Heritability of the backtest response in piglets and its genetic correlations with production traits.

The backtest response of a pig gives an indication of its coping style, that is, its preferred strategy to cope with stressful situations, which may in turn be related to production traits. The objective of this study was therefore to estimate the heritability of the backtest response and estimate genetic correlations with production traits (birth weight, growth, fat depth and loin depth). The backtest was performed by placing the piglet on its back for 60 s and the number of struggles (NrS) and vocalizations (NrV), and the latency to struggle and vocalize (LV) was recorded. In total, 992 piglets were subjected to the backtest. Heritability estimates for backtest traits were statistically moderate (although high for behavioral traits), with LV having the highest heritability estimate (0.56±0.10, P<0.001) and NrS having the lowest estimate (0.37±0.09, P<0.001). Backtest traits also had high genetic correlations with each other, with vocalization traits (NrV and LV) having the highest (-0.94±0.03, P<0.001), and NrS with NrV the lowest correlation (0.70±0.09, P<0.001). No significant correlations were found between backtest traits and production traits, but correlations between NrS and birth weight (-0.38±0.25), and NrV and loin depth (-0.28±0.19) approached significance (P=0.07). More research into genotype-by-environment interactions may be needed to assess possible connections between backtest traits and production traits, as this may depend on the circumstances (environment, experiences, etc.). In conclusion, heritability estimates of backtest traits are high and it would therefore be possible to select for them. The high genetic correlations between backtest traits indicate that it may be possible to only consider one or two traits for characterization and selection purposes. There were no significant genetic correlations found between backtest traits and production traits, although some of the correlations approached significance and hence warrant further research.

Damaging biting behaviors in intensively kept rearing gilts: the effect of jute sacks and relations with production characteristics.

Pigs may display biting behavior directed at pen mates, resulting in body damage such as tail wounds. We assessed the suitability of jute sacks (hung vertically at wall) to reduce biting behaviors and tail wounds in rearing gilts. Additionally, we assessed several characteristics of different types of tail biters. Tail docked rearing gilts originated from 72 litters, which were kept in partly slatted pens with jute sacks (J) or barren control pens (CON; 36 litters per treatment). Tail and ear damage were observed at weaning (4 wk) and during the weaner and rearing phase (17 J and 19 CON pens). Sow (dam) damage was also considered. Biting behaviors (tail, ear, and other) were observed during the weaner and rearing phase. Weight was recorded at birth, weaning, and end of the weaner phase and ADG was calculated from birth till weaning and from weaning till 9 wk. Furthermore, estimated breeding values for litter size, litter birth weight, back fat, and growth between birth and ∼ 105 kg, and ∼ 25 to 105 kg were determined. Jute sacks reduced tail and ear damage at weaning (both P < 0.001) and tended to reduce sow tail damage (P = 0.09). Jute sacks also reduced tail damage post-weaning (P < 0.001 to 0.03), with a 5-fold reduction of (mild) tail wounds at the age of 13 wk. Biting behaviors directed at pen mates were up to 50% lower in J pens (P < 0.001 to 0.04). Higher genotypic litter size, litter birth weight, growth, and lower back fat seemed associated with higher levels of ear or tail-biting behavior (P = 0.002 to 0.09), albeit dependent on treatment and phase. Higher phenotypic litter sizes were associated with higher levels of biting behaviors (P = 0.004-0.08). High-tail-biters and Medium-tail-biters (the latter less pronounced) stemmed from larger litters (P = 0.01 to 0.05), were heavier (P = 0.03 to 0.04), grew faster (P = 0.05 to 0.08), and displayed higher levels of all kinds of biting behavior directed to pen mates and the jute sack (P < 0.001 to 0.10) compared with non-tail-biters, the effect size dependent on treatment and phase of life. To conclude, jute sacks may profoundly reduce damaging behaviors and tail wounds in rearing gilts, probably because they partly meet the behavioral need of pigs for rooting and chewing. Furthermore, (tail) biting is associated with production level of the gilts (phenotypically and genetically), which suggests a role for breeding programs and additional research focusing on metabolic demands of (tail) biting pigs.

Struggling to survive: early life challenges in relation to the backtest in pigs.

Intensively reared piglets may face many early life challenges and these may affect behavior. The objective of this study was to examine the relationship between piglets' early life circumstances and their behavioral response in a backtest. Here, 992 piglets of 14 d of age were subjected to a backtest, in which they were restrained for 1 min in a supine position. The number of struggles in the backtest was assessed in relation to data on ADG, BW, BW relative to litter mates, teat order, litter size, and health. Piglets that had a lower ADG from birth until the test day were struggling more (b = -2.4 g ADG/struggle; P = 0.03). Also, piglets with a lower BW at 14 d of age tended to respond more actively in the backtest (b = -0.03 kg/struggle; P = 0.08). The response to the backtest was unrelated to ADG from birth until weaning, birth weight, weaning weight, teat order, litter size, and health. ADG and BW were unrelated to the variation of backtest responses within the litter. The weak though significant relationship suggests that smaller, slower-growing piglets more actively respond to a challenge, either because piglets born with such a behavioral response were better able to survive, or because piglets adapted their behavioral response to their physical condition.

