Johannes Kauffold

Prevalence of PCV2 in Austrian and German boars and semen used for artificial insemination

Since epidemiologically-based science on PCV2 in porcine semen is patchy, we investigated 806 Austrian (A) and German (G) AI boars from five studs, and boars from Austrian farms used for on-farm semen collection, for the presence for IgG/IgM in blood by ELISA (n=754) as well as for PCV2 DNA in semen (n=472) and if positive, also in blood of a few boars by nested PCR and sequencing. A total of 420 boars were tested for both PCV2 in semen and antibodies in blood. Boars were aged between 8 and 82 months at sampling. None of the boars tested positive for IgM but 60.1% did for IgG. PCV2 DNA was detected in 86 (18.2%) semen samples. Minor differences were found between boar populations with respect to the number of antibody positive boars and no differences for DNA in semen. Phylogenetic analysis of 28 sequences revealed a genetic diversity of PCV2 in semen within and between boar populations, with sequences belonging to both PCV2 genotypes 1 and 2. Mean nucleotide sequence identity was 95.7%, with maximum pairwise difference of 8.8%. Boars < or =16 months were tested more frequently positive for IgG (P<0.001) and for PCV2 DNA in semen (P<0.05) than older boars. Of 80 boars tested positive in semen, 34 (42.5%) were antibody negative. A total of 58 semen positive boars with (n=33) and without (n=25) IgG were all tested negative for PCV2 DNA in serum. In conclusion, this study demonstrated the ubiquity of PCV2 in the Austrian and German boar population. Genetically diverse PCV2 can be encountered in boar semen. Shedder boars cannot be detected on the basis of serology. There is an apparent possibility of PCV2 being transmitted through semen.

Serum haptoglobin concentrations in dairy cattle with lameness due to claw disorders.

In cattle, elevated blood serum concentrations of haptoglobin, an acute phase protein, have been demonstrated in association with several diseases, but not with lameness. Serum haptoglobin was measured in 60 Holstein dairy cattle diagnosed with lameness due to four claw disorders, pododermatitis septica (PS; n=41), pododermatitis circumscripta (PC; n=8), interdigital necrobacillosis (IN; n=7), papillomatous digital dermatitis (PDD; n=4). Haptoglobin was measured on day 1 (0-3 days after lameness was observed but before treatment) and on days 3 and 5. A total of 10 healthy cows served as controls (haptoglobin values <1.0 mg/dL). Each of the claw disorders was associated with elevated haptoglobin on day 1 (PS, PC, IN and PDD: 65.9%, 37.5%, 71.4% and 25.0%, respectively). Trimming and antibiotic treatment led to a reduction in the number of PS and IN cows with increased haptoglobin concentrations, respectively (P<0.05), but trimming did not lead to any reduction in cows with PC. The study showed that lameness due to claw disorders can be associated with a systemic acute phase response and elevated serum haptoglobin in dairy cattle. Based on the course of haptoglobin, treatments seemed effective for all claw disorders except for PC.

Effects of long-term treatment with the GnrH agonist deslorelin (Suprelorin®) on sexual function in boars

Immunization against GnRH has been proven effective for boar taint removal, and long-term treatment with GnRH analogues has been shown to suppress GnRH dependent reproductive processes in several species. This study was conducted to treat boars (n = 5) with Suprelorin, i.e., an implant that contains 4.7 mg of the long-acting GnRH analogue deslorelin, and to test the effects on sexual function. Insertion of the implant occurred at the age of 5 weeks and animals were observed until market age at 26-27 weeks. Surgically castrated (n = 4) and intact boars (n = 3) served as controls. Testes growth was markedly reduced and steroidogenesis (testosterone, estrone, estrone sulphate, estradiol 17beta) as well as spermatogenesis suppressed in 4 of 5 GnRH treated boars, respectively. The remaining fifth boar resumed testes growth after week 17 of age and had high hormone concentrations when tested at weeks 26 and 27. Restoration of spermatogenesis was observed at 34 weeks of age. There were no effects of treatment on general health, nor were there local inflammatory reactions. Results indicate that suppression of sexual functions in boars due to long-term treatment with the GnRH agonist deslorelin through an implant such as Suprelorin is possible and can last for several months up to market age; thus it has potential as an alternative to other methods used for boar taint removal. Because the maximum duration of suppression seems to vary between boars, further studies are necessary to refine the treatment.

