Interactive Rooting Towers and Behavioural Observations as Strategies to Reduce Tail Biting on Conventional Pig Fattening Farms.

Eight pens (25 pigs/pen; n = 200) provided with an interactive straw-filled rooting tower (experimental group) and five pens (25 pigs/pen; n = 125) with a stationary (fixed) tower without straw (control group) were compared within three fattening periods on a conventional farm with fully slatted flooring. The effectiveness of the tower to trigger favourable behaviour in feeding and outside feeding periods was assessed. The incidence of deep tail injuries was lower in the experimental group (experimental group: Odds Ratio 0.3, p < 0.001) and was influenced by the batch (Odds Ratio: 2.38, p < 0.001) but not by pen and sex. In spring, most pens were excluded due to severe tail biting. Tail injury scores were more severe in the control group in weeks 5, 6 and 7 compared to the experimental group (p = 0.002, p < 0.001, p < 0.001, respectively). Tower manipulation was more frequent during feeding compared to outside feeding time (p = 0.002). More head than tail manipulation occurred in the experimental group (p = 0.03). The interactive tower as the only measure was not appropriate to reduce tail biting sufficiently in pigs with intact tails on a conventional fattening farm. Of high priority to prevent tail biting outbreaks was the early detection of biting pigs.

Is There a Link between Suckling and Manipulation Behavior during Rearing in Pigs?

Inadequate possibilities to perform oral manipulation behavior for pigs can lead to misdirection and thus tail biting. Our study aimed to analyze manipulation behaviors of weaner pigs with focus on tail biting and the relationship with agonistic characteristics of the piglets during suckling. We analyzed the individual manipulation behavior of 188 weaner pigs. General health condition and tail lesions were determined weekly. Correlations were estimated between weight at weaning and at the end of rearing period, frequency of manipulative rearing behaviors and Dominance and social tension index based on suckling behavior. Principal component and cluster analyses were performed to identify groups of piglets which showed similar suckling and rearing behaviors. Tail biting increased at the middle and end of rearing with switching roles of biters and victims. Tail lesions were correlated with received tail biting behavior but occurred with a delay of more than a week. The frequency of performed tail biting was correlated with dominance index (rs = -0.256, p < 0.01) and weaning weight (rs = -0.199, p < 0.05). We assume that performed tail biting is more often observed in pigs who show mainly submissive behavior in teat disputes.

[Pain and distress response of suckling piglets to injection and castration under local anaesthesia with procaine and licocaine - Part 2: Defence behaviour, catecholamines, coordination of movements]. / Schmerz- und Stressbestimmung bei der Injektion und Kastration von Saugferkeln unter Lokalanästhesie mit Procain und Lidocain.

OBJECTIVE: Comparison of the effectiveness of local anaesthesia (LA) in piglet castration with the combination of scrotal and inguinal application of procaine 2 % and lidocaine 5 % to the intratesticular application of lidocaine 1 % using following parameters: adrenaline (A), noradrenaline (NA), defensive movements and coordinated movement patterns. MATERIAL AND METHODS: In 2 substudies 232 male suckling piglets (3-6 days of age) were randomly allocated to study groups. In groups L5 and group P2 lidocaine 5 % and procaine 2 % was applied inguinally and scrotally, respectively, while piglets of groups H (handling) and K (castration without local anaesthesia) were only fixated as for an injection. In group L1 lidocaine 1 % was injected intratesticularly. After 30 min piglets were were castrated, whereas animals of group H were again only fixated. In substudy 1 (n = 112) blood samples were taken to determine the concentration of catecholamines after castration. During injection and castration defensive movements were judged. In substudy 2 (n = 120) piglets completed a chute to document the individual stress level. RESULTS: Groups H and L1 demonstrated significantly less defensive movements during fixation for injection/injection compared to the other study groups (p ≤ 0.05). After the injection piglets of group P2 had significantly more difficulties in the chute and needed > 50 % more time to complete the course. In all study groups defensive movements during castration were the highest at the moment of severing the spermal cord. Group K obtained the highest possible rating of 8 and differed significantly from the other groups as well as when cutting the skin (p ≤ 0.05). Both the concentration of A and NA significantly rose in all groups. The increase in A and NA was significantly higher in group 2, as well as the increase in NA in group K, both in comparison to the other study groups (p ≤ 0.05). CONCLUSION: None of the applied techniques for local anaesthesia achieved a complete elimination of pain during castration of suckling piglets. The behaviour analysis indicated an altogether higher distress for P2. After castration, this injection led to a neuroendocrine pain reaction that was comparable to or higher than that of group K. In both lidocaine groups (L1, L5) the pain reaction after castration tended to be lower. These results provide approaches to apply longer acting LA with a higher analgesic potency in an appropriate dosage and with an appropriate method of application.

