Patient-reported rates of chronic pain and recurrence after groin hernia repair.

BACKGROUND: The effectiveness of different procedures in routine surgical practice for hernia repair with respect to chronic postoperative pain and reoperation rates is not clear. METHODS: This was prospective cohort study based on a unique combination of patient-reported outcomes and national registry data. Virtually all patients with a groin hernia repair in Sweden between September 2012 and April 2015 were sent a questionnaire 1 year after surgery. Persistent pain, defined as at least 'pain present, cannot be ignored, and interferes with concentration on everyday activities' in the past week was the primary outcome. Reoperation for recurrence recorded in the register was the secondary outcome. RESULTS: In total, 22 917 patients (response rate 75·5 per cent) who had an elective unilateral groin hernia repair were analysed. Persistent pain present 1 year after hernia repair was reported by 15·2 per cent of patients. The risk was least for endoscopic total extraperitoneal (TEP) repair (adjusted odds ratio (OR) 0·84, 95 per cent c.i. 0·74 to 0·96), compared with open anterior mesh repair. TEP repair had an increased risk of reoperation for recurrence (adjusted OR 2·14, 1·52 to 2·98), as did open preperitoneal mesh repair (adjusted OR 2·34, 1·42 to 3·71) at 2·5-year follow-up. No other methods of repair differed significantly from open anterior mesh repair. CONCLUSION: The risk of significant pain 1 year after groin hernia repair in routine surgical practice was 15·2 per cent. This figure was lower in patients who had surgery by an endoscopic technique, but at the price of a significantly higher risk of reoperation for recurrence.

Skatole metabolites in urine as a biological marker of pigs with enhanced hepatic metabolism.

Boar taint is a quality defect in meat, related to accumulation of skatole and androstenone in male pigs. The levels of skatole and its main metabolites in plasma and urine samples were measured with a validated liquid chromatography-MS method and related to activity of hepatic cytochrome P450 (CYP450) in order to identify 'fast metabolizing' pigs. Urine (n=46), blood (n=12), liver (n=25) and adipose tissue (n=46) were sampled from a total of 46 entire male pigs. Skatole levels in fat were negatively correlated to CYP2E1 activity and positively to 3-hydroxy-3-methyloxindole (HMOI), indole-3-carboxylic acid (ICA) and 2-aminoacetophenone in urine. HMOI and ICA levels in urine were the best predictors of high skatole levels in fat. In summary, the present study provided further evidence for the key role of CYP2E1 in skatole metabolism and suggested that measurement of HMOI and/or ICA in urine might provide information about skatole levels in live pigs.

Effects of a large northern European no-take zone on flatfish populations.

In March 2006, a 360 km² no-take zone (NTZ) was established north of Gotland in the central Baltic Sea, with the purpose to scientifically evaluate the effects of a fishing ban on flatfish populations. A monitoring programme was set up to study the populations in the NTZ and in a reference area east of Gotland where the fishing pressure was high. The programme included fishing with multimesh survey nets, modelling of potential larval export and estimation of fish consumption by large marine predators. Overall, the results showed a clear positive effect of the NTZ on turbot Scophthalmus maximus, with higher densities in the closed area compared with the fished area and also higher densities after closure compared with before. The NTZ also had older individuals and a more even sex ratio. This, in combination with a high potential for larval export from the NTZ to Gotland, shows that the marine reserve may be important for maintaining a viable S. maximus stock at Gotland. Also, for flounder Platichthys flesus, the densities were higher in the NTZ compared to the reference area and there was a net larval export to the fished area. For both species, density-dependent growth was evident, with a lower length at age in the closed area. Potential predation by grey seal Halichoerus grypus and great cormorant Phalacrocorax carbo sinesis on flatfishes, that could hamper the evaluation of the marine reserve, was also addressed. Taken together, the results show that there are clear benefits of the fishing ban for both flatfish species within the NTZ, while the net effects on fisheries are difficult to quantify.

Welfare of entire male pigs is improved by socialising piglets and keeping intact groups until slaughter.

