Duck body condition affects the number of parasites in the gastrointestinal tract, as evaluated with the Akaike information criterion.

The aim of the study was to determine the relationship between the body condition, and the number of parasites in the gastrointestinal tract of the tufted duck (Aythya fuligula), using the Akaike information criterion. Absolute and relative measurements of 197 ducks were taken. Liver mass was positively associated with the number of parasites in the duodenum (ß = 0.5). Heart mass affected positively the number of parasites in the rectum (ß = 2.3), the number of nematodes in the jejunum (ß = 7.45), the total number of trematodes (ß = 1.7), their number in the ceca (ß = 7.3) and rectum (ß = 4.2), and the number of cestodes in the ceca (ß = 8.2). Beak length influenced the number of nematodes in the rectum (ß = 1.7). Left tarsometatarsus length (ß = 1.4) and relative head height (ß = -2.0) affected the number of trematodes in the ceca. Tail length influenced negatively the number of cestodes in the ileum (ß = -0.2). Similarly, a ratio of body mass to body length was negatively associated with the total number of parasites (ß = -0.1), their number in the ceca (ß = -0.2) and rectum (ß = -0.3), the total number of trematodes (ß = -0.3), and their number in the ceca (ß = -0.5) and rectum (ß = -0.4). A ratio of keel-skin length to keel length affected differently the total number of parasites in the ceca (ß = 9.1), the number of nematodes in the jejunum (ß = -17.9) and the number of trematodes in the duodenum (ß = -5.8). A ratio of fat mass to body length affected the number of cestodes in the jejunum (ß = 1.8). The present study indicates some morphological and anatomical parameters that may be useful for determining the correlation between the body condition and the level of parasitic infection.

Lactation milk yield prediction in primiparous cows on a farm using the seasonal auto-regressive integrated moving average model, nonlinear autoregressive exogenous artificial neural networks and Wood's model.

OBJECTIVE: The aim of the present study was to compare the effectiveness of three approaches (the seasonal auto-regressive integrated moving average [SARIMA] model, the nonlinear autoregressive exogenous [NARX] artificial neural networks and Wood's model) to the prediction of milk yield during lactation. METHODS: The dataset comprised monthly test-day records from 965 Polish Holstein-Friesian Black-and-White primiparous cows. The milk yields from cows in their first lactation (from 5 to 305 days in milk) were used. Each lactation was divided into ten lactation stages of approximately 30 days. Two age groups and four calving seasons were distinguished. The records collected between 2009 and 2015 were used for model fitting and those from 2016 for the verification of predictive performance. RESULTS: No significant differences between the predicted and the real values were found. The predictions generated by SARIMA were slightly more accurate, although they did not differ significantly from those produced by the NARX and Wood's models. SARIMA had a slightly better performance, especially in the initial periods, whereas the NARX and Wood's models in the later ones. CONCLUSION: The use of SARIMA was more time-consuming than that of NARX and Wood's model. The application of the SARIMA, NARX and Wood's models (after their implementation in a user-friendly software) may allow farmers to estimate milk yield of cows that begin production for the first time.

Redescription of Quasiamidostomum Fulicae (Rudolphi, 1819) Lomakin, 1991 (Nematoda: Amidostomatidae), a Parasite of Fulica Atra (Gruiformes).

INTRODUCTION: Quasiamidostomum fulicae (Rudolphi, 1819) Lomakin, 1991, is a species of which the systematic position is still unclear, and it is reported in the literature under many synonyms. In the present study, an attempt has been made at establishing the ultimate systematic position of Quasiamidostomum fulicae against the backdrop of selected Amidostomatinae species. MATERIAL AND METHODS: The parasites were identified based on measurements of external and internal structures. Ecological analysis of Q. fulicae was carried out using the quantitative indices (frequency, prevalence, mean intensity, relative abundance, and dominance index). Statistical analyses (discriminant analysis) were performed on measurement data. RESULTS: The intestines of 77 coots were examined. They yielded a total of 398 parasites, including 67 identified as Q. fulicae. Both males and females were located in the muscular gizzard. The morphometric analysis of Q. fulicae in this study showed the dimensions of all the internal organs to be in agreement with measurements reported by other authors. The discriminant analysis, used to find the differences between the examined nematode species (Amidostomoides acutum, A. petrovi, A. monodon, Amidostomum anseris, and Quasiamidostomum fulicae), gave highly significant results (P < 0.0001) with respect to both males and females. CONCLUSION: The results justify the separation of Q. fulicae from the genus Amidostomum.

