Genetic differences in oestrous signs and oestrogen metabolism‐related genes between Chinese Mi and European Landrace‐Large White pigs

Oestrous signs affect timely mating and reproductive efficiency in swine breeding herds. To study the genetic difference of oestrous signs between Chinese and European pigs, 100 Landrace‐Large White (LLW) cross gilts and 50 Chinese Mi gilts were assessed for oestrous signs and the concentrations of serum estradiol‐17β and progesterone were determined. The genotype of 39 single nucleotide polymorphisms (SNPs) in 11 oestrogen metabolism and function‐related genes was determined by Sequenom iPLEX platform. Compared with LLW gilts, Mi gilts had longer time of standing reflex (p < .001), higher scores of vulva reddening (p = .001) and greater serum estradiol‐17β concentration (p < .01). Gilts with greater serum estradiol‐17β concentrations also had greater (p < .05) scores for oestrous signs. Genetic polymorphisms of nine genes in oestrogen metabolism pathways had significant differences (p < .05) between LLW and Mi gilts. There were three and six haploblocks of SNPs in LLW and Mi, respectively. Compared with LLW, the distribution of haplotypes was more centralized in Mi pigs. Genetic polymorphisms of oestrogen metabolism‐related genes have considerable differences between Chinese Mi and European LLW pigs. Because of the important roles of oestrogen during the oestrus, some genes of oestrogen metabolism pathway could be considered as candidate genes for oestrous signs.     

Prevalence of clinical signs of disease in Danish finisher pigs

Between December 1999 and February 2001, two visits, eight weeks apart, were made to 90 herds of Danish finisher pigs. The prevalence of clinical signs was recorded by three veterinary technicians from the Danish Bacon and Meat Council according to a standardised procedure; they had been trained and their observations were monitored and validated before and during the study. A total of 154,347 finisher pigs were examined and 22,136 clinical signs were recorded. Vices accounted for 43 per cent of the signs. The highest mean prevalence was observed for ear necrosis (4.44 per cent), followed by respiratory signs (2.17 per cent), lameness (1.92 per cent), other skin diseases (1.73 per cent), tail bites (1.26 per cent), umbilical hernia (0.78 per cent), flank bites (0.52 per cent), diarrhoea (0.27 per cent), respiratory distress (0.12 per cent), atrophic rhinitis (0.10 per cent), recumbency (0.09 per cent) and central nervous disease (0.05 per cent). The prevalence of atrophic rhinitis was higher in conventional herds than in specific pathogen-free herds. The prevalence of clinical signs of atrophic rhinitis was higher among finishers weighing 51 to 75 kg than among finishers weighing up to 50 kg, and the prevalence of respiratory signs was higher among finishers weighing 51 to 75 kg then among finishers weighing 76 to 100 kg.     

Time‐related changes in post‐operative equine morbidity: A single‐centre study

Our objective was to test the hypothesis that the prevalence and type of post‐operative equine morbidity at a single centre does not change over time with a retrospective and prospective observational study. The post‐operative case records of 92 (of 96) horses undergoing nonabdominal procedures, and surviving to discharge, were compared with previous data from the same centre. Predefined morbidities were recorded from horses undergoing surgery between August 2013 and July 2014. This was compared with data collected from the same institute from April 2004 to June 2005 and published in a previous study. The overall prevalence of morbidities increased from 13.4% to 25%. The prevalence of post‐anaesthetic colic, thrombophlebitis, pyrexia, lameness, neuropathy and myopathy increased while the proportion of incidence of diarrhoea, respiratory distress and wounds sustained in recovery decreased. There was a statistically significant association (P = 0.045) between the duration of surgery and the prevalence of post‐anaesthetic colic. Geldings were less likely (odds ratio 0.12, 95% confidence interval 0.02–0.84) to develop swelling at the catheter site and the likelihood of thrombophlebitis increased by 1.20 (95% confidence interval 1.01–1.41) for every year of life. Tracking morbidities and changes in their prevalence may elucidate their possible causation and allow prophylactic measures to be taken.     

Observer agreement on pen level prevalence of clinical signs in finishing pigs

Four observers performed a standard clinical examination of finisher pigs in two commercial finisher herds. In herd 1, 600 finisher pigs in 44 pens were examined. The observers assessed clinical signs of lameness, umbilical hernia and tail bite according to a standardized procedure. The prevalence of the clinical signs was estimated at the pen level. The procedure was repeated after 3 months in another herd, where 730 finisher pigs in 69 pens were examined. The agreement between observer pairs was assessed using prevalence-adjusted bias-adjusted kappa (PABAK) and proportionate-agreement estimates (P_pos and P_neg).

Observer bias was present despite training and standardization of the participating observers. The highest pen level agreement for the observer pairs was found for pens that had one or more pigs with tail bite (PABAK = 0.82–1.00) and umbilical hernia (PABAK = 0.77–1.00). The agreement was fair-to-moderate for identification of pens holding one or more lame pigs (PABAK = 0.27–0.71). In general, the average agreement of observer pairs on absence of clinical signs (P_neg) was higher than for presence (P_pos). The observer bias varied between observer pairs and with the clinical signs.     