In today's production systems, pigs raised for slaughter are mixed many times, resulting in stress and fighting. The negative consequences of mixing are probably more severe with entire males than with castrates, as they fight more. In this project, we studied a system without castration where entire male pigs met unfamiliar pigs only once. Piglets from two litters were allowed to visit each other from circa 2 weeks of age through an opening between the farrowing pens. Entire males from these litters were kept in intact groups from weaning and onwards, and they were slaughtered pen-wise in intact groups. Control pigs were raised and weaned in their litters and mixed with unknown pigs when moved to the growing-finishing unit. They were slaughtered by split marketing based on individual weight. In total, 96 entire males from 24 litters were studied. Activity and social interactions of pigs were studied by direct observations on three observation occasions per pen for pigs kept in intact groups and four occasions for control pigs. All pigs were inspected for skin lesions during raising and at slaughter. Results showed that fewer pigs in intact groups were resting (17.1% v. 28.5%; P = 0.044) and they showed less aggressive behaviour (16.1 v. 27.7 number of interactions per hour; P = 0.001) than control pigs when moved to the growing-finishing unit. They also got fewer skin lesions compared with control pigs (15 v. 35; P < 0.001). Consequently, control pigs tended to grow slower during the 1st week after mixing; however, growth rate during the whole growing-finishing phase did not differ between treatments (P = 0.205). Control pigs directed more aggressive behaviour towards non-litter mates than towards litter mates during the whole growing-finishing phase, whereas pigs from the other treatment made no difference between litter mates and other familiar pigs. At 67 kg, there was more sexual behaviour (mounting) among control pigs (7.6 v. 3.4; P = 0.033), but after slaughter no differences were found in testis weight or boar taint compounds. At slaughter, more entire males that were slaughtered pen-wise and kept in intact groups were without skin lesions compared with the mixed control pigs (74% v. 13%; P < 0.001). This study shows that the welfare of entire male pigs can be improved by socialising piglets and by keeping them in intact groups during raising and at slaughter.

Influence of slaughter age and carcass suspension on meat quality in Angus heifers.

This study investigated the effects of pelvic suspension and slaughter age on longissimus thoracis et lumborum (LTL) from 40 heifers with at least 75% Angus breeding. A total of 20 heifers were slaughtered directly from pasture at 18 months of age, and carcass sides were hung either by the Achilles tendon or the pelvic bone. The other 20 heifers were assigned to an additional winter housing period and slaughtered at 22 months of age; carcass sides were hung only by Achilles suspension. All carcasses were electrically stimulated and assessed according to the EUROP carcass classification system. In addition, the LTL muscles were aged for 7 or 14 days before meat quality was evaluated for intramuscular fat (IMF), drip loss, colour, shear force, compression and sensory analysis. The 22-month-old heifers were heavier, fatter and had more IMF than 18-month-old heifers. Conformation scores (muscling) did not differ between the two slaughter groups. Pelvic suspension reduced both between- and within-animal variation for peak force, total energy and compression peak force. For the 18-month-old heifers, pelvic suspension also decreased peak force, total energy and compression variables for the LTL muscles from both ageing periods, whereas Achilles-suspended samples had lower shear force values only at day 14. Sensory analysis showed that pelvic-suspended sides had greater tenderness, lower bite resistance, less threadiness, higher juiciness and meat flavour and less visible marbling than meat from Achilles-suspended sides. Pelvic-suspended sides at 18 months of age were similar in peak force and total energy values to the 22-month-old heifers. The importance of ageing the Achilles-suspended sides was more obvious for samples from 18-month-old heifers than from the 22-month-old animals. The correlations between the different instrumental measurements and sensory tenderness were considerably higher for carcasses suspended by the Achilles tendon (r = -0.55 to 0.20) than for those hung by the pelvic bone (r = -0.25 to 0.19). More correlations between sensory-evaluated tenderness and shear variables were significant after 7 days (n = 6) of ageing than after 14 days (n = 4) of ageing. This study clearly shows the benefits of pelvic suspension, which reduces the need for additional feeding after pasture.

Early vaccination with Improvac®: effects on performance and behaviour of male pigs.

