Review: Assessment of completeness of reporting in intervention studies using livestock: an example from pain mitigation interventions in neonatal piglets.

Accurate and complete reporting of study methods, results and interpretation are essential components for any scientific process, allowing end-users to evaluate the internal and external validity of a study. When animals are used in research, excellence in reporting is expected as a matter of continued ethical acceptability of animal use in the sciences. Our primary objective was to assess completeness of reporting for a series of studies relevant to mitigation of pain in neonatal piglets undergoing routine management procedures. Our second objective was to illustrate how authors can report the items in the Reporting guidElines For randomized controLled trials for livEstoCk and food safety (REFLECT) statement using examples from the animal welfare science literature. A total of 52 studies from 40 articles were evaluated using a modified REFLECT statement. No single study reported all REFLECT checklist items. Seven studies reported specific objectives with testable hypotheses. Six studies identified primary or secondary outcomes. Randomization and blinding were considered to be partially reported in 21 and 18 studies, respectively. No studies reported the rationale for sample sizes. Several studies failed to report key design features such as units for measurement, means, standard deviations, standard errors for continuous outcomes or comparative characteristics for categorical outcomes expressed as either rates or proportions. In the discipline of animal welfare science, authors, reviewers and editors are encouraged to use available reporting guidelines to ensure that scientific methods and results are adequately described and free of misrepresentations and inaccuracies. Complete and accurate reporting increases the ability to apply the results of studies to the decision-making process and prevent wastage of financial and animal resources.

Prevalence of selected enteropathogenic bacteria in Hungarian finishing pigs.

The aim of this study was to obtain prevalence estimates about the most important enteropathogenic bacteria: Lawsonia intracellularis, Brachyspira hyodysenteriae, Brachyspira pilosicoli, Salmonella enterica and Clostridium perfringens A and C in Hungarian farrow-to-finish pig herds. A total of 31 herds were selected, from where six pooled faecal samples, each containing three individual rectal faecal samples were collected from fattening pigs of 5-6 months of age. All 186 samples were examined by polymerase chain reaction (PCR) for the presence of the pathogens mentioned above. Lawsonia intracellularis was found in 29 herds (93.55%) and in 108 samples (58.06%); B. hyodysenteriae in 14 herds (45.16%) and in 23 samples (12.37%); B. pilosicoli in 19 herds (61.29%) and in 53 samples (28.49%); S. enterica in 17 herds (54.83%) and in 40 samples (21.50%). We detected the presence of C. perfringens A in 19 herds (61.29%) and in 46 samples (24.73%), while C. perfringens C was found in 8 herds (25.81%) and in 11 samples (5.91%). All examined herds were infected with one or more of these agents. Herds with diarrhoea in the mid- to late finishing phase had almost 10 times higher prevalence of B. hyodysenteriae than herds without such a history.

Effect of vitamin supplements on some aspects of performance, vitamin status, and semen quality in boars.

The aim of the present study was to determine the effects of dietary supplements of vitamins on vitamin status, libido, and semen characteristics in young boars under normal and intensive semen collection. Sixty Landrace, Yorkshire, and Duroc boars were allocated randomly from 6 to 10 mo of age to one of the following diets: 1) basal diet (industry level) for minerals and vitamins (Control, n = 15); 2) basal diet supplemented with vitamin C (ASC, n = 15); 3) basal diet supplemented with fat-soluble vitamins (FSV, n = 15); and 4) basal diet supplemented with water-soluble vitamins (WSV, n = 15). After puberty (approximately 12 mo of age), semen was collected at a regular frequency (three times every 2 wk) for 5 wk. Thereafter, all boars were intensively collected (daily during 2 wk). A recovery period (semen collection three times every 2 wk) followed and lasted for 10 wk. Sperm quality (percentage of motile cells and percentage of morphologically normal cells) and quantity (sperm concentration, semen volume, and total sperm number) were recorded as well as direct and hormone related measurements of boar libido. Blood and seminal plasma samples were taken to monitor vitamin status. High concentrations of B6 (P < 0.05) and folic acid (P < 0.05) were observed in the blood plasma of WSV boars, whereas greater concentrations of vitamin E (P < 0.01) were obtained in FSV boars. In the seminal plasma, folic acid concentrations tended to be greater in WSV boars (P < 0.08). During the intensive collection period, there was a tendency (P < 0.06) for semen production to be greater in WSV boars, the effect being less pronounced (P < 0.10) in FSV boars. During the recovery period, the percentage of motile sperm cells was greater in WSV boars (P < 0.03) and, to a lesser extent, in FSV boars (P < 0.10) compared with Control boars. Sperm morphology and libido were not affected by treatments. These results indicate that the transfer of vitamins from blood to seminal plasma is limited and the dietary supplements of water-soluble and fat-soluble vitamins may increase semen production during intensive semen collection.