Serum haptoglobin concentration as a marker of clinical signs in finishing pigs

A case-control study of 340 finishing pigs aged 10 to 25 weeks in 15 commercial Danish pig herds was carried out to investigate serum haptoglobin concentration as an objective marker of clinical signs of disease. Pigs with different clinical signs were matched to control pigs without clinical signs with respect to herd, pen, estimated weight and gender, and each pig was subjected to a standard clinical examination. In 86 of the case-control pairs, the rectal temperature was also recorded. There was a significantly higher mean haptoglobin concentration in the serum of lame pigs (P<0.0001), pigs with respiratory disease (P=0.0004), pigs with tail or ear bites (P=0.0004) and pigs with diarrhoea (P=0.02). Similarly, a higher mean rectal temperature was recorded in lame pigs (P<0.0001), pigs with respiratory disease (P=0.002) and pigs with tail or ear bites (P=0.0003). There was a significant but low correlation between rectal temperature and haptoglobin concentration in serum (P=0.003, r=0.20). The area under the receiver-operating-characteristic curve was between 0.67 and 0.78 for the different clinical signs. The maximum simultaneous levels of sensitivity (0.61 to 0.71) and specificity (0.61 to 0.77) of serum haptoglobin for the different clinical signs were obtained at a cut-off value of 1.1 mg/ml. At a cut-off value of 1.8 mg/ml, the sensitivity decreased to 0.31 to 0.60, and the specificity increased to 0.82 to 0.86. It was not possible to define a cut-off value which classified individual pigs according to their clinical signs.     

Pathogenesis of sodium selenite and dimethylselenide acute toxicosis in pigs: Cardiovascular changes

In pigs and other food producing animals, relatively little is known about the mode of action of excess selenium. This study reports the cardiovascular effects brought about in anaesthetised Landrace pigs by 2 mg selenium kg-1 bodyweight intravenously as either sodium selenite or dimethylselenide. Sodium selenite dosing was characterised by a dramatic fall in systemic blood pressure with an increase in cardiac output and heart frequency. The only significant change elicited by dimethylselenide was a linear rise of cardiac output. Neither of the tested compounds significantly affected pulmonary arterial pressure. These results suggest that under the experimental conditions in this study, sodium selenite induces a vasculogenic shock without primarily affecting cardiac performance. The lack of detrimental effects on cardiovascular parameters with dimethylselenide indicates the importance of methylation in detoxifying excess selenium.     

Risk factors for clinical signs of PMWS and PDNS in pigs in The Netherlands: a case-control study

Potential risk factors for clinical signs of post-weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS) in pigs in the Netherlands were investigated in a matched case-control study using a questionnaire (personal interview). Eighty-two pig farmers were questioned about management, hygiene, husbandry systems, disease history, and preventive health care. In this study, 30 pig herds with (cases) and 30 pig herds without (controls) characteristic clinical signs of PMWS were compared. For PDNS, 11 pig herds with (cases) and II pig herds without (controls) characteristic clinical signs of PDNS were compared. Univariate analysis (P < 0.10) showed that the following occurred relatively more often in the PMWS case herds than in the control herds: 1) clinical signs of PDNS, porcine reproductive and respiratory syndrome (PRRS), porcine parvovirus (PPV) infections, meningitis, coccidiosis, and pre-weaning diarrhoea observed by the farmer; 2) vaccination against PRRS and mycoplasma; 3) non-optimal climatic conditions in the nursery rooms, a large variation in weaning age, a high occurrence of cross-fostering of piglets, a large number of sows with lactation problems, poor colostrum intake by piglets; and 4) (historical) use of breeding stock (including semen for artificial insemination) of Anglo-Saxon origin. In the final multivariate statistical model, one variable remained significantly associated with PMWS case herds, namely, the presence of clinical signs of PRRS (and/or the associated use of vaccination against PRRS). It should be noted that in almost all cases animals were vaccinated against PRRS because of clinical signs of PRRS that appeared a few months after the first occurrence of clinical signs of PMWS. This excludes PRRS vaccination as a primary factor in causing PMWS. Analysis of the PDNS case-control data showed comparable results with those of the PMWS study. In the final statistical model, the presence of clinical signs of PRRS (and/or the associated use of vaccination against PRRS) was significantly associated with PDNS case herds.     

Gastric displacement in dogs without clinical signs of acute dilatation

Radiographs from four dogs with non-specific signs of digestive disturbances showed displacement of the fundus and pylorus corresponding to a 180^o rotation of the stomach. All the dogs belonged to breeds with a high incidence of typical gastric torsion with dilatation. The possible importance of this gastric instability in the development of an acute attack of gastric torsion is discussed.     

Value of the clinical examination in diagnosing enzootic pneumonia in fattening pigs

The diagnosis of enzootic pneumonia at the herd level should be based on a combination of different methods. Currently, clinical examination is usually considered to be a low value method, particularly compared to the direct detection of Mycoplasma hyopneumoniae in lung lesions by PCR. The present study compared the value of accurate clinical examination (including the quantitation of coughing), PCR on bronchoalveolar lavage fluid, and serological testing of blood samples for the purpose of diagnosing enzootic pneumonia. The coughing index (average % of pigs coughing per minute of observation) was determined in fattening pigs from 59 herds, and ranged from 0% to 6.7% with a median of 2.4%. Five hundred and ninety bronchiolar lavage samples and 1179 serum samples were taken from pigs in those 59 herds and tested for M. hyopneumoniae specific DNA and antibodies, respectively. In herds where ?50% of lavage fluids were PCR positive, the likelihood of a higher coughing index was increased by 76% (OR: 1.76; 95% CI: 1.14-2.72) compared to herds with <50% of positive samples. For antibodies (determined by ELISA) a seroprevalence of ?50% increased the likelihood of a high coughing index by 50% (OR: 1.50; 95% CI: 1.03-2.20). In 78.1% of all herds with a seroprevalence of ?50% against M. hyopneumoniae, the PCR-prevalence and the coughing index were above the median (50% and 2.4%, respectively). It was concluded that in fattening pigs a quantitative assessment of the onset of coughing - typically dry and non-productive - improves the diagnosis of enzootic pneumonia and can occasionally substitute for the detection of M. hyopneumoniae by PCR.