The aim of this study was to investigate the effect of giving a two-dose regimen of gonadotropin-releasing hormone vaccine, Improvac® (Pfizer Ltd), earlier than currently recommended, on performance and behaviour of growing/finishing pigs. Cross-bred male pigs (n = 192) were randomly allocated, within a litter, into four groups at birth: one group of pigs surgically castrated without anaesthesia before one week of age, a second group of early vaccinated pigs given Improvac at 10 and 14 weeks of age, a third group of standard vaccinated pigs given Improvac at 16 and 20 weeks of age, so that the second vaccination was given 4 to 6 weeks before slaughter as recommended by the manufacturer, and a fourth group of entire male pigs. The experiment started when the pigs were 12 weeks old and lasted until 25 weeks of age, when the pigs were slaughtered. The pigs were fed restrictedly. Daily weight gain and feed conversion during the entire raising period did not differ significantly between groups. Estimated lean meat content of early vaccinated and surgically castrated pigs was lower when compared with entire male pigs, whereas standard vaccinated pigs did not differ from entire males. Dressing percentage was higher in early vaccinated and surgically castrated pigs than in standard vaccinated and entire male pigs, partly because of lower size and weight of reproductive organs. For both groups of vaccinated pigs, both problematic and non-problematic behaviours decreased after their second injection, from the levels of entire males to those of surgically castrated pigs. After the second injection, pigs of both vaccination groups performed no mountings, in contrast with entire male pigs of the same age. Skin lesions at slaughter were fewer and less severe for vaccinated pigs compared with entire male pigs. No difference in income per carcass was observed for surgically castrated or vaccinated pigs. However, for entire male pigs the income was lower, as the payment system in Sweden also takes into consideration the additional cost for boar taint analyses and reduced payment for tainted carcasses. Under our experimental conditions, early vaccination with Improvac can be used as an alternative to the recommended schedule to minimise problematic behaviour with unaffected profitability.

Electrical stimulation affects metabolic enzyme phosphorylation, protease activation, and meat tenderization in beef.

The objective of this study was to investigate the response of sarcoplasmic proteins in bovine LM to low-voltage electrical stimulation (ES; 80 V, 35 s) after dressing and its contribution to meat tenderization at an early postmortem time. Proteome analysis showed that ES resulted in decreased (P < 0.05) phosphorylation of creatine kinase M chain, fructose bisphosphate aldolase C-A, ß-enolase, and pyruvate kinase at 3 h postmortem. Zymography indicated an earlier (P < 0.05) activation of µ-calpain in ES muscles. Free lysosomal cathepsin B and L activity increased faster (P < 0.05) in ES muscles up to 24 h. Immunohistochemistry and transmission electron microscopy further indicated that lysosomal enzymes were released at an early postmortem time. Electrical stimulation also induced ultrastructural disruption of sarcomeres. In addition, ES accelerated (P < 0.05) the depletion of ATP, creatine phosphate, and glycogen, as well as a pH decline and the more preferred pH/temperature decline mode. Finally, ES accelerated meat tenderization, resulting in lesser (P < 0.05) shear force values than the control over the testing time. A possible relationship was suggested between a change in the phosphorylation of energy metabolic enzymes and the postmortem tenderization of beef. Our results suggested the possible importance of the activation of µ-calpain, phosphorylation of sarcoplasmic proteins, and release of lysosomal enzymes for ES-induced tenderization of beef muscle.

Influence of vitamins A, D3 and E status on post-mortem meat quality in steers under winter housing or pasture finishing systems.

We investigated the influence of Swedish recommended vitamins A, D3 and E supplementation levels on muscle tenderness and fatty acid (FA) composition under indoor or outdoor finishing programmes. Swedish Red breed steer calves were divided into vitamin supplemented (n = 12) and non-supplemented (n = 15) groups while on pasture prior to the finishing period. This trial began at the beginning of the winter housing period during which the steers were fed a 55 : 45 dry matter barley : grass silage diet indoors. The indoor finished group was comprised of vitamin supplemented (n = 6) and non-supplemented (n = 8) steers slaughtered after about 155 days on feed. Vitamin supplemented steers were provided with 100 g mineral supplement providing 400 000 IU vitamin A, 100 000 IU D3 and 3000 IU E daily as recommended for Swedish production practices. In spring, outdoor finished vitamin supplemented (n = 6) and non-supplemented (n = 7) steers grazed semi-natural grassland for an additional 120 days before slaughter. During pasture, vitamin supplemented steers had free-choice access to a mineral supplement containing vitamins A, D3 and E. The mineral supplement for the non-supplemented steers did not contain vitamins A, D3 and E and was provided at the same amount as the vitamin supplemented steers. Shear force values were similar between vitamin supplemented and non-supplemented steers after ageing 2, 7 and 14 days within indoor and outdoor finishing programmes. The shear force values had decreased by 14 days of ageing within all programmes. The µ- and m-calpain activity did not differ between vitamin supplemented and non-supplemented steers for either the indoor or outdoor finishing programmes. The calpastatin activity was higher for the indoor, vitamin supplemented steers. Indoor finished vitamin supplemented steers had a greater proportion of C18:1c-9 and total monounsaturated fatty acids, whereas the non-supplemented steers had a greater proportion of total saturated fatty acids. We concluded that the meat quality from steers not receiving vitamin supplementation was similar to that of steers receiving vitamins A, D3 and E supplementation at Swedish recommended levels under indoor and outdoor finishing programmes.