Effects of repeated cross-fosterings on preweaning behavior and growth performance of piglets and on maternal behavior of sows.

Extensive cross-fostering is widely used in early-weaning units in order to standardize and improve body weight at weaning. However, young suckling piglets develop teat fidelity and repeated cross-fosterings could go against this behavior. This experiment was therefore conducted to compare the behavior and growth of 13 control and 14 fostered litters. Once every 3 d (from d 1 to 16 of lactation), all piglets were weighed and three piglets were switched between two fostered litters. Their unfostered littermates were called residents. Behavior was recorded for 2 h after weighing and(or) adoption and during one nursing period 24 h later. Fights were more frequent (P < 0.05) in treated than in control litters during and between nursings at all ages of adoption except d 1. Most fights occurred between resident and fostered piglets (P < 0.001), except at d 1. Fights during nursing were still more frequent in treated than in control litters 24 h after adoption (P < 0.02), except at d 1 and 16. More piglets had skin lacerations in treated than in control litters except at d 1 (P < 0.05), and scratches were more frequent in fostered than in resident piglets at d 1 (P = 0.07), 7, 13, and 16 (P < 0.01). At all ages except d 1, failed nursings and snaps at piglets were more frequent in fostered than in control litters (P < 0.05), most snaps being directed at adopted piglets (P < 0.001). In fostered litters, sows spent 15 to 30% less time lying on their sides at d 4, 7, 13, and 16 (P < 0.05). Finally, adopted piglets were 13% lighter than controls at weaning (P < 0.001), whereas residents were heavier than adopted piglets (P < 0.05) but lighter than controls (P = 0.1). These data demonstrate that cross-fostering done repeatedly during lactation is stressful for piglets and sows and does not improve body weight at weaning.

Epidemiological, clinical and control investigations on field porcine coccidiosis: clinical, epidemiological and parasitological paradigms?

For several reasons, we are convinced that the parasitologist community must look again at porcine neonatal coccidiosis. We find it surprising that this disease is seldom addressed, and that assumptions are not always supported by clinico-epidemiological analysis. For example, the relationship between diarrhoea and the excretion of oocysts during experimental infection versus field infection is not questioned. Lindsay et al. review parasitological knowledge of this disease in the latest (1999) edition of Diseases of swine. Although this paper is divided into two parts, we have three distinct objectives: (1) to bring to the debate our experience in the medical control of this disease; (2) to propose a diagnostic methodology; (3) to raise some questions on various clinical, epidemiological and parasitological unknowns.

Sensitivity of reproducing sows and suckling pigs to stray voltage.

OBJECTIVE: To evaluate whether stray voltage reduces welfare of sows and their litters, causes reproductive problems, or impairs growth and survival of suckling pigs. ANIMALS: 120 gilts assigned randomly to 3 treatment groups: 2-V baseline plus 3-V pulses (2-5 V); 5-V baseline plus 3-V pulses (5-8 V); and control treatment (0-0 V). PROCEDURE: Behavior was recorded during gestation and lactation. Water and feed intakes were measured daily, milk composition was evaluated once during lactation, and hematocrit, hemoglobin, glucose, total protein, aspartate transaminase, alanine transaminase, albumin, globulins, and fatty acids values were measured at mating, weeks 8 and 15 of gestation, parturition, and weaning. Prolific ability of sows, mortality and disease of suckling pigs, and growth rate until 56 days of age were recorded. RESULTS: Gilts under voltage were lying down more often and performing less abnormal behaviors than were control gilts. Behavior of sows and suckling pigs was not affected by treatments. Water and feed intakes were similar among treatments, except during week 1 of lactation where feed intake was lower in the control group. Fecundity and prolific ability of sows, percentage of stillbirth, growth rate of suckling pigs, and milk composition were similar among treatments. More suckling pigs died in 2-5-V group than in other groups, but diarrhea was more frequent in the control group. Blood metabolites were similar among treatment groups. CONCLUSIONS: Transient stray voltage at values up to 8 V did not impair the welfare, reproductive performance, or health of sows and suckling pigs.