[Pain and distress responses of suckling piglets to injection and castration under local anaesthesia with procaine and lidocaine - Part 1: Cortisol, chromogranin A, wound healing, weights, losses]. / Schmerz- und Stressbestimmung bei der Injektion und Kastration von Saugferkeln unter Lokalanästhesie mit Procain und Lidocain.

OBJECTIVE: Comparison of the effectiveness of local anaesthesia (LA) in piglet castration by procaine 2 % and lidocaine 5 % both through combined inguinal and scrotal application as well as by intratesticular application of lidocaine 1 %. The parameters used were serum cortisol and chromogranin A (CgA) concentrations as well as wound healing, body weight and animal losses. MATERIAL AND METHODS: In 2 substudies, a total of 232 male piglets aged 3-6 days were included. Substudy 1 (112 piglets): Group H: fixation of piglets as for an injection; group L5: inguinal and scrotal injection of lidocaine 5 %; group P2: inguinal and scrotal injection of procaine 2 %; group L1: intratesticular injection of lidocaine 1 %. In all the groups, blood samples were taken 45 minutes before and 30 minutes post-injection (p. i.). Substudy 2 (120 piglets): Group H: handling only as for an injection and castration; group K: handling as for an injection and castration without LA after 30 minutes. Groups L5, P2 and L1: management as in substudy 1 and castration after 30 minutes. Blood samples were taken 75 minutes before as well as 30, 60 and 240 minutes post-castration (p. c.). The evaluated parameters were serum cortisol and CgA concentrations, wound healing, body weight and piglet losses. RESULTS: Substudy 1: The elevation of the cortisol and CgA concentrations in group P2 p. i. were significantly higher than in the other groups. The mean total cortisol concentration of group P2 p. i. was significantly higher than those of the other groups. Substudy 2: At 30 minutes p. c., all the groups displayed a significant increase in the cortisol concentration compared to group H. In group P2, the highest total cortisol concentration was measured 60 minutes p. c. and the elevation of the cortisol level was significantly higher than in the other groups. In group L1, a significantly greater increase in the CgA level was observed at 60 minutes p. c. when compared to the other groups. Regarding wound healing, body weight and losses, there were no significant differences between the groups. CONCLUSION: The combined inguinal and scrotal injection of procaine 2 % induced a greater neuroendocrine stress response than the inguinal and scrotal injection of lidocaine 5 % and the intratesticular injection of lidocaine 1 %. LA using procaine 2 %, lidocaine 5 % or lidocaine 1 % did not completely eliminate pain during castration. Castration under LA with procaine 2 % induced a greater pain reaction than castration without LA. Both groups castrated with LA using lidocaine (L1, L5) tended to display lower pain responses after castration than group K. On the basis of the findings of this study, other local anaesthetics that have a stronger effect could be further investigated according to their pain-killing effects in an appropriate application route.

Modified ventilatory response characteristics to exercise in breath-hold divers.

Specific adjustments to repeated extreme apnea are not fully known and understood. While a blunted ventilatory chemosensitivity to CO2 is described for elite breath-hold divers (BHDs) at rest, it is unclear whether specific adaptations affect their response to dynamic exercise. Eight elite BHDs with a previously validated decrease in CO2 chemosensitivity, 8 scuba divers (SCDs), and 8 matched control subjects were included in a study where markers of ventilatory response, Fowler's dead space, partial pressure of carbon dioxide (pCO2), and blood lactate concentrations during cycle exercise were measured. Maximal power output did not differ between the groups, but lactate threshold (θL) appeared at a significantly lowered respiratory compensation point (RCP) and at a higher VO2 for the BHDs. End-tidal (petCO2) and estimated arterial pCO2 (paCO2) were significantly higher in BHDs at θL, the RCP, and maximum exhaustion. BHDs showed a significantly (P < .01) slower breathing pattern in relation to a given tidal volume at a specific work rate. In summary, BHDs presented signs of a metabolic shift from aerobic to anaerobic energy supply, decreased chemosensitivity during exercise, and a distinct ventilatory-response pattern during cycle exercise that differs from SCDs and controls.

Breath-hold diving: respiratory function on the longer term.

