Ergovaline does not alter the severity of ryegrass staggers induced by lolitrem B

AIM: To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline.

METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0–5) weekly during the study. Any animal which was scored ≥4 was removed from the study.

RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41).

CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.     

Methicillin resistant Staphylococcus aureus (MRSA) infection in a dog in the Netherlands

In the Netherlands, methicillin resistant Staphylococcus aureus (MRSA) are regularly isolated from humans. We present the first isolation of MRSA from animal origin in the Netherlands. A coagulase positive staphylococcus was cultured from an infected wound in a Dutch dog that recently underwent surgery abroad. The staphylococcus was resistant to methicillin, ampicillin, amoxycillin + clavulanic acid, cephalexin, erythromycin, lincomycin, tetracycline, gentamicin and enrofloxacin. It was identified as S. aureus by fermentation of mannitol and Martineau-PCR. The presence of mecA was confirmed by PCR.     

Explosive increase in Salmonella java in poultry. Consequences for public health

In the Netherlands S. Paratyphi B variation Java increased in poultry from less than 2% of all isolates before 1996 up to 40% in 2001. This development in poultry runs in parallel with that in Germany and appears not to occur in other European countries. A German study shows that in the late nineties it concerns isolates of only one multi-resistant clone of Java (in Holland as well) whilst isolates before the middle nineties were genetically much more heterogeneous and sensitive to antibiotics. Although the exposition of humans to contaminated poultry meat is relatively high, human patients with a Java infection are rare. Treatment of poultry flocks with quinolones was about 13% in 2000-2001. Resistance to flumequin of Java increased from 3% between 1996-1999 to 20% between 2000-2002 whilst that of other serotypes in poultry remained about 7%. Java is also fast becoming less sensitive to ciprofloxacin which is the antibiotic of first choice in serious cases of salmonellosis. The ministries of public health, agriculture and the production boards, with their research institutes, together with the poultry meat production chain integrations have recently decided to work together in order to determine the public health importance of the Java epidemic in poultry and finding measures for effective control in the poultry industry.     

Akabane disease in sheep

Perinatal lamb mortality, associated with malformations of the CNS due to Akabane viral infection, occurred in 4 of 9 flocks of ewes lambing on 3 farms between 26 May and 14 November, 1976. Cases were restricted to ewes conceiving prior to the second week of March and lambing between 26 May and 19 July. As judged by seroconversion in sentinel flocks on 2 of the farms, field infection with Akabane virus occurred mainly between mid-February and mid-April. Malformations of the CNS occurred in 42.5%, 51.2%, 100% and 31.0% of the dead lambs examined in the affected flocks respectively. Prevalence in the 4 affected flocks, expressed as the proportion of ewes lambing which delivered at least one malformed foetus, was 6.1%, 8.4%, 88.9% and 5.7% respectively. Lamb mortality due to malformations of the CNS was 7.1%, 5.5%, 92.3% and 5.7% of lambs born. Age-specific prevalence was calculated for 3 of the 4 flocks and 2-year-old ewes accounted for 71.4% and 76.9% of total cases respectively in 2 flocks, whereas in one flock malformations occurred at equivalent frequencies throughout several older age groups. Birthweights of affected lambs were usually significantly lighter than those of unaffected lambs of similar sex and birth-type, and their mean duration of gestation was slightly, and significantly, prolonged. Micrencephaly (88.1% of cases) and hydrocephalus (68.7% of cases) were the outstanding pathological features of the malformations with hydranencephaly, microgyria, porencephaly and attenuation of the spinal cord occurring at much lower frequencies.(ABSTRACT TRUNCATED AT 250 WORDS)