zealand, Australia, Mexico, Brazil, Argentina, Turkey, and Peru. Eleven healthy, cyclic Swiss Fleckvieh cows were included in the study and vaccinated twice with Bopriva 4wk apart. Injection site, rectal body temperature, and heart and respiratory rates were recorded before and 3d following each vaccination. Blood samples were taken weekly for progesterone and estrogen analysis and to determine GnRH antibody titer. Ovaries were examined weekly, using ultrasound to count the number of follicles and identify the presence of a corpus luteum. Thirty weeks after the first vaccination, the cows were subjected to a controlled internal drug-releasing device-based Select-Synch treatment. The GnRH antibody titers increased after the second vaccination and peaked 2wk later. Estrogen levels were not influenced by vaccination, and progesterone level decreased in 7 of 11 cows up to 3wk after the second vaccination and remained low for 10 to 15wk following the second vaccination. The number of class I follicles (diameter ≤5mm) was not influenced by vaccination, whereas the number of class II follicles (diameter 6-9mm) decreased between 7 and 16wk after the first vaccination. Class III follicles (diameter >9mm) were totally absent during this period in most cows. The median period until recurrence of class III follicles was 78d from the day of the second vaccination (95% confidence interval: 60-92d). After vaccination, all cows showed swelling and pain at the injection site, and these reactions subsided within 2wk. Body temperature and heart and respiratory rates increased after the first and second vaccinations and returned to normal values within 2d of each vaccination. The cows in our study were not observed to display estrus behavior until 30wk after the first vaccination. Therefore, a Select-Synch protocol was initiated at that time. Ten cows became pregnant after the first insemination (the remaining cow was reinseminated once until confirmed pregnancy). Bopriva induced a reliable and reversible suppression of reproductive cyclicity for more than 2mo. The best practical predictor for the length of the anestrus period was the absence of class III follicles.

Influence of prostaglandin E2 on parturition in cattle

A double-blinded, randomised, placebo-controlled field study of the influence of prostaglandin E2 (pge2) on cattle at parturition was carried out. The extent of cervical opening and the intensity of labour were scored before administration of the compound and 10 minutes later; routine birth assistance was then continued by the veterinarian. Successful birth occurred more quickly in the cows treated with pge2. The extent of cervical opening before the administration of the drug had a significant effect on the time to delivery, but the intensity of labour and a concomitant infusion of calcium did not have significant effects on this period. The less open the cervix before administration of the drug, the more the duration of parturition differed between the two groups, with the placebo group taking longer. A telephone follow-up inquiry found no significant differences between the cows postpartum; there were cases of mastitis and hypocalcaemia in both groups. The incidence of retained fetal membranes and the mortality of the calves were higher in the placebo group, but in neither case was the difference significant.

The myometrial contractility during late pregnancy in dairy cows, in vitro

This study aimed to investigate the in vitro contractility of the myometrium and its relationship to the blood concentrations of estradiol-17β (E2β), progesterone (P4), 15-keto-13,14-dihydro-PGF2α (PGFM) and ionised calcium (Ca2+) prior to tissue harvest in 12 healthy Holstein-Friesian cows in late pregnancy. Three circular (CM) and 3 longitudinal myometrial (LM) strips were dissected during a caesarean section and mounted in an organ bath containing modified Krebs solution (KS). The spontaneous contractility was recorded during five 30-min time periods (T1 to T5), after which the strips were exposed to increasing concentrations of oxytocin (OT; 10-10-10-7M), a natural PGF2α-analogue (PGF; 10-7-10-4M) and KS (Cont) for four 30-min time periods (T6 to T9). The variables area under the curve (AUC), mean (MA) and maximal amplitude (maxA) were calculated for each T. The blood P4, E2ß, Ca2+ and PGFM values averaged 4.0±1.7ng/mL, 482.3±63.7 pg/mL, 0.8±0.3 mmol/L and 125.3±63.7pg/mL. The LM strips had greater AUC, MA, and maxA than CM, and OT caused greater AUC and MA in both muscle layers than PGF or control treatment (OT>PGF>Cont). Estradiol-17β correlated with AUC and MA of LM at T1 to T5 (r=0.69; P≤0.05). In conclusion, LM and CM strips have different contractile performance but show enhanced activity when stimulated with OT and less activity after PGF stimulation if compared with Cont. Blood concentrations of E2β may be useful as an indicator of uterine contractile performance in late pregnant cattle.

A novel technique for surgical removal of protruded perivaginal fat in cattle

Perivaginal fat protrusion is a complication of soft tissue laceration in cases of dystocia in cattle. The vaginal wall is able to heal around the perivaginal fat prolapse, leaving a pedunculated mass of fat covered with granulation tissue (Hull 1995). When the cow lies down or strains, this mass protrudes through the vulva, and the surface often becomes necrotic due to recurrent exposure. The prolapsed tissue usually originates from the lateral vaginal wall. Pedunculated masses of perivaginal fat are often misdiagnosed as tumours (Hull 1995). Arbeiter and Mayer (1967) have described fat tissue protrusion through the vaginal wall in primiparous as well as in multiparous cows. The protrusion was always located in the region of the hymen (Arbeiter and Mayer 1967). Each case described in their study had a history of assisted calving one to two weeks before being referred for treatment. Particularly at first calving, livestock owners underestimate the time needed for dilatation of soft tissue, leading to premature forced extraction. Different techniques are described for the excision of the protruded fat tissue: Arbeiter and Mayer (1967) propose an episiotomy and the excision of the fat prolapse with a scalpel and the tamponade of the wound cavity with a resorbable sponge (Spongostan Johnson & Johnson Medical GmbH). Hull (1995) proposed making small cuts in the surface of the protruded fat to produce a gradual protrusion of fat from the inside and then the stepwise excision of the fat tissue avoiding the risk of deep dissection and massive bleeding. Wolfe and Carson (1998) finally described the removal of the fat tissue with an emasculator. The aim of the present case series is to describe a novel surgical technique to easily and safely remove prolapsed perivaginal fat tissue. Six adult Eringer cows (numbers 1–6; number 6 was referred …