PURPOSE: Extensive breath-hold (BH) diving imposes high pulmonary stress by performing voluntary lung hyperinflation maneuvers (glossopharyngeal insufflation, GI), hyperinflating the lung up to 50% of total lung capacity. Breath-hold durations of up to 10 min without oxygen support may also presume cerebral alterations of respiratory drive. Little is known about the long-term effects of GI onto the pulmonary parenchyma and respiratory adaptation processes in this popular extreme sport. METHODS: Lung function assessments and subsequent measures of pulmonary static compliance were obtained for 5 min after GI in 12 elite competitive breath-hold divers (BHD) with a mean apnea diving performance of 6.6 yr. Three-year follow-up measurements were performed in 4 BHD. Respiratory drive was assessed in steady-state measurements for 6% and 9% CO2 in ambient air. RESULTS: Short-term pulmonary stress effects for static compliance during GI (13.75 L·kPa) could be confirmed in these 12 divers without exhibiting permanent changes to the lungs' distensibility (7.41 L·kPa) or lung function parameters as confirmed by the follow-up measurements and for 4 BHD after 3 yr (P>0.05). Respiratory drive was significantly reduced in these BHD revealing a characteristic breathing pattern with a significant increase in VE and mouth occlusion pressure (P0.1) between free breathing and 6% CO2, as well as between 6% CO2 and 9% CO2 (all P<0.001). CONCLUSION: BH diving with performance of GI does not permanently alter pulmonary distensibility or impair ventilatory flows and volumes. A blunted response to elevated CO2 concentrations could be demonstrated, which was supportive of the hypothesis that CO2 tolerance is a training effect due to BH diving rather than being an inherited phenomenon.

Glossopharyngeal insufflation and pulmonary hemodynamics in elite breath hold divers.

PURPOSE: Acute voluntary lung hyperinflation provoked by glossopharyngeal insufflation (GI) elicits numerous, possibly deleterious, effects on the cardiopulmonary system by increasing intrathoracic pressures far above normal values. This study quantifies acute pulmonary hemodynamics during GI using phase-contrast magnetic resonance imaging (MRI). METHODS: Hemodynamic parameters were measured in nine elite male breath hold divers with a mean age of 30 yr (range = 20-43 yr) by velocity-encoding cine (VEC)-MRI of the main pulmonary artery (PA) before, during, and after GI. Simultaneously, GI-lung volume (GIVEC-MRI) was measured by MR-compatible spirometry. RESULTS: Hemodynamic parameters were associated with GIVEC-MRI. Highly significant changes during GI were shown for the mean flow in the PA, which decreased by 45% (P < 0.007), and right ventricular output and cardiac index, which decreased by 41% and 40%, respectively (P < 0.007). Acceleration time also decreased highly significant by 36% during GI (P < 0.007). All hemodynamic parameters except acceleration time returned to baseline after GI. CONCLUSIONS: Acute voluntary lung hyperinflation mimics changes seen in pulmonary arterial hypertension, but unlike the latter, these changes are fully reversible shortly after cessation of voluntary lung hyperinflation. Persistent changes due to repetitive GI could not be detected.

Characteristics of the respiratory mechanical and muscle function of competitive breath-hold divers.

Competitive breath-hold divers (BHD) employ glossopharyngeal insufflation (GI) to increase intrapulmonary oxygen stores and prevent the lungs from dangerous compressions at great depths. Glossopharyngeal insufflation is associated with inflation of the lungs beyond total lung capacity (TLC). It is currently unknown whether GI transiently over-distends the lungs or adversely affects lung elastic properties in the long-term. Resting lung function, ventilatory drive, muscle strength, and lung compliance were measured in eight BHD who performed GI since 5.5 (range 2-6) years on average, eight scuba divers, and eight control subjects. In five BHD subsequent measures of static lung compliance (Cstat) were obtained after 1 and 3 min following GI. Breath-hold divers had higher than predicted ventilatory flows and volumes and did not differ from control groups with regard to gas transfer, inspiratory muscle strength, and lung compliance. A blunted response to CO2 was obtained in BHD as compared to control groups. Upon GI there was an increase in mean vital capacity (VCGI) by 1.75 +/- 0.85 (SD) L compared to baseline (p < 0.001). In five BHD Cstat raised from 3.7 (range 2.9-6.8) L/kPa at baseline to 8.1 (range 3.4-21.2) L/kPa after maximal GI and thereafter gradually decreased to 5.6 (range 3.3-8.1) L/kPa after 1 min and 4.2 (range 2.7-6.6) L/kPa after 3 min (p < 0.01). We conclude that in experienced BHD there is a transient alteration in lung elastic recoil. Resting lung function did not reveal a pattern indicative of altered lung ventilatory or muscle function.