Immunocastration reduces aggressive and sexual behaviour in male pigs.

The aim of this study was to evaluate the effectiveness of a gonadotropin-releasing hormone (GnRH) vaccine, Improvac™ (Pfizer Ltd), in suppressing aggressive and sexual behaviour of male pigs. One hundred and thirty-six pigs were assigned to three treatments: entire male pigs (n = 64), immunocastration against GnRH (n = 48) and surgical castration (n = 24). Surgical castration was performed before the age of 1 week. Vaccination comprised two injections: the first injection was given 8 to 11 weeks before slaughter and the second injection 4 weeks before slaughter. After the second injection, immunocastrated pigs showed less non-violent social and aggressive behaviours than entire male pigs of the same age. Mounting was reduced to the same low level as observed in surgically castrated pigs, and more immunocastrated pigs were without skin lesions compared with entire male pigs. Pigs that received the second injection only 1 week before the observation day did not differ significantly in behaviour from those that received the injection 3 weeks before the observation day. Thus, the behaviour seems to change soon after the second injection and these changes remain until slaughter.

Short- and long-term effects of immunization against gonadotropin-releasing hormone, using Improvac, on sexual maturity, reproductive organs and sperm morphology in male pigs.

The objective of this study was to determine the short and long term effects of a gonadotropin-releasing hormone (GnRH) vaccine (Improvac Pfizer Ltd.), on sexual maturity, development of the reproductive organs, and the morphology of caudal epididymal spermatozoa in non-castrated male pigs. The pigs were slaughtered 4, 16 or 22 weeks after the second Improvac vaccination. A total of 80 crossbred non-castrated male pigs were included in this study comprising two experiments, a short-effect (Experiment 1) and a long-effect (Experiment 2). The first experiment included 56 pigs, 24 of them were maintained as controls and 32 were vaccinated twice, and slaughtered 4 weeks after the second vaccination. The second experiment included 24 pigs, 12 controls and 12 vaccinated twice, and slaughtered either 16 weeks (n=6) or 22 weeks (n=6) after the second vaccination. None of the immunized pigs was sexually mature at slaughter, i.e. 4, 16 or 22 weeks after second vaccination. Corresponding results of the control pigs showed that 50% had reached sexual maturity at the age corresponding to 4 weeks after the second vaccination, and 100% at slaughter 16, respectively, 22 weeks after vaccination. At 4, 16 and 22 weeks after second vaccination both testes weight and bulbourethral length were significantly reduced (p<0.001). The percentages of proximal droplets and abnormal heads were significantly lower in the control pigs than in the immunized pigs at slaughter 4 weeks after vaccination, whereas distal droplets were higher. For the other morphological parameters no significant differences were seen, but all mean values except for acrosome defects were numerically lower in the control pigs compared with the immunized pigs. For pigs slaughtered 16 or 22 weeks after vaccination, the vaccination effect was significant for percentages of proximal droplets, distal droplets, acrosome defects, acrosome abnormality and abnormal heads (p=0.017-0.001). The immunization clearly disrupted the number and morphology of the interstitial Leydig cells, lasting throughout the study period (4-22 weeks after vaccination). Spermatogenesis was also clearly affected in the immunized pigs, to various degrees, from mild disruption (spermatocyte loss, decrease of the normal number of layers of germ cells) to severe loss of germ cells including tubuli with Sertoli cells-only (complete disappearance of germ cells), also covering the entire study period. The results indicated that the effect of immunization persisted for at least 22 weeks after the second vaccination.

Influence of carcass suspension on meat quality of Charolais heifers from two sustainable feeding regimes.

