Comparison of Gaseous and Water-Based Medium-Expansion Foam Depopulation Methods in Cull Sows

The U.S. swine industry is currently inadequately prepared to counteract the increasing threat of high-consequence diseases. Although approved and preferred depopulation guidelines exist, ventilation shutdown (VSD+) is currently the only method being deployed during a state of emergency to depopulate large swine populations. However, the permitted use of VSD+ during constrained circumstances has been criticized due to raised swine welfare concerns. The objective of this study was to investigate the effectiveness of carbon dioxide gas (CO2), nitrogen gas (N2), compressed air foam (CAF), compressed nitrogen foam (CAF-N2) and aspirated foam (AF) during a 15-min dwell time on adult swine in an emergency depopulation situation. A small-scale trial using 12 sows per depopulation method showed the highest efficiency to induce cessation of movement for AF and CO2 (186.0 ± 48 vs. 202.0 ± 41, s ± SD). The ease of implementation and safety favored AF for further investigation. A large-scale field study using AF to depopulate 134 sows in modified rendering trailers showed a mean fill time of 103.8 s (SD: 5.0 s) and cessation of movement of 128.0 s (SD: 18.6 s) post filling. All sows were confirmed dead post-treatment for both trials. The implementation of AF in modified rendering trailers may allow for a safe and reliable method that allows for the expedient and mobile depopulation of both small and large numbers of sows during an emergency.

Causes of death of sows in three Brazilian pig farms

ABSTRACT: Sow mortality is directly related to financial losses and productive efficiency in pig farms. Despite this, diseases associated with the death of sows are poorly understood. This study aimed to determine the main causes of death of sows in Brazilian pig farms. To perform this research, three Brazilian pig farms were visited, and necropsies were performed on all sows that had died spontaneously or were subjected to euthanasia. Tissue fragments were collected for histopathological and bacteriological examination. In addition, the clinical signs, productive stage, parity, and type of death (spontaneous or euthanasia) were recorded. A total of 138 necropsies were performed, and 132 had a conclusive diagnosis. The most frequent productive stages were gestation and lactation (33.3 and 31.9%, respectively), followed by parturient sows (17.4%), cull sows (9.4%), weaning-to-estrus interval (WEI) (4.3%), and unmated gilts (3.6%). The most affected organ systems were reproductive (28%), digestive (25%), locomotor (22%), cardiovascular (9.1%), and hematopoietic (6.1%). The most frequently diagnosed conditions were uterine prolapse (16/132; 12.1%), gastric ulcer (13/132; 9.8%), suppurative arthritis (11/132; 8.3%), liver lobe torsion (11/132; 8.3%), heart failure (9/132; 6.8%), vaginal or vaginal and rectal prolapse (9/132; 6.8%), and pododermatitis (8/132; 6.1%). Although 58.2% of the deaths were due to one of these seven diseases, there was a great variability in diagnoses.

Planimetric Determination of the Static Space of Cull Sows as the First Step towards a Recommendation of Loading Densities for Cull Sows during Road Transportation in the European Union

The available floor space is an important welfare factor for cull sows during transportation. Sows of modern genetics reach a size and weight far exceeding those of fattening pigs. In most countries, there are no binding, consistent regulations for the maximum loading densities, especially for sows during road transportation. As a first step towards such recommendations, the physical floor space requirement (static space) of 100 sows of a current breed, while standing and lying down, were determined using contrast-based planimetry. An average sow covered about 0.42–0.47 m2 (standing postures) up to 0.53–0.63 m2 (lying postures). The largest measured area was 0.72 m2 for a sow lying in the belly-chest position. We detected a significant dependency of the covered floor area and the live weight, which supports the common practice to derive space requirements and recommendations based on live weight. Also, our results suggest that especially heavy sows, under currently usual loading densities, are at risk of having insufficient floor space requirements during transport. The results cannot be used to define the space required by a sow to carry out movements or sustain the individual need for distance (social/dynamic space) but provide data on the static space covered by sows of current breeds.

Cases of high mortality in cull sows and feeder pigs associated with Streptococcus equi subsp. zooepidemicus septicemia

Investigations of 2 cases of high mortality in cull sows and feeder pigs from a buying station in Ohio and cull sows at an abattoir in Tennessee were conducted at the Iowa State University Veterinary Diagnostic Laboratory. The animals were presented as weak, lethargic, and some with high fever. Rapidly escalating mortality was reported to be as high as 30–50% within groups at the buying station over 8–10 d, and 30–40% over 5–7 d at the abattoir. Splenomegaly and red lymph nodes were the most consistent macroscopic findings, with scant fibrinous polyserositis observed in one sow. The microscopic lesions of vasculitis, fibrin thrombi, fibrinosuppurative polyserositis, and intralesional bacteria were consistent with acute bacterial septicemia. Bacterial culture isolated Streptococcus equi subsp. zooepidemicus ( S. zooepidemicus) from multiple organs, including spleen, lung, and kidney. PCR tests were negative for African swine fever virus, classical swine fever virus, Erysipelothrix rhusiopathiae, porcine reproductive and respiratory syndrome virus, porcine circovirus 2, and Salmonella spp. Porcine circovirus 3 was inconsistently detected at low levels by PCR, with a lack of associated lesions. Next-generation sequencing identified S. zooepidemicus and porcine partetravirus in the serum sample of the feeder pig from the buying station. Phylogenetic analysis of the szP gene indicated that the S. zooepidemicus isolates from Ohio and Tennessee are in genotype VI. We conclude that the cause of these high mortality events in swine was S. zooepidemicus septicemia.

Significant variation in the management of cull sows before transport for slaughter: results from a survey of Danish pig farmers

BackgroundApproximately 50% of sows are slaughtered each year, but management of cull sows is not well described.MethodsWe aimed to describe how cull sows are sent to slaughter using a questionnaire survey emailed to 885 Danish pig farmers, including questions about the use of pick-up facilities (either a designated pen used for reasons of biosecurity and practicality, in a special part of the barn, where pigs are kept in the last hours before being loaded onto a commercial truck, or a stationary vehicle kept outside the buildings and used for the same purpose) and evaluation of fitness for transport.ResultsA total of 360 farmers answered all questions, constituting a homogeneous group of middle-aged, experienced males. The management of the sows seemed rather variable, for example regarding choice of pick-up facility, its available resources, actions taken when sows were not fit for transport and sow conditions leading to doubt about fitness for transport. Special condition transport was only reported rarely, and rejection of sows due to lack of fitness for transport, by drivers or veterinarians at the slaughterhouse, was only rarely experienced.ConclusionThese findings may be used for formulation of hypotheses for future studies in this area characterised by welfare challenges, potentially leading to science-based recommendations relevant for animal welfare, productivity and biosecurity.