The effect of time between doses on serological response to a recombinant multivalent pilus vaccine against footrot in sheep

SUMMARY The response of sheep to a recombinant multivalent footrot vaccine containing pilus antigens was examined after the administration of two doses of vaccine at Intervals ranging from 2 to 52 weeks. Agglutinating antibody titres were measured 3 weeks after the second vaccination and showed that lengthening of the interdose interval results in higher agglutinin titres. The capability of sheep to mount an increasingly strong immune response as the interval between doses is increased provides an opportunity to maximise the usefulness of vaccination by administering the first dose well before an expected footrot transmission period. This advantage of increasing the interdose interval has not been reported for traditional, whole-cell footrot vaccines, and use of the new pilus vaccine in this manner may improve prospects for disease control. Furthermore, sheep given a third dose either 6 or 12 months after their initial two-dose vaccination program achieved significantly higher titres than those elicited after the second dose, suggesting the likelihood of further improvement in disease control in successive seasons.     

Sulfur-associated polioencephalomalacia in cattle grazing plants in the Family Brassicaceae

Polioencephalomalacia was diagnosed histologically in cattle from two herds on the Darling Downs, Queensland, during July–August 2007. In the first incident, 8 of 20 18-month-old Aberdeen Angus steers died while grazing pastures comprising 60% Sisymbrium irio (London rocket) and 40% Capsella bursapastoris (shepherd's purse). In the second incident, 2 of 150 mixed-breed adult cattle died, and another was successfully treated with thiamine, while grazing a pasture comprising almost 100% Raphanus raphanistrum (wild radish). Affected cattle were either found dead or comatose or were seen apparently blind and head-pressing in some cases. For both incidents, plant and water assays were used to calculate the total dietary sulfur content in dry matter as 0.62% and 1.01% respectively, both exceeding the recommended 0.5% for cattle eating more than 40% forage. Blood and tissue assays for lead were negative in both cases. No access to thiaminase, concentrated sodium ion or extrinsic hydrogen sulfide sources were identified in either incident. Below-median late summer and autumn rainfall followed by above-median unseasonal winter rainfall promoted weed growth at the expense of wholesome pasture species before these incidents.     

Haematological, biochemical and selected acute phase protein reference intervals for weaned female Merino lambs

Background   Merino lambs are currently the subject of much research into the welfare aspects of mulesing and mulesing alternatives.
Objective   Obtain haematology, biochemistry and acute phase protein reference intervals using modern methodologies for female Merino lambs.
Method   Blood was collected from 50, weaned, 9- to 16-week-old, female Merino lambs. Haematology and biochemistry panels were performed using routine automated methods. The acute phase proteins, fibrinogen, serum amyloid A and haptoglobin, were also measured using commercially available techniques. The reference intervals were determined to be the central 95% of results.
Results   Differences in the concentrations for some analytes were seen when compared with reported studies in sheep, but may be explained by the use of sheep of a different signalment, as well as different methodologies for analyte measurement. Overall, most analytes gave similar values to those previously reported in other studies. Notable exceptions were alkaline phosphatase, phosphate and globulins, for which the different results were often attributed to the younger age of the sheep in the present study, and platelets and creatine kinase, for which the elevated levels may have been a result of stress and muscle exertion associated with blood collection and husbandry practices.
Conclusion   Established haematological, biochemical and acute phase protein reference intervals are necessary for the investigation of the systemic impact of mulesing and mulesing alternatives and for the investigation of systemic diseases affecting weaned, 9- to 16-week-old, female Merino lambs in general.     

In vitro Release of Ovarian Progesterone is Decreased During the Oestrous Cycle and Pregnancy of Swine with Obesity/Leptin Resistance

Previous studies indicate that reproductive prolificacy of obese swine breeds is markedly influenced by embryo losses in early pregnancy. In such period, adequate secretion of progesterone (P4) by the ovary is essential for pregnancy success. This study analyses the luteal functionality during the oestrous cycle and early pregnancy of Iberian sows and Large White x Landrace females, in terms of P4 secretion after in vitro culture of luteal tissue stimulated or not with luteinizing hormone (LH). The secretion of progesterone (expressed in ng/mg of luteal tissue or ng/mgLT) of the corpora lutea of obese Iberian swine was always hampered when compared to lean genotypes, either during early oestrous cycle (110.7 ± 37.8 vs 259.7 ± 10.2 ng/mgLT; p < 0.0001), late oestrous cycle (49.0 ± 3.5 vs 75.92 ± 7.14 ng/mgLT; p < 0.0001) or early pregnancy (38.4 ± 2.1 vs 70.7 ± 5.3 ng/mgLT; p < 0.0001). The differences in basal P4 secretion remained after stimulation with LH. Finally, P4 secretion during early pregnancy of Iberian sows decreased with age and, hence, with obesity features (46.6 ± 4.2 vs 65.5 ± 4.8 ng/mgLT; p < 0.001). In conclusion, the results of the present study provide convincing evidence of a reduced luteal function during oestrous cycle and early pregnancy of sows with obesity/leptin resistance like Iberian sows, which may contribute to the low reproductive efficiency reported in this breed.     

Fibrous ingluvial foreign bodies in 33 cockatiels (Nymphicus hollandicus)

The presentation, treatment and outcomes of 33 ingluvial fibrous foreign bodies in cockatiels (Nymphicus hollandicus) are described. Vomiting, lethargy and weight loss were the most common presenting signs. Diagnosis was made on palpation of a mass in the crop (ingluvies). Both surgical and non‐surgical treatment regimens were evaluated. The overall mortality rate was 33%, suggesting fibrous materials are not safe for cockatiels to groom or ingest and should not be offered as cage accessories.