This study investigated the effects of pelvic suspension on the meat quality of M. longissimus dorsi, M. semimembranosus and M. adductor from 35 heifers with at least 75% Charolais breeding. Two-thirds of the heifers were slaughtered directly from pasture at 18 months of age and one-third was finished indoors and slaughtered at 22 months. After slaughter and electrical stimulation one side of each carcass was re-suspended by either the achilles tendon or the pelvic bone. Longissimus muscles were aged 7 or 14 days and were then evaluated for drip loss, colour, shear force and sensory analysis. As compared to 18-month-old heifers, 22-month-old heifers were heavier, more muscular and fatter (P < 0.05). Intramuscular fat content increased with slaughter age (P < 0.003). Pelvic suspension reduced longissimus peak force values, total energy, pH and thawing losses (P < 0.05) in heifers slaughtered at 18 months. Semimembranosus showed the largest response to pelvic suspension with significantly lower peak force and total energy values. Finishing for 4 months did not affect longissimus shear forces. Achilles-suspended samples had lower shear force values after 14 v. 7 days of ageing. Pelvic-suspended samples aged 7 days were, however, just as tender as those aged 14 days. Sensory analysis of longissimus samples aged 14 days showed that samples from pelvic-suspended sides had higher tenderness, lower bite resistance, more meaty taste and less visible marbling compared with samples from achilles-suspended carcasses.

Practice on castration of piglets in Europe.

PIGCAS (Attitudes, practices and state of the art regarding piglet castration in Europe) is to our knowledge the first project that has focused on castration practice across European countries (European Union minus Bulgaria, Malta and Romania, plus Norway and Switzerland). About 250 million pigs are slaughtered in Europe each year. Of the 125 million male pigs, approximately 20% are left entire, less than 3% are castrated with anaesthesia and the rest is castrated without anaesthesia. The study identified large variations in castration procedures, both within and between countries. In females, castration is very rare, but is practiced without anaesthesia in special breeds/production systems in some of the southern countries.

Pig meat quality from entire males.

This paper constitutes an updated review of the production and meat quality aspects of rearing entire male pigs. Since a major obstacle in rearing entire males is the incidence of boar taint, possible methods for detection are also summarised. Safe and fast methods for detection of boar taint would be valuable in avoiding complaints from consumers. Pig meat quality is determined by many aspects, among which odour and taste are the most important attributes. Odour may be negatively affected by the presence of a pheromonal steroid, androstenone, and a fermentation product of l-tryptophan, skatole. Male pigs are surgically castrated in many countries to minimise the risk of accumulation of high levels of androstenone and skatole. Raising entire male pigs is more profitable because they have superior production characteristics and improved meat quality due to leaner carcasses and higher protein content, as compared to castrated pigs. Furthermore, surgical castration is negative from an animal welfare point of view. In most studies, no differences in sensory quality have been found between lean meat from entire male pigs with low levels of androstenone and skatole and pork from castrates and females. The question that remains is: which substances are responsible for boar taint besides androstenone and skatole and whether they need to be considered? The threshold values used for androstenone and skatole might also be too high for highly sensitive persons. Recent research shows that a human odorant receptor, ORD7D4, is involved in sensitivity to androstenone. If the ORD7D4 genotypes of consumer and expert panels are known, this might facilitate consumer studies in the future. There is still a great need for rapid on/at-line detection methods in abattoirs for identifying carcasses with unacceptable levels of boar taint compounds. Several emerging rapid technologies with a potential for boar taint detection have been investigated. They represent various measurement principles such as chemical sensor arrays (electronic noses), mass-spectrometry fingerprinting, ultra-fast gas chromatography, gas-phase spectrometry and biosensors. An industrial detection method should allow 100% correct classification of both acceptable and not-acceptable samples with regard to boar taint sorting criteria. There are, however, still too high a percentage of false negatives ranging from 5% to 20%. In addition, these methods do not yet seem to fulfil the industrial specifications with regard to cost efficiency, simplicity and analysis time. There is still no dedicated measurement technology available for on/at-line detection of boar-tainted carcasses that measures both androstenone and skatole.

The effect of a c.-8G>T polymorphism on the expression of cytochrome b5A and boar taint in pigs.