Serum concentrations of micronutrients, packed cell volume, and blood hemoglobin during the first two gestations and lactations of sows.

The objective of the present work was to describe the changes in serum concentrations of some micronutrients during the first 2 gestations and lactations of 33 gilts in order to establish blood reference values for a rapid assessment of nutritional status. In both parities, blood samples were taken from the jugular vein at mating, 5, 10 and 15 wk of gestation and l d and 4 wk after parturition (weaning). Reference values (mean, standard deviation, minimum, maximum) for serum folates, vitamin B12, vitamin B6 metabolites (pyridoxal and pyridoxal-5-phosphate), calcium, phosphorus, sodium, zinc, copper and iron, as well as blood hemoglobin and packed cell volume are reported for each studied time. Differences between parities and between each time are also reported. Results from the present report demonstrate that knowledge of the physiological state of the sows is critical for the assessment of nutritional status of an individual or a breeding herd by interpretation of analyses of blood constituents.

Detection of cervical bacterial contamination in swine by two methods of swabbing in relation to artificial insemination.

Factors associated with uterine contamination during artificial insemination (AI) are not well defined. A frequently imputed risk factor is vulvar hygiene, although its role has never been assessed objectively. The aim of this study was to identify an objective marker of hygiene during AI and to assess the impact of vulvar hygiene on cervical contamination. In a herd in a depopulation-repopulation process, 68 paired sows of each parity were divided into 2 treatment groups. Before 2 sham AIs, with a 24 hour interval, control sows (CTR) had their vulva cleaned and treatment sows (TRT) had theirs soiled with feces. After the 2nd sham AI, swabbings were taken from the spirette and from the cervix. Bacterial growth was assessed by a semiquantitative method, and aerobic bacterial species identified. The discordance between the paired data was assessed by a McNemar chi-square test. No difference in gram-positive bacterial counts between the 2 groups was found using the cervical swab (P > 0.05). The presence of trace colonies of Escherichia coli were, however, more frequent in TRT (P < 0.05). The spirette showed a greater contamination for mixed flora of bacterial species such as E. coli (P < 0.001) and non-S. suis streptococci (P < 0.05) in TRT sows. A light cervical E. coli growth was more frequent when the vulva had been soiled. Bacterial flora on the spirette following AI may be used as an objective and practical indicator of vulvar hygiene during AI in sows.

Gentamicin pharmacokinetics in newborn and 42-day-old male piglets.

The pharmacokinetics of gentamicin was investigated in six newborn male piglets, aged from 4 to 12 h at the time of administration of the drug, and six 42-day-old castrated male piglets, that had been weaned for 2 weeks following a single intravenous bolus of 5 mg/kg. Gentamicin was measured in serum and in urine by a fluorescence polarization immunoassay. The serum concentration-time data were best described by a three-compartment open model. A rapid initial distribution phase (pi phase) was observed in every animal. The serum beta half-life (t 1/2 beta) was significantly longer in the newborn piglets (mean +/- SEM) (5.19 +/- 0.30 h) than in the older group (3.50 +/- 0.23 h) (P < 0.05). Mean residence time was similarly longer in younger piglets (6.62 +/- 0.57 h) than in older animals (2.86 +/- 0.11 h) (P < 0.05). The steady-state volume of distribution (Vdss) was significantly larger for younger pigs (0.785 +/- 0.036 L/kg) than in elder pigs (0.474 +/- 0.029 L/kg) (P < 0.05). Urinary gamma half-life (t 1/2 gamma u) was 72.66 +/- 10.78 h in the newborn piglets and 69.20 +/- 14.77 h in the 42-day-old animals. A urinary delta phase was observed in three of the 42-day-old piglets and gave a mean t 1/2 delta u of 232.01 +/- 14.55 h. Percentages of urinary recovery of the administered dose after 144 h were 94.18 +/- 1.01 and 94.04 +/- 1.12 in the newborn and 42-day-old animals, respectively. Serum gentamicin clearance was significantly lower in younger animals (0.121 +/- 0.007 L/h.kg) than in the 42-day-old group (0.166 +/- 0.010 L/h.kg). It is suggested that in the newborn piglets, the increase of Vd(SS) could be explained by a higher proportion of extracellular water while the lower clearance could be attributed to a reduced glomerular filtration capacity. Gentamicin dosage requirement in the newborn piglets would therefore have to be adjusted, in order to take into consideration the observed differences in the man values of these latter pharmacokinetic parameters.

