Association of a melanocortin 4 receptor (MC4R) polymorphism with performance traits in Lithuanian White pigs

The melanocortin 4 receptor is expressed in virtually all brain regions of mammals and plays an important role in energy homeostasis. Polymorphisms in this gene may thus be related to growth and obesity. In pigs, a non‐synonymous polymorphic site was described (Asp298Asn) and demonstrated to affect cAMP production and to alter adenylyl cyclase signalling. Association studies revealed significant linkage of this mutation with production trait in pigs. In this study, 207 Lithuanian White pigs were genotyped at the MC4R locus and analysed on relationships between genotype and breeding values for several performance traits. The observed allele and genotype frequencies did not deviate significantly from Hardy–Weinberg equilibrium (wildtype allele 0.59; mutant allele 0.41) and are comparable with those described in other Large White populations. The mutant Asn298 allele of the MC4R gene was significantly associated with increased test daily gain, higher lean meat percentage and lower backfat thickness. There was a trend towards an improved feed conversion ratio (p = 0.065) in animals with the mutant allele whereas no significant effect was found on lifetime daily gain. These results indicate that the MC4R polymorphism should be integrated in selection programmes in the Lithuanian White to improve carcass composition.     

The impact of storm water runoff on a small urban stream

Background, aim, and scope  In urban areas, storm water runoff often transports various pollutants, some of which settle and form sediments. In order to have the comprehensive view of the ecological state of storm water runoff recipients, both water and sediments of the stream must be assessed. In the Baltic Sea Area, the Water Framework Directive & HELCOM Recommendations aim to prevent or minimise pollution caused by harmful substances arising from storm water runoff, in order to promote the ecological restoration of the Baltic Sea—one of the most vulnerable seas. The aim of the study was to investigate the toxicity of bottom sediments of a small storm water runoff recipient focusing on the potential impact of successive discharges of urban storm water. Some storm water runoff quality parameters and the toxicity of bottom sediments of recipients was studied in this research. Materials and methods  During 9 years, at four discharge points, minimum four grab samples per year at each discharge point were taken for chemical characterisation. General parameters (pH, SS, BOD₇, COD_Cr and TPH) in liquid phase samples were analysed according to standard methods. Annual limit values were taken from the Lithuanian EPA requirements for the management of storm water runoff with a focus on prevention and control of contamination. Eleven composite samples of stream bottom sediments, each consisting of ten sub-samples, were collected in 2006. Toxicity screening from sediments was performed using the plant Lepidium sativum according to modified I. Magone’s methodology (Magone I, Bioindication of phytotoxicity of transport emission. In: Kachalova O-L, Zinatne (eds) Bioindication of toxicity of transport emissions in the impact of highway emissions on natural environment. Riga, pp 108–116, 1989). The level of toxic impact of Lepidium sativum (compared to control) was assessed according to the modified method of Wang (Rev Environ Contam Toxicol 126:88–127, 1992). Results  The mean pH of urban storm water runoff does not vary much from neutral, but range values are quite different, from 4.0 up to 8.7. The highest concentration of SS reached 800 mg L⁻¹, TPH—2.4 mg L⁻¹, BOD₇—300 mg O₂ L⁻¹ and COD_Cr—1,400 mg L⁻¹. The SS was above the limit in 64% of total amount of grab samples, TPH—37%, BOD₇—41% and COD_Cr—55%. The toxicity analysis of the bottom sediments showed varying toxicity of bottom sediments along the stream. From nine analysed samples of bottom sediments, 30% had weak toxicity, 30% medium and 30% strong toxicity on the test organism plant L. sativum. There was one single sample with no toxic effects, so that the results showed that urban storm water has an unacceptable environmental impact on recipients. It was also indicated that storm water runoff discharge alone is not the potential source of toxicity of bottom sediments. The litter demonstrated a weak toxicity of bottom sediments as well. Discussion  Most local authorities do not consider storm water runoff discharges to be a matter of great concern because they believe that surface runoff arising from rainfall is still relatively clean. The study showed that the current method of monitoring storm water runoff quality by chemical analyses is not the best tool for environmental impact assessment and must be combined with toxicity tests of bottom sediments of recipients. Recommendations and perspectives  To avoid the environmental impact of storm water runoff more attention should be paid to the development and implementation of storm water runoff pollution prevention measures. The study implies that future research concerning the relationships between storm water runoff deposit characteristics and biological activities must be developed to evaluate the contamination potential of stream sediment deposits for local aquatic ecosystems. Further studies should be developed to characterise the activities of the microbial community of storm water runoff sediments, and to monitor bioremediation in situ.     

