Biological control at work: demonstrating the complementary effects of natural enemies on two contrasting pests and the damage they cause

Journal of Pest Science - Natural pest control is a significant service supporting agricultural production. However, the relative contribution of several functional groups of natural enemies to...     

Surgical resection of a gastrointestinal stromal cell tumor by double enterectomy and partial pancreatectomy on a 13-year-old mixed breed dog

Surgical resection of a gastrointestinal stromal cell tumor by double enterectomy and partial pancreatectomy on a 13-year-old mixed breed dog. A 13 year-old, male, mixed breed dog, has been presented for an abdominal mass. The exam showed the presence of an ileo-caeco-colic mass adhered to the distal portion of the pancreas and the mid duodenum. A double enterectomy and a partial pancreatectomy were carried out and a diagnosis of gastrointestinal stromal cell tumor has been established.     

Immune responses after local administration of IgY loaded-PLGA microspheres in gut-associated lymphoid tissue in pigs

Oral vaccination of large animals using PLGA MS (poly(D,L-lactide-co-glycolide)microspheres) appeared to be more challenging than immunization of mice. The purpose of this study was to deliver to GALT an immunogenic model protein (IgY), free or encapsulated by spray-drying in PLGA MS, and to evaluate systemic immune response in SPF Large White pigs. Pigs were surgically processed for local administration of IgY in three sets of experiments. In two sets of experiments, administration was locally performed in temporary ligatured intestinal segments, in jejunal Peyer's patches and in mesenteric lymph nodes. In the third experiment, pigs received IgY via an intestinal cannula. Total IgY-specific antibodies were detected in the sera of pigs after a single local immunization, but not in the sera of cannulated pigs. The study of IgG1 and IgG2 isotypes indicated that PLGA MS are able to elicit a combined serum IgG2/G1 response with a predominance of IgG1 response when locally administered. PLGA MS can be a potential oral delivery system for antigen but our results underlined the difficulty to immunize large animals like pigs. Transposition of data between small and large animals appears to be complex and suggests that physiological features need to be considered to increase intestinal availability of oral encapsulated vaccines.     

Steroid hormone receptors ERα and PR characterised by immunohistochemistry in the mare adrenal gland

Background

Sex steroid hormone receptors have been identified in the adrenal gland of rat, sheep and rhesus monkey, indicating a direct effect of sex steroids on adrenal gland function.

Methods

In the present study, immunohistochemistry using two different mouse monoclonal antibodies was employed to determine the presence of oestrogen receptor alpha (ERalpha) and progesterone receptor (PR) in the mare adrenal gland. Adrenal glands from intact (n = 5) and ovariectomised (OVX) (n = 5) mares, as well as uterine tissue (n = 9), were collected after euthanasia. Three of the OVX mares were treated with a single intramuscular injection of oestradiol benzoate (2.5 mg) 18 – 22 hours prior to euthanasia and tissue collection (OVX+Oe). Uterine tissue was used as a positive control and showed positive staining for both ERalpha and PR.

Results

ERalpha staining was detected in the adrenal zona glomerulosa, fasciculata and reticularis of all mare groups. Ovariectomy increased cortical ERalpha staining intensity. In OVX mares and one intact mare, positive ERalpha staining was also detected in adrenal medullary cells. PR staining of weak intensity was present in a low proportion of cells in the zona fasciculata and reticularis of all mare groups. Weak PR staining was also found in a high proportion of adrenal medullary cells. In contrast to staining in the adrenal cortex, which was always located within the cell nuclei, medullary staining for both ERalpha and PR was observed only in the cell cytoplasm.

Conclusion

The present results show the presence of ERalpha in the adrenal cortex, indicating oestradiol may have a direct effect on mare adrenal function. However, further studies are needed to confirm the presence of PR as staining in the present study was only weak and/or minor. Also, any possible effect of oestradiol treatment on the levels of steroid receptors cannot be determined by the present study, as treatment time was of a too short duration.     

Duodenal obstruction caused by duodenal sigmoid flexure volvulus in dairy cattle: 29 cases (2006-2010)