Backtest and novelty behavior of female and castrated male piglets, with diverging social breeding values for growth.

Pigs housed together in a group influence each other's growth. Part of this effect is genetic and can be represented in a social breeding value. It is unknown, however, which traits are associated with social breeding values. The aim of this study was, therefore, to investigate whether personality and response to novelty could be associated with social breeding values for growth in piglets. Female and castrated male piglets from 80 litters, with either an estimated relative positive or negative social breeding value (+SBV or -SBV) for growth, were individually tested in a backtest and novel environment test, and group-wise in a novel object (i.e., a feeder with feed) test and human approach test. All tests were performed during the suckling period. No differences between +SBV and -SBV piglets were found for the frequency and latency of struggling and vocalizing in the backtest (at least, P > 0.30). In the novel object test, piglets with a +SBV for growth touched the feeder faster than piglets with -SBV for growth (P = 0.01) and were more frequently present near the person in the human approach test (P < 0.01). No behavioral differences between +SBV and -SBV piglets were found in the novel environment test (at least, P > 0.40), but piglets that struggled more in the backtest walked more in this test (P = 0.02). Behavior was affected by gender in each test. Female piglets were faster than castrated male piglets to start struggling in the backtest (P = 0.047). In the novel object test, females were faster than males to touch the feeder and sample the feed. In the human approach test, they were also faster than male piglets to touch a person (all, P < 0.001). Females were also more frequently present near the feeder (P < 0.001) and person (P = 0.03). In the novel environment test, female piglets explored the floor more (P = 0.046), produced less low- (P = 0.04) and high-pitched vocalizations (P = 0.02), and defecated (P = 0.08) and urinated less than male piglets (P < 0.01). It was concluded that +SBV and -SBV piglets do not differ in their response to the backtest, and only subtle differences were found in their response to novelty. More research is warranted to identify the traits underlying SBV for growth in pigs. Moreover, castrated male piglets seemed to react more fearfully to each test than female piglets.

[Experimental animal studies on the problem of sealing a woven vascular prosthesis and a textile patch by direct-current activated autologous blood]. / Tierexperimentelle Untersuchungen zur Frage der Abdichtung einer gewebten Gefässprothese und eines textilen Patch mittels Gleichstrom aktivierten autologen Blutes.

The results of our animal experiments showed that the sealing of a woven vascular prosthesis or a textile patch by in vitro electrically activated blood by means of direct current is an alternative for the sealing by fibrin adhesive. The materials sealed in this way are resistant to the endogenic fibrinolysis. This simple and non-expensive method is not useful for heparinised blood and in disturbances of coagulation.

[Animal experimental and clinical studies on the behavior of an in vitro electrically produced thrombus mass]. / Tierexperimentelle und klinische Untersuchungen über das Verhalten der in vitro elektrisch gewonnenen Thrombusmasse.

In the electric field the solid blood components will move to the anode because of their negative surface charge. When influenced by a direct current of constant force and duration a thrombus differing in size will develop depending on the composition of the coagulation system. This regularity could be used for diagnostic purposes. By means of experiments with animals and clinical examinations the development of the "electro-clot" is observed in vitro before and after the administration of heparin. In addition, the behaviour of the thrombus developed in vitro in the electric field is checked in patients affected with obstructive lung diseases. Here a correlation existing between the mass of the thrombus and hematocrit could be proved.

[Patent ductus arteriosus in premature infants with respiratory distress syndrome]. / Problematik des Ductus arteriosus apertus bei Frühgeborenen mit Atemnotsyndrom.

Since April 1983 10 premature infants suffering from patent ductus arteriosus combined with respiratory distress syndrome have been seen at our dept. for being treated surgically. One infant came to death due to bronchopulmonary dysplasia. The first 6 cases of this series were dealt with in detail. The possibility of conservative treatment (Indomethazin) or ligature of the duct are discussed.

[Experimental studies on the problem of improving the myocardial blood circulation in an intraoperatively resuscitated heart]. / Experimentelle Untersuchungen zur Frage der Verbesserung der Herzmuskeldurchblutung eines intraoperativ reanimierten Herzens.

A pumping system for supporting an intraoperatively failured heart is presented. This system consists of a bell-shaped receptacle for the heart and a pump with a working volume of 49 ml and a working pressure of 220 Torr. The pumping power is transmitted to the heart by means of an external pneumatic pressure line. The efficacy of the pump in the high pressure system amounted to 20-30 per cent. An effective coronary perfusion in case of a cardiac failure is guaranteed by a venous underpressure pump of this pumping system. A favourable influence was also observed in case of the low pressure system.

The sealing of vascular prostheses using autologous electrically activated blood.