Postinsemination treatment of primiparous and multiparous cows with cloprostenol failed to affect ovulation and pregnancy rate in dairy cattle

Previous studies have demonstrated the facilitating effect of a single cloprostenol treatment postinsemination on ovulation and pregnancy rate in dairy cattle and Italian buffalos. This study was conducted to test the effects of 500 microg cloprostenol given intramuscularly immediately postinsemination to 55 primiparous and 60 multiparous Holstein cows (Bos taurus; TR) of a typical dairy operation in East Germany and to compare them with 57 primiparous and 48 multiparous saline-treated cows (CON). Animals of the TR and CON groups did not differ or only differed marginally for age at treatment, interval calving-treatment, lactation number, milk production on the day of treatment, body condition score, and their peri- and postparturient case histories. All animals were clinically and reproductively healthy on the day of treatment. They were inseminated once 12h after the onset of estrus, scanned 24h after insemination to confirm ovulation, and tested for pregnancy by transrectal palpation between Days 42 and 48 postinsemination. Treatment did not affect the number of cows ovulating. The overall combined pregnancy rate (PR) was 47.3%. Pregnancy rate did not differ statistically between TR and CON (46.1% vs. 48.6%; P>0.05). In conclusion, this study failed to demonstrate beneficial effects of a postinsemination treatment of primiparous and multiparous cows with cloprostenol on ovulation and PR in a typical dairy cattle operation in East Germany.

B-mode ultrasound and grey-scale analysis of the epididymis in boars, and the relationship to semen parameters.

This study investigated the epididymis of mature boars (n=10) by means of B-mode ultrasound and grey-scale analysis (GSA) for echogenicity (EG) determination using an ultrasound unit HS 1500V, a linear transducer (frequencies 7.5-9.0 MHz), and standardized unit settings. All boars had their epididymal caput, corpus and cauda scanned six times before and after semen collection, respectively, at weekly intervals. Semen was subjected to spermatological examination including volume, total and forward motility, sperm abnormalities, as well as total sperm count and concentration. The caput and corpus both had a homogeneous fine echotexture. The cauda was homogeneous too but had a marbled echotexture. Echogenicity before and after semen collection was caput > corpus > cauda, respectively (p<0.001). Echogenicity was higher before than after semen collection for all parts of the epididymis, respectively (p<0.001). Echogenicity of the caput correlated slightly positively with the total sperm count pre-collection (r=0.301; p=0.020) and with ejaculate volume pre- and post-collection (r=0.302 vs 0.306; p=0.017 vs 0.019), and slightly negatively with sperm concentration post-collection (r= -0.275; p=0.034). No relationship was found for EG of the corpus and cauda for any of the ejaculate parameters. In conclusion, B-mode ultrasound and GSA proved feasible for imaging the epididymis in boars. Single relationships between EG and ejaculate parameters were found and deserve further investigation.

Analytic validation of commercially available immunoassays for the measurement of serum cobalamin and folate concentrations in pigs

BACKGROUND Cobalamin (vitamin B12 ) and folate (vitamin B9 ) are important for the amino acid metabolism and nucleic acid synthesis. Immunoassays for the measurement of both vitamins in serum are routinely used in people, cats, and dogs, serving as indicators for clinical disorders including cobalamin and/or folate deficiency, small intestinal dysbiosis, or inadequate dietary supply of these vitamins. The analysis of these analytes may also be clinically useful in pigs. OBJECTIVE The purpose of this study was to analytically validate immunoassays for the measurement of cobalamin and folate concentrations in porcine serum, and to determine serum cobalamin and folate concentrations in healthy newborn pigs pre- and postweaning. METHODS Assay validation for both vitamins included the determination of linearity, accuracy, and intra- and inter-assay variability using serum samples from 10 pigs. Also, serum cobalamin and folate concentrations were compared in piglets between pre- and postweaning. RESULTS For both vitamins, observed-to-expected ratios for linearity and accuracy were 93.2 ± 14.3% and 100.3 ± 8.1% (mean ± standard deviation), respectively. Intra- and inter-assay coefficients of variation for serum were ≤ 8.7% and ≤12.5%, respectively. Significantly higher serum cobalamin and lower folate concentrations were observed in piglets at the time of weaning than at postweaning (P < .0061; P < .0001, respectively). CONCLUSIONS Both immunoassays are linear, accurate, precise, and reproducible for measurement of porcine serum cobalamin and folate concentrations. Piglets differing in age by only 12 days had significantly different serum cobalamin and folate concentrations. The implications of differing serum cobalamin and folate concentrations in pigs at different stages of life should be further investigated.