Morphological and ecological characteristic of Dicranotaenia stenosacculata Macko, 1988 (Cestoda, Hymenolepididae) recorded in Poland

During the parasitological examination of 288 wild ducks from north-western Poland, 18 tapeworms were found in the intestines (jejunum, ileum and rectum) of six birds, which, based on the structure of the scolex, internal organs and the presence of cirrus with an internal additional sac, were determinated as Dicranotaenia stenosacculata Macko, 1988. Tapeworms were found in two young females Bucephala clangula, one young female Aythya marila as well as two adult males Aythya fuligula. The aim of the study was to present the morphological and ecological characteristics of the species, recently discovered for the first time in the fauna of Poland.

Taxonomic structure of cestodofauna of two species of diving ducks Aythya fuligula and A. marila (Anseriformes: Aythyini) in north-western Poland

Diving ducks Aythyini Delacour et Mayr, 1945 are an interesting object of the parasitological studies because due to living in two environments (aquatic and terrestrial) and migrating over long distances, they can come into contact with many potential hosts for parasites. In the recent years, a decrease in the population of diving ducks has been observed, especially of the tufted duck and the scaup. Both of them remain the most common species found in the region of West Pomerania, so the presented research is limited to the parasitological studies of these two species of ducks. The aim of this study was to determine the taxonomic structure of the cestodofauna of two species of diving ducks, the tufted duck and the scaup, wintering in north-west Poland. The research material consisted of 14,734 tapeworms collected from digestive tracts of 256 birds, 174 tufted ducks Aythya fuligula (Linnaeus, 1758) and 82 scaups A. marila (Linnaeus, 1761). All identified tapeworms obtained from digestive tracts of the hosts belonged to the Hymenolepididae family (order Cyclophyllidea). A total of 25 species of 9 genera were identified in the cestodofauna of the tufted duck, while in the cestodofauna of the scaup: 12 species of 7 genera. During 10 years of studies out of all of the 26 recorded species, 6 have been found in Poland for the first time. Moreover, 13 new, unlisted parasite-host relationships have been identified: 7 in the digestive tract of the tufted duck and 6 in the scaup.

Tetrameres globosa (Linstow, 1879) (Nematoda, Tetrameridae) ­ a nematode of the Eurasian coot Fulica atra (Linnaeus, 1758) recorded for the first time in Poland

During parasitological studies of 23 Eurasian coot Fulica atra (Linnaeus, 1758), 91 nematodes were isolated. Three of them, found in the proventriculus, were identified as Tetrameres globosa (Linstow, 1879). This paper presents the morphological characteristics of the discovered males of T. globosa.

The use of selected statistical methods and Kohonen networks in the revision and redescription of parasites

Revisions and redescriptions of species and higher taxa have been known in parasitology since the first description of a parasite. Usually, they are based on standard morphometric methods or more modern genetic analysis. The former are not always sufficiently reliable, while the latter often require expensive equipment, pre-defined genetic markers, and appropriately prepared research material. They may be replaced by multivariate statistical methods, in particular discriminant analysis and cluster analysis, and Kohonen artificial neural networks included in data mining. This paper presents the examples of specific applications of these methods for the verification of the affinity of nematodes. The discriminant analysis showed that it was possible to statistically significantly discriminate individual nematode species, both for males and females, based on morphometric variables. This confirmed the previously assumed division of the species complex Amidostomum acutum into three distinct species. Similarly, hierarchical cluster analysis, used for the determination of coherent groups of nematode parasites, allowed the identification of relatively homogeneous clusters of nematode species depending on their circle of hosts, and groups of hosts.