Objective-To characterize duodenal sigmoid flexure volvulus (DSFV) and determine the prognosis for affected cattle undergoing surgery. Design-Retrospective case series. Animals-29 dairy cattle. Procedures-The medical records were analyzed for history, signalment, clinical signs, medical management, surgical findings, and outcome. Results-29 cattle were determined to have DSFV between December 2006 and August 2010. Twenty cattle had had an omentopexy or pyloropexy performed 1 day to 2 years before initial evaluation. Cattle were afebrile, tachycardic, and moderately dehydrated, with a small zone of percussion with a ping at the 10th to 12th right intercostal spaces and associated succussion. Biochemical changes were a severe hypokalemic (mean ± SD, 2.9 ± 0.5 mmol/L; median, 3.1 mmol/L; range, 2.08 to 3.92 mmol/L), hypochloremic (mean, 69.7 ± 11.1 mmol/L; median, 71.7 mmol/L; range, 49.1 to 94.1 mmol/L) metabolic alkalosis (mean total CO(2), 44.5 ± 7.4 mmol/L; median, 45.3 mmol/L; range, 31.5 to 59.6 mmol/L) and hyperbilirubinemia (mean, 32.4 ± 29.0 μmol/L; median, 20.5 μmol/L; range, 7.8 to 107 μmol/L). Surgical findings for DSFV included an empty descending duodenum adjacent to a dorsally displaced and dilated cranial segment of the duodenum, distended abomasum and gallbladder, and a tight volvulus at the base of the duodenal sigmoid flexure. Manual reduction was considered successful if the descending duodenum filled after cranial duodenal massage. Twenty-two patients were successfully treated; the remaining 7 died or were euthanized within 4 days after surgery. Conclusions and Clinical Relevance-A condition clinically resembling abomasal volvulus but affecting the duodenal sigmoid flexure has been recognized in dairy cattle. When a focal, dorsal right-sided ping and succussion are present combined with severe hypokalemic, hypochloremic metabolic alkalosis and high bilirubin concentration, DSFV should be suspected, especially when there is a history of prior abomasal fixation. After surgical correction, the prognosis is fair to good.     

Sow removal in Swedish commercial herds

The objective of this study was to describe the sow removal pattern in Swedish commercial piglet producing herds, with group-housing of non-lactating sows. The data collection, based on a PC herd monitoring program used in 21 piglet producing herds in the south-central part of Sweden, was prospective, started in 2002 and continued for 3 years. During this period, information on 14 234 removed sows was recorded. For all parameters studied a large variation between herds was found. The average annual removal rate was 49.5% (range 33.6–66.3%). Among the removed sows, 85.2% were sent to slaughter, 10.5% were euthanised and 4.3% were found dead. The most common removal reasons were ‘reproductive disorders’ (26.9%), ‘old age’ (18.7%) and ‘udder problems’ (18.1%), followed by ‘low productivity’ (9.5%), ‘lameness and/or foot lesions’ (8.6%) and ‘traumatic injuries’ (7.1%). The proportion of sows sent to slaughter was higher than the proportion euthanised for all categories of removal except ‘traumatic injuries’ (in which 81.6% of the sows were euthanised). The average parity number at removal for all sows was 4.4. Lowest average parity numbers were found for sows removed due to ‘traumatic injuries’ (2.6). Among removed sows, the proportion removed per parity decreased up to parity 6. Sows removed due to ‘old age’ had the highest piglet production, while sows removed due to reproductive disorders had the highest number of non-productive days (NPD) per parity and the longest interval from last farrowing to removal. With increasing removal parity number, the number of piglets produced increased and NPD decreased. In lower parities (1–3) most sows were removed due to ‘reproductive disorders’, but this proportion fell as parity number rose. Removals due to ‘udder problems’ were most frequent in medium parity numbers (4–6). Most sows removed after parity 7 were removed due to old age. The proportion of the sows found dead was highest just after farrowing; otherwise only a low percentage of sows were removed during the lactation period. The proportion of euthanised sows was high in the week after farrowing and during the 4-week period following weaning. The proportion of sows sent to slaughter increased considerably 4 weeks after farrowing (i.e. after weaning) and stayed high during the subsequent 3 weeks. The study revealed a considerable amount of unplanned removal of young sows. Not only the sows sent to slaughter, but also those euthanised and found dead, must be included in studies on sow removal.     

Studies on the Oestrus and Ovarian Activity During Five Successive Oestrous Cycles in Gilts

The object of the investigation was to study a number of gilts during their first six heats in respect of duration and external signs of oestrus in relation to ovarian function. The study comprised 11 crossbred gilts (Swedish Landrace X Yorkshire). Heat control was done twice daily and comprised a careful inspection of the vulva and check of the standing reflex with and without a vasectomized boar. The ovaries were inspected after the first, third and fifth heats by laparoscopy. Blood samples for progesterone determination were taken once a week during the whole observation period. The genital organs were examined after slaughter.All gilts came in heat regularly during the whole period. Reddening and swelling of the vulva were observed during a significantly longer time in the first and second than in the subsequent pro-oestrous periods. The length of oestrus did not vary significantly in successive heats. The duration of the standing reflex was consistently shorter when the heat control was done in the absence of a boar. All gilts had low progesterone values before their first observed heat. The progesterone level in the blood during the five oestrous cycles studied varied in a cyclical pattern. The number of corpora lutea increased from heat 1 to 5.     

Lessons from Two Case Studies of Implementing Traceability in the Dried Salted Fish Industry

The traceability practices in two companies representative of those in a supply chain—one a producer of wet salted cod, the other of dried salted cod—were systematically investigated by a standard procedure. Neither company retained batch identities for all steps in the production process, and so, they did not have an effective traceability system. Although production of dried salted fish is challenging due to the many transformations taking place during production, the use of the basic technique of applying and recording unique identifiers could have provided a traceability system from delivery of wet fish through to the final dried product. This study focused on the critical points for traceability during production of both wet and dried salted fish and the practical challenges this presented.