The level of cytochrome b5A (CYB5A) in pig testis is correlated with boar taint from androstenone and an AF016388:c.-8G>T polymorphism in CYB5A has been linked with low androstenone levels in the fat of pigs. In this study, we developed a polymerase chain reaction-based assay to genotype 1242 boars from eight lines for the c.-8G>T SNP. The c.-8T allele was found in all eight lines at a frequency ranging from 1.8% to 20.3% with an overall frequency of 8.6%. Significant deviations from Hardy-Weinberg equilibrium were found in the Hampshire, Landrace and Yorkshire breeds. The homozygous mutant c.-8TT occurred infrequently and was not found in some lines, but was consistently associated with low androstenone levels in fat. Both CYB5A mRNA and CYB5A protein levels were decreased in the c.-8TT genotype in a subset of Yorkshire boars, suggesting that low levels of CYB5A protein in the c.-8TT mutant were not due to inefficient translation of CYB5A mRNA. There were significant but modest marker effects on fat androstenone levels in Landrace, Yorkshire and a Large White/Duroc cross and fat skatole in Duroc and Sire Line breeds. There was no effect of CYB5A genotype on bulbourethral gland length, suggesting that this SNP will not affect reproductive traits. We conclude that the c.-8G>T SNP in the CYB5A gene has a significant but modest effect on boar taint in male pigs and could be useful in some breeds as part of a panel of SNP markers in a marker-assisted selection programme to produce low boar taint pigs.

Effect of freezing on sensory quality, shear force and water loss in beef M. longissimus dorsi.

The objective of this study was to determine how sensory quality, shear force and water loss differ between beef stored either chilled or frozen before cooking. Meat tenderness was analysed instrumentally and sensorially using both a consumer panel and a semi-trained panel. Both M. longissimus dorsi (LD) from eight young Holstein bulls were cut into eight samples, weighed, vacuum packed and aged at 4°C for 2, 7 or 14 days. After ageing, the frozen samples were kept at -20°C prior to heat treatment. Water holding capacity was recorded as purge or thawing loss and cooking loss or as combined loss. Sensory analyses were performed on samples aged 7 days. Peak force values declined with ageing time and freezing. Frozen meat aged 2 days had the same peak force values as chilled meat aged 7 days. Total energy was the same for both treatments at day 2 and 7, whereas at day 14 frozen samples showed significantly higher values than chilled samples. The sensory panel experienced the chilled meat to be more tender, juicier and having a more intense meat taste than the frozen meat, whereas the consumers could not find any significant difference in degree of liking. Water holding capacity was lower for the frozen samples. The results indicate that conclusions from studies concerning sensory quality of beef will depend on whether the meat has been kept chilled or frozen before testing.

Effect of polymorphism in the porcine cytochrome b5 ( CYB5A) gene on androstenone and skatole concentrations and sexual development in Swedish pig populations.

The present study investigated the presence of a single-nucleotide polymorphism (G > T) at base -8 upstream of ATG in 5' untranslated region of cytochrome b5 (CYB5A) gene in Swedish pig populations and evaluated the significance of this polymorphism for androstenone and skatole levels, sexual development and performance parameters in pigs. Frequencies of the T allele were 6.7% for Swedish Yorkshire × Landrace crossbred pigs (n = 245), 6.5% for Swedish Yorkshire (n = 99) and 12.8% for Landrace breed (n = 74). No deviations from Hardy-Weinberg equilibrium were observed in the investigated populations. In Swedish Yorkshire × Landrace crossbred entire male pigs (n = 193), plasma samples were analysed for skatole, androstenone, testosterone and oestrone sulphate, and fat samples were analysed for androstenone, skatole and free oestrone. Additionally, testis weight and bulbourethral gland length for crossbred pigs were recorded. Plasma androstenone levels were significantly lower in the G/T genotype at 90 kg live weight compared with the wild G/G genotype at the same live weight (P = 0.006). In heavier pigs, plasma androstenone levels did not differ between genotypes (P = 0.382). Fat androstenone levels were not affected by CYB5A genotype (P = 0.252). Skatole levels in the G/T genotype at 115 kg live weight were lower compared with those in the G/G genotype in plasma (P = 0.048) and fat (P = 0.028), although no differences were observed in lighter pigs. Testis weight, bulbourethral gland length, testosterone and oestrone sulphate levels in plasma, and oestrone levels in fat were not affected by genotype. We concluded that the presence of the T allele in the CYB5A gene resulted in lower androstenone levels in plasma, and lower skatole levels in fat and plasma; this reduction, however, was dependent on the live weight of the animals. Reproductive hormones and growth rate did not differ between the pigs of different genotypes, whereas a higher lean meat content was found in the G/T genotype in comparison with the G/G genotype. The practical application of those results in Sweden is doubtful because of lack of the effect on androstenone in fat and the low frequency of the T allele in the studied Swedish pig populations.