Influence of vulvar hygiene on cytology of vaginal smears after sham artificial insemination in sows.

The description of vaginal cytology in the sow in relation to artificial insemination (AI) has never been reported. Poor vulvar hygiene is frequently imputed as a cause for the development of endometritis after AI and could thus enhance the inflammatory response of the genital tract. The goal of this study was to use cytology as an objective tool to evaluate the vulvar hygiene during sham AI. Sixty-eight sows were matched according to their parity and week of mating and divided into 2 groups: treatment sows (CVS) had their vulva cleaned with a 1:2000 Hibitane solution and control sows (SVS) had theirs soiled with feces. Both groups of sows were inseminated twice with saline following this vulvar treatment, once at detection of estrus and a 2nd time 24 hours later. Vestibular smears were taken before each AI, and vaginal smears were taken after each AI from the material present on the insemination spirette. Cytological smears were described by the predominant type of cells, namely epithelial, neutrophil, or no predominance. Results showed no significant differences between the 2 groups and no evolution in the predominance of neutrophils from the 1st to the 2nd AI (P > 0.05). The pooled results from the 2 groups showed an increase in cellularity from the 1st to the 2nd AI (P > 0.05). Neither the cellularity nor predominant cell type in vestibular or vaginal smears from estrus sows are predictors of vulvar hygiene during sham AI (P > 0.05).

Effect of bulky diets based on wheat bran or oat hulls on reproductive performance of sows during their first two parities.

The aim of the present study was to determine the effect of different degrees of bulkiness in the gestation diet on reproductive performance of sows during their first two parities. The density of the diets was modified by incorporating a high proportion of fibrous ingredients (wheat bran and corn cobs in Diet 2 and oat hulls and oats in Diet 3). A diet without fibrous ingredients was used as a control (corn and soybean meal in Diet 1). Although all the gestation diets were formulated to provide the same daily intake of the major nutrients, sows fed Diet 3 were the lightest and had the lowest backfat thickness (P < or = .05) during both parities, and those fed Diet 2 were the heaviest and the fattest (P < or = .05) during the second parity. These results seem to indicate an overestimation of the calculated nutritive value of Diet 3, whereas those obtained with Diet 2 seemed to be linked to its marked effect on behavior of sows during the second parity. There was no marked effect (P > .11) of treatments on the number of pigs born alive, on preweaning mortality, or on the weaning-to-estrus interval. At parturition, total litter weight was similar among treatments in the first parity, whereas in the second parity it was greater (P < or = .05) in sows fed Diet 2 than in those fed Diets 1 and 3. In both parities, feed intake of the common lactation diet given during lactation was 5% higher (P < or = .05) for sows fed Diet 3 during gestation than for sows fed the other diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Reconciling productivity and welfare in intensive pig husbandry: a challenge for the year 2000.

In the first part of this paper, the authors discuss the growing concern of consumers for farm animal welfare, and the attitude adopted by veterinarians to cope with this new and more humanitarian concept of intensive husbandry. The effects of intensification of pig production on the ability of pigs to adapt, and the behavioural, husbandry and health consequences of the principal stress factors in pig rearing are reviewed and illustrated by examples from recent research. In conclusion, the authors discuss the importance of constructive integration of welfare into pig production, in training courses and in actual application.

Comparison of isolation methods for the recovery of Bordetella bronchiseptica and Pasteurella multocida from the nasal cavities of piglets.

