Selected Nutrients and Iron in Interstitial Waters of the Estuary of Southern Baltic (Gulf of Gdañsk and the Pomeranian Bay) in Relation to Redox Potential

The following parameters were determined in the interstitial waters of the Gulf of Gdańsk and the Pomeranian Bay: nutrients (ammonia and phosphates), sulphates, total iron and iron(II) concentrations. Redox potential (Eh), pH, humidity and organic matter content measured as a loss on ignition were determined in bottom sediments from these regions. Interstitial waters of both regions were found to have reducing character (Eh < 250 mV). Reduction processes were more advanced in the Gulf of Gdańsk, rich in organic matter, as evidenced by lower values of the redox potential, lower Fe(III)/Fe_tot ratio, and incidents of sulphates exhaustion.     

Profile Distributions of Lead,Zinc, and Copper in Dystric Cambisols Developed from Granite and Gneiss of the Sudetes Mountains,Poland

Total contents of Pb, Zn and Cu were examined in twenty-five soilprofiles of forested Dystric Cambisols developed from granite andgneiss in the area of the Sudetes Mountains (SW Poland). Sequential extraction of heavy metals was also carried out to study relations between metal content and soil compounds. Profile distribution differed among the metals examined: Pb concentrations decreased gradually from surface with depth, whereas those of Zn increased with depth of soil profile, obtaining their maximum in the bedrock horizon. Cu was found to accumulate in topsoil and decrease with depth, but showed secondary increase of the concentration in bedrock. Organic matter was found to be a crucial factor of Pb binding and distribution, while iron oxides played the most important rolein Zn binding. Both organic matter and oxides were important factors of Cu distribution. The results of sequential extractionshow that all studied elements are mobile under strong acidicconditions in investigated Cambisols. Thus, total contents of Zn and Cu in bedrock cannot be used as geochemical background or as reference levels for assessing the contamination of soilsurface with these metals.     

Supplementation of maca (Lepidium meyenii) tuber meal in diets improves growth rate and survival of rainbow trout Oncorhynchus mykiss (Walbaum) alevins and juveniles

Maca tuber meal is used in fish diet formulations in Andean trout culture and knowledge of its effects on fish growth is paramount to healthy human food production. In the first experiment with rainbow trout alevins (0.096±0.002 g), starter diets were offered from first feeding until 15 weeks. We formulated high protein content (～60%) semi‐purified starter diets supplemented with 0%, 5%, 10%, or 15% maca tuber meal (control, M‐5, M‐10, and M‐15 respectively). The second feeding trial was conducted with juveniles (1.56±0.02 g) fed one of three diets (control, M‐15, and commercial) for 8 weeks. In the first experiment, fish fed M‐10 and M‐15 diets exhibited significantly higher growth rates than the other dietary groups. Survival was significantly improved in the groups fed diets supplemented with maca tuber meal (60.0–69.2%) in comparison with the group fed a control diet (21.7%). The second experiment showed a higher growth rate in the M‐15 group compared with the control and a commercial diet fed group. Leucocyte numbers were increased by dietary supplementation of maca tuber meal. The findings of the present study suggest that a maca tuber meal inclusion at least 5% improves growth rate, feed utilization, immunity by increased leucocyte number, and survival of rainbow trout alevins and juveniles.     

The bovine CXCR1 gene is highly polymorphic

Several single nucleotide polymorphisms (SNP) in the bovine CXCR1 gene have been implicated in resistance to mastitis and milk somatic cell counts in several sample populations of Holstein dairy cows. As such, a more thorough understanding of SNP present in and near the bovine CXCR1 gene is needed. This study identified 36 SNP in the coding region and surrounding sequences of CXCR1 in 88 Holstein dairy cows. Four SNP induced amino acid changes and 1 SNP an early stop codon. Two amino acid changes occur in the third intracellular loop and C-terminus in locations tied to intracellular signaling. The 36 SNP could be subdivided into 4 separate linkage groups. Using representative or 'tag' SNP from each linkage group, haplotypes or the combination of SNP found on a single allele were generated to increase the specificity of an animal's genetic background. Four haplotypes were identified that represented 99% of the sample population. The haplotypes generated using tag SNP agreed with haplotypes generated from SNP causing amino acid changes. In conclusion, the CXCR1 gene is highly polymorphic and has potential implications towards genetic selection and understanding host factors that increase the risk of infection.     

