Marina Štukelj

The effect of the combination of acids and tannin in diet on the performance and selected biochemical, haematological and antioxidant enzyme parameters in grower pigs.

BackgroundThe abolition of in-feed antibiotics or chemotherapeutics as growth promoters have stimulated the swine industry to look for alternatives such as organic acids, botanicals, probiotics and tannin. The objective of the present study was to compare the effects of a combination of acids and tannin with diet with organic acids and diet without growth promoters on the growth performance and selected biochemical, haematological and antioxidant enzyme parameters in grower pigs. Tannin is more natural and cheaper but possibly with the same effectiveness as organic acids with regard to growth performance.MethodsThirty-six 7 week old grower pigs, divided into three equal groups, were used in a three week feeding trial. Group I was fed basal diet, group II basal diet with added organic acids and group III basal diet with added organic and inorganic acids and tannin. Pigs were weighed before and after feeding and observed daily. Blood was collected before and after the feeding trial for the determination of selected biochemical, haematological and antioxidant enzyme parameters. One-way ANOVA was used to assess any diet related changes of all the parameters. Paired t-test was used to evaluate changes of blood parameters individually in each group of growers before and after feeding.ResultsNo clinical health problems related to diet were noted during the three week feeding trial. The average daily gain (ADG) and selected blood parameters were not affected by the addition to basal diet of either acids and tannin or of organic acids alone. Selected blood parameters remained within the reference range before and after the feeding trial, with the exception of total serum proteins that were below the lower value of reference range at both times. The significant changes (paired t-test) observed in individual groups before and after the feeding trial are related to the growth of pigs.ConclusionDiet with acids and tannin did not improve the growth performance of grower pigs but had no deleterious effects on selected blood parameters. The possibility of beneficial effects of adding acids and tannin in diets on growth performance over a longer period, however, could not be excluded.

Relevant Measures to Prevent the Spread of African Swine Fever in the European Union Domestic Pig Sector

During the past decade, African swine fever (ASF) has spread from the Caucasus region to eastern European Union countries affecting domestic pig and wild boar populations. In order to avert ASF spread, mitigation measures targeting both populations have been established. However, despite these efforts, ASF has been reported in thirteen different countries (Georgia, Azerbaijan, Armenia, the Russian Federation, Ukraine, Belarus, Estonia, Latvia, Lithuania, Poland, Moldova, Czech Republic, and Romania). In the absence of an effective vaccine or treatment to ASF, introduction and spread of ASF onto domestic pig farms can only be prevented by strict compliance to control measures. This study systematically reviewed available measures to prevent the spread of ASF in the EU domestic pig sector distinguishing between commercial, non-commercial, and outdoor farms. The search was performed in PubMed and using a common browser. A total of 52 documents were selected for the final review process, which included scientific articles, reports, EU documents and official recommendations, among others. From this literature review, 37 measures were identified as preventive measures for the introduction and spread of ASF. Subsequently, these measures were assessed by ASF experts for their relevance in the mitigation of ASF spread on the three mentioned types of farms. All experts agreed that some of the important preventive measures for all three types of farms were: the identification of animals and farm records; strict enforcement of the ban on swill feeding; and containment of pigs, so as to not allow direct or indirect pig–pig and/or pig–wild boar contacts. Other important preventive measures for all farms were education of farmers, workers, and operators; no contact between farmers and farm staff and external pigs; appropriate removal of carcasses, slaughter residues, and food waste; proper disposal of manure and dead animals, and abstaining from hunting activities during the previous 48 h (allowing a 48 h interval between hunting and being in contact with domestic pigs). Finally, all experts identified that the important preventive measures for non-commercial and outdoor farms is to improve access of those farms to veterinarians and health services.

A Review of African Swine Fever – Disease that is Now a Big Concern in Europe

Summary African swine fever (ASF) is a serious disease of domestic and feral swine mainly because of grave clinical course of the disease and its strong socio-economic impact. Not only there is an extremely high mortality (95–100%) around the time of the first outbreak, live-animal, pork meat and other pork product trade is strongly affected on regional and international level. ASF is a species-specific disease; strength of the clinical signs depends on virulence of a viral strain. Exacerbation of body temperature and dysfunction of respiratory system and gastrointestinal tract are most common occurrences. Lesions can be mostly classed as congestive or hemorrhagic. Epidemiologically, ASF varies substantially among regions, countries and continents due to wide panel of different virus genotypes, population of feral swine and other reservoirs of disease, geographical characteristics and social habits of people. ASF is endemic in Sub-Saharan Africa where soft ticks (Argaside) and chronically infected feral swine population serve as reservoirs. It also became endemic in most parts of Russian Federation. Since 1978, ASF is endemic on Sardinia isle, as it was eradicated in all other parts of Europe. First outbreak in Georgia in 2007 has apparently served for transmission to other eastern European countries. Slovenia is currently still ASF-free but disease has already reached some relatively nearby countries (Poland, Romania, Moldova, Czech Republic and Hungary). There is no anti-ASF vaccine currently available ad specific treatment has not been described. Therefore rapid diagnostics and implementation of strict biosecurity measures play a key role in prevention of further transmission.