Fluoride concentrations in the pineal gland, brain and bone of goosander (Mergus merganser) and its prey in Odra River estuary in Poland.

The aim of the study was to investigate fluoride concentrations in bone, brain and pineal gland of goosander Mergus merganser wintering in the Odra estuary (Poland) as well as in fish originating from its digestive tract. The fluoride concentrations were determined with potentiometric method. Medians of concentrations in goosander had the highest and the lowest values in pineal gland and brain (>760 and <190 mg/kg, respectively). Fluoride concentration in the pineal gland was significantly greater than in the bone and the brain of the duck. In fish, the fluoride concentration ranged from 37 to 640 mg/kg and significant correlation was revealed between the fluoride concentration and fish weight and length. Based on own results and data of other authors, a daily fluoride intake by the goosander in the Odra estuary was estimated at 15 mg. So high fluoride concentrations like in the duck have not been found in mammal brains.

Cloacotaenia megalops (Nitzsch in Creplin, 1829) (Cestoda, Hymenolepididae) in wild ducks in Western Pomerania, Poland.

Cloacotaenia megalops (Nitzsch in Creplin, 1892) is a polyxenic and cosmopolitan tapeworm from the family Hymenolepididae. Its generic name derives from their typical location (cloaca), and the typical final hosts which are birds typically associated with water and marsh environments: Anseriformes, Galliformes and Gruiformes. In Poland, the presence of C. megalops has been observed so far in 16 species of ducks from the Baltic coast, the Mazurian Lake District, Wielkopolsko-Kujawska Lowland, Mazovian Lowland, and Podlasie Lowland. In Western Pomerania, quantitative structure analyses were only carried out on Anas platyrhynchos, and therefore the aim of this study was the detailed analysis of environmental populations of C. megalops in wild ducks. The examined tapeworms were isolated from the digestive tract of 1005 wild ducks representing 17 species belonging to three different eco-tribes: Anatini (n=225), Aythyini (n=413) and Mergini (n=367), from northwestern Poland. During the Study 187 C. megalops were found in 89 birds (8.8% of examined ducks) belonging to 7 species: Anas crecca (common teal), A. querquedula (garganey), A. platyrhynchos (mallard) (Anatini); Aythyaferina (pochard), A. fuligula (tufted duck), A. marila (greater scaup) (Aythyini) and Bucephala clangula (goldeneye) (Mergini). The results show the differences in the quantitative structure of C. megalops among the examined species of ducks. The highest prevalence was found in mallard (18.6%) and the lowest in greater scaup (3.2%). The highest mean intensity was observed in greater scaup (4.0), and the lowest in garganey and common teal (1.0). Relative density was at a similar level in the tested birds. Based on the ratio of dominance, it was found that C. megalops is a rare species in the cestodofauna in the examined birds.

Morphological features of Cloacotaenia megalops (Nitzsch in Creplin, 1829) (Cestoda, Hymenolepididae) from different hosts.

The tapeworm species Cloacotaenia megalops (Nitzsch in Creplin, 1829) is characterized by a very specific morphology. A particularly distinct feature is a large almost square scolex in which four fleshy suction cups are embedded and a rudimentary rostellum. During standard studies of wild duck cestode fauna in northwestern Poland, some morphological differences were observed among specimens, mainly in the shape of scolices and hermaphroditic proglottids of C. megalops isolated from different bird species. This paper attempts to demonstrate the impact of the host species on morphology of the parasite. The study material consisted of 39 individuals of C. megalops (19 from Aythya fuligula, 10 from Anas platyrhynchos, 4 from Bucephala clangula, 4 from Aythya marila and 2 from A. ferina). The isolated parasites were fixed and stored in 70% ethanol and solid preparations were made. Selected external and internal structures of the parasite were measured and photographed using a Zeiss microscope, a microscope camera Opta Tech 2.1 and Opta View 6.0.2.2. It was stated that the sizes of the most important elements of the parasite morphology are generally consistent with those presented in the available literature, nevertheless some differences were observed in both morphology and sizes of some anatomical structures, especially in the form of scolices and hermaphroditic proglottids between specimens isolated from hosts representing three different eco-tribes (Aythyini, Anatini and Mergini).