Effect of a gonadotropin-releasing hormone vaccine (Improvac) on steroid hormones, boar taint compounds and performance in entire male pigs.

The objective of this study, comprising two trials, was to evaluate the effect of a gonadotropin-releasing hormone (GnRH [corrected] vaccine Improvac; Pfizer Ltd) in a sample of the Swedish pig population. The pigs (n = 120) were assigned to three groups: control (entire male pigs), surgical castration and immunization against GnRH. Surgically castrated pigs did not express detectable levels of either testosterone or estrone sulphate (E1S) in plasma, or androstenone in fat and had lower skatole and indole levels in fat than entire male pigs. Immunization significantly reduced testes weight and bulbourethral gland length, plasma levels of the testicular hormones testosterone and E1S, and fat levels of androstenone, skatole and indole. Skatole levels in plasma were significantly lower than in entire male pigs in the second trial, but not in the first due to overall low skatole levels. All immunized pigs and surgically castrated pigs expressed skatole concentrations in fat below the level of 0.2 microg/g, above which meat is regarded as tainted. In contrast, eight entire male pigs exceeded this level. Indole levels in plasma from immunized pigs were lower than those from entire male pigs. Surgical castration caused lower daily weight gain in the suckling period compared with piglets raised intact, whereas in the post-weaning period no difference was observed. Immunization resulted in higher feed intake and daily weight gain after the second injection. The estimated lean meat content was improved in comparison with the castrated pigs, but was lower than for entire male pigs. Dressing percentage was lower in immunized pigs than in surgically castrated and entire male pigs. The frequency of skin damage did not differ between immunized and entire male pigs or between immunized and surgically castrated pigs.

Review on Medusa:a polymer-based sustained release technology for protein and peptide drugs.

The polymer-based Medusa system (Flamel Technologies) has been designed for slow release of therapeutic proteins and peptides. The Medusa II consists of a poly L-glutamate backbone grafted with hydrophobic alpha-tocopherol molecules, creating a colloidal suspension of nanoparticles (10 - 50 nm) in water. The sustained drug release is based on reversible drug interactions with hydrophobic nanodomains within the nanoparticles. In vivo, it is suggested that the therapeutic protein is displaced by endogenous proteins present in physiological fluids, leading to a slow drug release. The peak concentration is dramatically decreased and the protein release substantially extended. The Medusa technology has been applied to subcutaneous injection for several therapeutic proteins, such as IL-2 and IFN-alpha(2b), in animal models (rats, dogs, monkeys) and clinical trials in renal cancer (IL-2) and hepatitis C (IFN-alpha(2b)) patients.

Gene expression of 3beta-hydroxysteroid dehydrogenase and 17beta-hydroxysteroid dehydrogenase in relation to androstenone, testosterone, and estrone sulphate in gonadally intact male and castrated pigs.

Androstenone is one of the main compounds responsible for boar taint, and 3beta-hydroxysteroid dehydrogenase (3betaHSD) might be involved in its metabolism. In this study, the gene expression of 3betaHSD and 17beta-hydroxysteroid dehydrogenase (17betaHSD) were determined by real-time PCR analysis and related to the concentrations of androstenone, testosterone, and estrone sulphate (E1S). The experiments were performed on gonadally intact male pigs classified based on high or low fat androstenone concentrations, as predetermined by HPLC, as well as on immunocastrated and surgically castrated male pigs. The male pigs with high androstenone concentrations in fat had low 3betaHSD gene expression in liver and testis. Moreover, the 17betaHSD gene expression in liver, but not in testis, varied negatively with fat androstenone concentrations. Immunocastrated and surgically castrated male pigs had nondetectable concentrations of fat androstenone and plasma testosterone and E1S, and the castration procedure induced a significant increase of 3betaHSD and 17betaHSD gene expression. The mRNA expression was generally much greater from the 3betaHSD than from the 17betaHSD gene. Furthermore, fat androstenone was negatively correlated with liver 3betaHSD gene expression (Pearson correlation, r = -0.69; P < 0.05), and the 17betaHSD gene expression in liver was negatively correlated with plasma E1S (r = -0.95; P < 0.001), indicating an important role of liver 17betaHSD in the estrogen metabolism of gonadally intact male pigs. Another strong correlation was found between 3betaHSD and 17betaHSD gene expression in liver of the gonadally intact male pigs (r = 0.86; P < 0.01), possibly reflecting similar regulation mechanisms of these genes.