Variations in the detection of anti-PEDV antibodies in serum samples using three diagnostic tests – short communication

Over the last few years several porcine epidemic diarrhoea (PED) outbreaks have been discovered in Europe including the first PED case in Slovenia in January 2015. The aim of this study was to determine when PED virus (PEDV) infection started in Slovenia. Serum samples collected between 2012 and 2016 were tested. Three hundred and seventy-five serum samples were collected from 132 Slovenian small, one-site pig farms. Samples were tested for PEDV antibodies utilising three different serological methods: commercially-available indirect ELISA, in-house blocking ELISA test and Immunoperoxidase Monolayer Assay (IPMA) test. One hundred and seventy (45.33%) tested samples were found positive by the commercially-available ELISA test kit, and 10 (5.68%) of these 170 samples found positive were positive by the in-house blocking ELISA. Only these 10 samples were collected from a farm where clinical signs of PED infection had been observed and PEDV was confirmed by RT-PCR methodology; the other 160 samples were collected randomly. Thirty-two samples with the highest S/P value obtained with the commercial ELISA were all negative with IPMA. Reasons for the high variance in the results obtained remain unclear; more research is required to ensure higher sensitivity and specificity in terms of PEDV antibody tests and other PED diagnostic methods.

Histological and Morphometric Examination of the Testes of Boars and Male Pigs Immunocastrated with Improvac

Background: Surgical castration of male piglets is frequently performed to prevent development of an unpleasant taste and flavor in meat of mature males, called boar taint. Disadvantages of this method are primarily related to the lower feed efficiency of surgically castrated male pigs, production of less lean meat and more fat on the carcasses than boars, as well as ethical issues associated with the procedure itself. Immunocastration is a method of immunization against gonadotropinreleasing hormone (GnRH) and represents an alternative to avoid boar taint. This study aimed to examine the influence of immunocastration on histological and morphometric parameters of male pig testes. Materials, Methods & Results: A total of 60 crossbred male pigs selected from 30 litters were assigned to two experimental groups: boars (n = 30) and immunocastrated males (n = 30). Two doses (2 mL per dose) of the Improvac® vaccine were given to pigs scheduled for immunocastration. The first injection was given at 10 weeks of age, and the second injection at 20 weeks of age. All pigs were fed the same commercial diet ad libitum, group-housed (15 pigs/pen) and slaughtered at 25 weeks of age. After slaughter, testicle weights were measured and samples of testicular tissue were taken for histological examination. Immunocastrated males had lower testicle weights than boars (P < 0.01). Furthermore, structural damage to the germinal epithelium was visible in the seminiferous tubules of vaccinated pigs. In the testicular interstitium of these animals, the number of Leydig cells were reduced; almost all of these cells exhibited different degrees of abnormality. Moreover, the diameter of the seminiferous tubules and thickness of the germinal epithelium were greater (P < 0.01), and the percentage of germinal epithelium in the seminiferous tubules as well as percentage of blood vessels in the interstitium were higher in boars as compared to immunocastrated males (P < 0.01). Seminiferous tubule lumen diameter was greater (P < 0.01), and percentage of lumen in the seminiferous tubules as well as percentage of non-blood vessel tissue in the interstitium were higher in immunocastrated males than boars (P < 0.01). Discussion: Vaccination against GnRH, as used in this study, reduced the synthesis of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which led to decreased spermatogenesis and androgen production. The smaller diameter of the seminiferous tubules as well as germinal epithelium thickness, and lower percentage of germinal epithelium in the seminiferous tubules in immunocastrated males could be explained by reduced FSH synthesis, and subsequent reduced spermatogenesis. The described testicular malformations in immunocastrated animals caused their lower weight, and greater diameter of the lumen as well as a higher lumen percentage of the seminiferous tubules. The vaccine reduced LH synthesis, so the Leydig cells of immunocastrated animals had lower activity than the same cells in boars. The percentage of blood vessels in the interstitium of boar testes was higher, which was related to the blood supply required for normal function of Leydig cells. It was concluded that differences existed in the structure of the seminiferous tubules and interstitium between boars and immunocastrated males , which were reflected in values of the examined histological and morphometric parameters. The development of these differences was related to the inhibition of GnRH synthesis and secretion.

Use of Isolation and Antibody Detection for Salmonella Assessment

Salmonella infections of swine are of concern for two major reasons. The first is the clinical disease (salmonellosis) in swine that may result, and the second is that swine can be infected with a broad range of Salmonella serovars that can be a source of contamination of pork products. The genus Salmonella is morphologically and biochemically homogeneous group of Gram-negative, motile, non-spore-forming, facultative anaerobic bacilli with peritrichous flagella (Griffith et al., 2006). According to their biochemical characteristics it is divided in two species Salmonella enterica and Salmonella bongori. Salmonella enterica is further divided in six subspecies. Regarding their antigenic structure of somatic (O), flagellar (H) and capsular (Vi) antigens they are divided in serovars. Traditionally the serovars of subspecies enterica, which account for more than 99.5% of isolated Salmonella strains, have names, while all the others are named by their antigenic formula only (Grimont and Weill, 2007). Final differentiation within serovars is carried out by phage typing, plasmid profiling, restriction endonuclease analysis and resistance patterns. Serovars Typhimurium, Derby, Saintpaul, Infantis, Heidelberg, Typhisuis and Choleraesuis may all occur in pigs (Taylor, 2006).