Due to preclotting of the vascular prosthesis, autologous blood has shown good results provided that heparinization has not become necessary, or blood coagulation disorders are not present. In cases where replacement of the aorta is performed in the thoracic cavity with extracorporeal circulation or in the case of severe coagulopathies, preclotting with autologous blood does not show satisfactory results. In this presentation we report on a new method of sealing vascular prostheses with the help of autologous blood activated electrically "in vitro". The direct current changes the blood in vitro into a thrombogenic substance. Sealing is effected by placing the outer wall of the prosthesis in electrically activated blood.

[Mitral commissurotomy or mitral valve replacement. Comparison of results of closed and open operative procedures in acquired mitral valve stenoses and combined mitral valve defects, predominantly stenosis]. / Mitralkommissurotomie oder Mitralklappenersatz. Vergleich der Ergebnisse geschlossener und offener Operationsverfahren bei erworbenen Mitralstenosen und kombinierten Mitralklappenfehlern mit vorwiegender Stenose.

1012 closed operations for mitral stenoses, mitral restenoses and combined mitral and aortic stenoses were performed from 1963 to 1981. Moreover 888 operations were performed at the mitral valve from 1973 to October 1983 as open heart procedures: 676 cases of mitral valve replacement (MVR) including 7 cases of coronary artery operations; 4 cases both of mitral, aortic and tricuspidal valve replacement or mitral and tricuspidal valve replacement; 9 cases of valve reinsertion; 20 cases of open commissurotomy and 4 cases of annular plastic according to Wooler. The functional results after open operation are quite better than those after closed procedures. The rate of reoperations after MVR is only 3% but after closed operations more than 25%. In this way we believe the open operation to be the better way of treating acquired mitral stenosis. In our opinion the closed method may be used in cases of late pregnancy and in those centres having an insufficient capacity for open heart surgery to be performed.

[Dynamics of the heart rate in active orthostasis of patients with hemodynamically effective mitral valve stenosis]. / Die Dynamik der Herzfrequenz bei der aktiven Orthostase von Patienten mit hämodynamisch wirksamer Mitralklappenstenose.

Heart rate dynamics in response to active orthostasis of 10 min duration were examined in 48 patients with mitral stenosis and compared with the mean and diastolic pulmonary artery pressure. Classification of the characteristics of the heart rate was done according Drischel and co-workers (1963) using amplitude and time values. In contrast to healthy subjects, in patients with mitral stenosis the best regulatory behavior was observed in type B with lower pulmonary artery pressure, the least favorable regulatory dynamics being predominant in type A with higher pulmonary artery pressure. From a functional diagnostic point of view, regulatory efficiency can be graded on the following descending scale: (1) the best regulatory behavior in type B; (2) a decrease in the amplitude values in type B; (3) transition of the dynamics to type A; and (4) prolongation of the time values in type A. The pathophysiological mechanisms are changes in the sensitivity of dilatation receptors in the intrathoracic low-pressure system and of the carotid baroreceptors.

[Sound spectrographic studies in the diagnosis of dysfunctions of mechanical heart valve prostheses (Björk-Shiley prostheses)]. / Schallspektrographische Untersuchungen zur Diagnose von Dysfunktionen mechanischer Herzklappenprothesen (Björk-Shiley-Prothesen).

A newly developed real-time sound spectroanalyzer was found to be capable of diagnosing malfunction of prosthetic heart valves (Björk-Shiley prostheses). Sound spectroanalysis was carried out 430 times on 257 patients with a prosthetic heart valve. The valvular click of prosthetic heart valves shows a typical sound spectroanalysis pattern in real time, with a high-frequency peak which diminishes beyond 25 kHz. Thrombosis of the prosthetic heart valve causes loss of the valvular click and reduction in the intensity of the high-frequency components, as shown in 4 patients. Thus the sound spectroanalysis appears to be a noninvasive technique which may allow early diagnosis of a thrombosed prosthetic heart valve. We believe this method to be superior to phonocardiography and echocardiography.

[Surgical treatment of the scimitar syndrome]. / Die operative Behandlung des Scimitarsyndroms.

Anomalous pulmonary venous drainage of the right lung into the inferior vena cava is an uncommon congenital defect. In 440 patients suffering from atrial septal defect (with or without anomalous pulmonary venous drainage) we could demonstrate the Scimitar-Syndrome in five cases. The described side-to-side-anastomosis between the anomalous vein and the left or right atrium is an alternative procedure to well-known operative methods.

[Aneurysm of the membranous septum of the heart. A diagnostic and therapeutic challenge]. / Aneurysmen des Septum membranaceum des Herzens. Eine diagnostische und therapeutische Aufforderung.

Aneurysms of the membranous portion of the interventricular septum are considered to be rare cardiac lesions. Left ventricular angiography appears to be the only method to establish the specific intravital diagnosis. Rupture, infection, thromboembolism, and obstruction of the right ventricular outflow tract have been documented for complications of this malformation. Early resection should be performed before complications occur. 4 patients underwent successful open heart correction of the aneurysm. In another patient a bundle branch block was present and a pacemaker was implanted.