Nasal swabs from 241 piglets from 12 herds with clinical atrophic rhinitis and 283 piglets from 14 herds without clinical atrophic rhinitis were examined for the presence of Bordetella bronchiseptica and/or Pasteurella multocida. For B. bronchiseptica, swabs were streaked on three selective media. Blood agar supplemented with cephalexin was the most satisfactory selective culture medium for the isolation of B. bronchiseptica. For P. multocida, swabs were also streaked on three selective media. Mice were also used for isolation of P. multocida from the nasal cavities of pigs. The mouse inoculation test was not found to be the definitive test for the isolation of P. multocida. A significant number of P. multocida strains were avirulent in the mouse model. The modified Knight medium (without potassium tellurite) was the best single method for isolating P. multocida. However, a combination of mouse passage and direct culture on selective media increased the rate of isolation. There was no marked difference in the prevalence of B. bronchiseptica or P. multocida in swine herds with or without clinical atrophic rhinitis. Both capsular types A and D were present in the nasal cavities of the pigs with or without clinical atrophic rhinitis.

Transient stray voltage: is it detrimental to growth performance, health status and welfare of market pigs?

The effects of transient stray voltage associated with an alternating current were evaluated in growing-finishing pigs from 9 to 22 weeks of age. Seventy-two pigs were assigned to 9 blocks of 8 animals each. In each block, the following treatments were randomly distributed: a constant voltage differential created between the feeder or drinker and the metallic floor (woven wire), at a level of 0 volt plus 2-volt pulses (0 V-2 V), 2 volts plus 3-volt pulses (2 V-5 V), 5 volts plus 3-volt pulses (5 V-8 V), and a control treatment without any voltage differential (0 V-0 V). The constant voltage was applied 24 h per day. The pulses of 3 s duration were in the form of an increase in the amplitude of the constant 60-Hz signal. One pulse appeared every 20, 40 and 100 s during the hour following feed distribution and every 60, 120 and 300 s during the rest of the day. The animals were fed ad libitum and received fresh feed twice per day. Once during the 2-week periods at 9-10, 13-14, 17-18 and 21-22 weeks of age, the behaviour of the pigs was recorded during the hour following the two daily feed distributions. Animal weights and blood samples were taken every 2 weeks, from 9 to 21 weeks of age. No significant effect of transient stray voltage on any of the variables measured for the feeding, drinking, sitting or lying activities was found (p > 0.05). At 9-10 weeks of age, the number of rooting bouts was higher for the 5 V-8 V treatment (p = 0.03) and the number of events of butting the penmate was higher for the 2 V-5 V treatment (p = 0.05). Although the water and feed intake did not differ between treatments (p > or = 0.39), the average daily gain of the control group was lower than that of treated groups (p = 0.04) at 9 and 10 weeks of age, while the pigs submitted to a 2 V-5 V treatment had a higher daily gain than the pigs in the other treatment groups (p = 0.05) at 17 and 18 weeks of age.(ABSTRACT TRUNCATED AT 400 WORDS)

Swine reproductive and respiratory syndrome in Québec: Isolation of an enveloped virus serologically-related to Lelystad virus.

Sera were collected from convalescent sows and sick piglets from six pig farms in southern Quebec that have experienced outbreaks of the so-called porcine reproductive and respiratory syndrome. By indirect immunoperoxidase, a few of these sera (4 of 14) (28.6%) were found to be positive for antibody to the Lelystad virus, whereas by indirect immunofluorescence 30 of 36 (83.3%) were positive for antibody to the antigenically-related American isolate ATCC-VR2332. Pregnant sows inoculated intranasally with filtered homogenates prepared from the lungs of necropsied piglets obtained from a seropositive farm developed fever, inappetence, and reproductive failure characterized by stillbirths and various stages of mummification. Lesions of interstitial pneumonia were induced in experimentally-infected specific pathogen-free piglets. A virus, having morphological and biological characteristics of viruses assigned to the family Togaviridae, was isolated from lung tissues of experimentally-infected animals; it could only be propagated in primary cultures of porcine alveolar macrophages. Identification of the virus was confirmed by indirect immunofluorescence using a monoclonal antibody directed against the nucleocapsid protein of the ATCC-VR2332 isolate and porcine sera that were found positive for antibody to both the Lelystad and ATCC-VR2332 isolates.