Selected leukocyte subpopulations in peripheral blood and uterine washings in cows before and after intrauterine administration of cefapirin and methisoprinol

The aim of the study was to evaluate the selected lymphocyte subpopulations TCD4, TCD8, BCD21, BCD25, CD18, CD11b, and MHC II in blood and uterine flush of cows with endometritis, before and after intrauterine (i.u.) administration of cefapirin and methisoprinol. The research was carried out on 28 cows with clinical endometritis. Animals were divided into four groups, each composed of seven cows, depending on the i.u. preparation used: Group A, cefapirin; Group B, methisoprinol; Group C, cefapirin and methisoprinol simultaneously; and a control group—without medication. The study was performed using flow cytometry method. Summarizing the results of the research, i.u. infusion of cefapirin caused a weakening of the effector phase of the local uterine immune response; however, it enhanced leukocyte chemotaxis and antigen presentation. After i.u. administration of methisoprinol, the stimulation of specific uterine immunity mechanisms was mainly observed. The use of both mentioned preparations showed the strengthening of specific uterine immunological mechanisms presumably caused by methisoprinol, despite the inhibitory effect of the antibiotic. Intrauterine use of immunostimulatory substances can improve the effectiveness of the endometritis treatment in cows by improving specific local mechanisms of uterine immunity. As a consequence, it may enhance the effector function of immune competent cells and finally eliminate inflammation.     

Dynamics of the root/soil pathogens and antagonists in organic and integrated production of potato

Microbial communities in the root, rhizoplane, and rhizosphere and non-rhizosphere soil in potato, in organic and integrated production systems, were compared at the emergence and flowering phases of plant development. Microorganisms were identified on the basis of their morphology. The dominant groups included Clonostachys + Gliocladium + Trichoderma, Fusarium + Gibberella + Haematonectria + Neonectria, Paecilomyces, Penicillium and Phoma. Microbial density at the flowering phase was often significantly greater in roots and non-rhizosphere soil than in the rhizoplane and rhizosphere. Diversity of the communities often remained stable or was greater at the emergence phase. The density of bacteria changed with time. The density of Pseudomonas often decreased while Streptomyces significantly increased with time. Changes in densities of pathogens and antagonists decreased the suppressiveness of the habitat towards soil-borne potato pathogens at the flowering phase. The study contributes information that will help to: (a) understand the epidemiology of some potato diseases, (b) make decisions on the economic and ecological aspects of chemical control in potato, (c) develop strategies for manipulation of the soil microbial environment as a viable crop management technique, and (d) develop prognosis models for potato diseases in central Europe.     

Prey decline leads to diet shift in the largest population of Indo-Pacific humpback dolphins?

The Pearl River Delta (PRD) region on the southeast coast of China has long been known as a highly productive fishing ground. Since the late 1980s, fishing pressure in the PRD has been intense, which warrants concerns of potential fishery-related impacts on the food resources and foraging ecology of apex marine predators in this region, such as the Indo-Pacific humpback dolphin (Sousa chinensis). In this study, we examined 54 stomachs with food remains, collected from beached carcasses of humpback dolphins recovered during fifteen years between 2003 and 2017. The 6043 identified prey items represent 62 teleost taxa, primarily small estuarine fish, but also larger reef fish. The dolphins appear to be opportunistic foragers, hunting across the water-column, with preference for shoaling and meaty fishes (e.g. Collichthys lucidus IRI% = 38.6%, Johnius belangerii IRI% = 23.1%, Mugil cephalus IRI% = 14.0%). Our findings suggest a dietary shift in recent years, from primarily demersal (as previously reported) to greater intake of neritic and pelagic fish. Dolphin foraging group size has decreased in recent years, which corresponds with declining size and numbers of prey items retrieved from dolphin stomachs. We suggest that these are indicators of declining food resources. Faced with a shortage of preferred prey, humpback dolphins may have broadened their dietary spectrum to maintain their daily energy intake, while their foraging group size decreased in response to the altered tradeoff between the costs and benefits of group foraging.     

Photo-identification comparison of four Indo-Pacific humpback dolphin populations off southeast China

Indo-Pacific humpback dolphins (Sousa chinensis) inhabit shallow coastal waters of the Indo-Pacific region including southeast China, with at least 6 putative populations identified to date in Chinese waters. However, the connectivity among these populations has not yet been fully investigated. In the present study, we compared and cross-matched photographic catalogs of individual dolphins collected to date in the Pearl River Delta region, Leizhou Bay, Sanniang Bay, and waters southwest of Hainan Island, a total of 3158 individuals, and found no re-sighting of individual dolphins among the 4 study areas. Furthermore, there was a notable difference in the pigmentation pattern displayed by individuals from these 4 regions. We suggest that this may be a phenotypical expression of fine-scale regional differentiation among humpback dolphin groups, possibly distinct populations. Given the considerable conservation management implications it may carry (e.g. definition of management units), further research is much needed.