Prevalence,species distribution and antimicrobial resistance patterns of methicillin-resistant staphylococci in Lithuanian pet animals

Background

The bacterial genus Staphylococcus consists of many species that causes infections in pet animals. Antimicrobial resistant staphylococci cause infections that are difficult to treat and they are important from the point of one health perspective. The aim of this study was to determine the prevalence of methicillin-resistant Staphylococcus (MRS) species, including methicillin-resistant S. aureus (MRSA) in diseased pet animals (Group A) and kennel dogs (Group B) in Lithuania and to characterize the isolates according to their antimicrobial resistance.

Results

Twenty-one MRS isolates were obtained from 395 clinical samples (5.3 %; CI 95 % 3.5-8.0) of Group A animals. Sixteen, four and one isolates were from dogs, cats and a pet rabbit, respectively. The mecA gene was present in 20 isolates, whereas one isolate was positive for the mecC gene. Twenty-one MRS isolates (20.0 %; CI 95 % 13.5-28.6) were obtained from the vagina of female dogs (n = 105) (Group B). All isolates carried the mecA gene. Twelve MRS species were isolated of which S. pseudintermedius was the most common (18/42) followed by S. haemolyticus (8/42) and S. lentus (4/42). MRSA was not found. All MRS strains were susceptible to vancomycin, linezolid, daptomycin and quinupristin/dalfopristin. Resistance to tetracycline (16/21), clindamycin (15/21) and erythromycin (14/21) was the most common types of resistance in Group A animals. Three isolates also demonstrated resistance to rifampin. Resistance toward gentamicin (16/21), ciprofloxacin (15/21), macrolides (15/21) and tetracycline (12/21) was the most common in kennel dogs (Group B). The most common genes encoding resistance to antimicrobials (excluding beta-lactams) in isolates from Group A pets were tetK (21/42), aph(3′)-IIIa (11/42) and aac(6'')-Ie-aph(2'''')-Ia (9/42).

Conclusions

A wide range of MRS species were found in pet animals in Lithuania. MRSA was not found.     

Prevalence,quantitative load and genetic diversity of Campylobacter spp. in dairy cattle herds in Lithuania

Background

Campylobacteriosis is a zoonotic disease, and animals such as poultry, pigs and cattle may act as reservoirs for Campylobacter spp. Cattle shed Campylobacter spp. into the environment and they can act as a reservoir for human infection directly via contact with cattle or their faeces or indirectly by consumption of contaminated food. The aim of this study was to determine the prevalence, the quantitative load and the genetic strain diversity of Campylobacter spp. in dairy cattle of different age groups.

Results

Faecal samples of 200 dairy cattle from three farms in the central part of Lithuania were collected and examined for Campylobacter. Cattle herds of all three farms were Campylobacter spp. positive, with a prevalence ranging from 75% (farm I), 77.5% (farm II) to 83.3% (farm III). Overall, the highest prevalence was detected in calves (86.5%) and heifers (86.2%). In contrast, the lowest Campylobacter prevalence was detectable in dairy cows (60.6%). C. jejuni, C. coli, C. lari and C. fetus subsp. fetus were identified in faecal samples of dairy cattle. C. upsaliensis was not detectable in any sample. The high counts of Campylobacter spp. were observed in faecal material of dairy cattle (average 4.5 log₁₀ cfu/g). The highest numbers of Campylobacter spp. were found in faecal samples from calves (average 5.3 log₁₀ cfu/g), whereas, faecal samples from cows harboured the lowest number of Campylobacter spp. (average 3.7 log₁₀ cfu/g). Genotyping by flaA PCR-RFLP analysis of selected C. jejuni isolates showed that some genotypes were present in all farms and all age groups. However, farm or age specific genotypes were also identified.

Conclusions

Future studies are needed to investigate risk factors related to the degree of colonisation in cattle. Based on that, possible measures to reduce the colonisation and subsequent shedding of Campylobacter in cattle could be established. It is important to further investigate the epidemiology of Campylobacter in the cattle population in order to assess associated risks to public health.