Pathogenesis, prevention, and treatment of lactational insufficiency in sows.

Lactational insufficiency is one of the major problems in swine production, and the consequences on the growth of the litter must be emphasized. Pathophysiology involves neuroendocrinologic interactions and the role of target organs such as the mammary glands, uterus, bladder, and gut. The complexity of these interactions and the fact that all interactions are not well understood leads to a broad approach. Some risk factors and their associations with lactational insufficiency are described to help the practitioner in the clinical approach to such a problem.

Antigenic variant of swine influenza virus causing proliferative and necrotizing pneumonia in pigs.

A new antigenic variant of swine influenza virus was isolated from the lungs of pigs experiencing respiratory problems in 7 different swine herds in Quebec. Pigs of different ages were affected, and the main clinical signs were fever, dyspnea, and abdominal respiration. Coughing was not a constant finding of the syndrome. At necropsy, macroscopic lesions included the overall appearance of pale animals, general lymphadenopathy, hepatic congestion, and consolidation of the lungs. Histopathologic findings were mainly proliferative pneumonia with a significant macrophage invasion, necrotic inflammatory cells in the alveoli and the airways, a marked proliferation of type II pneumocytes, and thickening of the alveolar septae. Fluorescent antibody examination of lungs of sick piglets did not demonstrate porcine parvovirus, transmissible gastroenteritis virus, or encephalomyocarditis virus. However, evidence of the presence of an influenza type A infection was demonstrated by indirect immunofluorescence (IIF) staining using monoclonal antibody directed to nucleocapsid protein (NP) of human type A influenza virus. The virus was isolated either by intra-allantoic inoculation of specific-pathogen-free embryonating hens' eggs or propagation in canine kidney (MDCK) cells in the presence of trypsin. By hemagglutination inhibition tests, no cross-reactivity was demonstrated with human influenza H1N1, H2N2, and H3N2 strains, and infected MDCK cells did not react by IIF with monoclonal antibodies to NP protein of type B influenza virus. The hemagglutination activity of plaque-purified isolates was only partly inhibited by hyperimmune serum produced to subtypes A/Wisconsin/76/H1N1 and A/New Jersey/76/H1N1 of swine influenza virus. Gnotobiotic piglets that were infected intranasally with egg-adapted isolates of this new antigenic variant of swine influenza virus developed the very same type of lesions observed in field cases.

Characterization of Pasteurella multocida from nasal cavities of piglets from farms with or without atrophic rhinitis.

A total of 137 strains of Pasteurella multocida isolated from the nasal tracts of pigs with and without clinical atrophic rhinitis (AR) were studied for their biochemical, antigenic, and toxigenic characteristics. There were no major biochemical differences among the P. multocida isolates. Capsular antigen types A and D were both present in the nasal cavities of the pigs with or without clinical AR. However, the prevalence of type D was higher on farms with pigs with AR. Types A and D with different somatic antigens could both be present in the same pig. There was no correlation between somatic types and/or capsular types with the clinical AR status of the pigs on the farm. Toxigenic isolates were found only in pigs which had a problem of clinical AR, and a great majority of these isolates belonged to type D. Since there was a high level of heterogeneity of the strains in the P. multocida population on a farm, several strains should be characterized before the diagnosis of AR could be excluded on the basis of the absence of isolation of rhinopathogenic P. multocida strains.

Osteogenesis and growth of the nasal ventral conchae of the piglet.

The present study investigated the osteogenesis and growth of the nasal ventral conchae of piglets aged from 1 to 28 days. Serial transverse sections of paraffin wax-embedded noses were stained and examined by light microscopy. Bone formation occurred in a rostrocaudal direction in the ventral scroll, dorsal scroll, connecting zone, transverse lamina and articular lamina, successively, and occurred by two ossification processes: endochondral ossification and intramembranous bone apposition. Endochondral ossification was responsible for the longitudinally, rostrally directed growth. Rapid transverse bone growth and modelling were centrifugally directed and occurred by intramembranous bone apposition at the eccentric side of the scrolls and resorption at the concentric scroll side. Elongation of the distal scroll extremities took place by intramembranous bone apposition.