Revision of the species complex Amidostomum acutum (Lundahl, 1848) (Nematoda: Amidostomatidae).

Most available literature indicates that the most dominant nematode in Anatinae is a cosmopolitan species Amidostomum acutum (Lundahl, 1848). However, studies on wild duck helminthofauna in northwestern Poland suggest that these birds are attacked by not one but three different parasite species, previously described as a single species. Hence the aim of this study was the redescription of the species complex Amidostomum acutum, conducted on a representative sample of parasites and their hosts. The study material consisted of 6,430 nematode individuals, isolated from the digestive tracts of 1,005 wild ducks, representing 17 species. Unsupervised classification was performed using a Kohonen artificial neural network. The analysis confirmed the division of nematodes into three groups corresponding to three species, both for males and females. Taking into account the qualitative characteristics of the parasites, one can 100% accurately identify these species. The three groups of parasites were also significantly different in their ecology, manifested in their distinct host specificity.

[First record of species Dicranotaenia synsacculata Macko, 1988 (Cestoda, Hymenolepididae) of the goldeneye Bucephala clangula (Linneus, 1758) in Poland]. / Dicranotaenia synsacculata Macko, 1988 (Cestoda, Hymenolepididae)--tasiemiec gagola Bucephala clangula (Linneus, 1758) notowany po raz pierwszy w Polsce.

During parasitological studies of 32 specimens of the goldeneye Bucephala clangula L., twenty seven cestode specimens were found. Four of them, isolated from the jejunum of two young female hosts, were determinated as Dicranotaenia synsacculata Macko, 1988. We based on the shape of cirrus fused with sacculus accessorius internus, shape and size of scolex and other organs. This is the first record of this species in Poland.

[First record of Microsomacanthus tuvensis Spasskaya et Spasskii, 1961 (Cestoda, Hymenolepididae) in Poland]. / Microsomacanthus tuvensis Spasskaya et Spasskii, 1961 (Cestoda, Hymenolepididae) po raz pierwszy notowany w Polsce.

During standard parasitological studies of the tufted duck Aythya fuligula, obtained from fishermen from West Pomerania in December 2007, three cestode specimens were found in the jejunum of one male host. They were determinated as Microsomacanthus tuvensis (Spasskaya et Spasskii, 1961) on the basis of the cirrus's and cirrus sac's size and vagina's shape. This is the first record of this species in Poland.

[Helminthofauna of the goosander Mergus merganser L., 1758 from the north-western Poland]. / Helmintofauna nurogesi Mergus merganser L., 1758 z pólnocno-zachodniej Polski.

The goosander, Mergus merganser, is a rare in Poland water bird (Anseriformes: Mergini). It eats fish and small invertebrates. The purpose of this study was a preliminary parasitological examination of the digestive tract of the goosander wintering on the Szczecin Lagoon. The research material were the parasites recovered from digestive tracts of 6 birds (two males and four females), which died during feeding in fishing nets in winter 2001. The birds were subject to standard parasitological examinations using commonly adopted methods. The trematodes and the cestodes found were preserved in 70% ethyl alcohol and subsequently stained using iron carmine (Cestoda) and borax alcohol carmine (Digenea) and then they were closed in Canada balsam. Nematodes were kept in 70% alcohol and cleared with 80% lactic acid or lactophenol. The parasite assemblages were analysed through calculating prevalence, intensity of infection, relative density and domination index. Also, the topic structure of the parasite assemblages or their habitat preferences in a host animal digestive tract were determined. The presently reported study detected a total of 1596 parasitic worms: digeneans (1086), tapeworms (410) and nematodes (100). Acanthocephalans were not found. Even though only a few goosanders were examined, the results show a high species richness of parasite assemblages consisting of 22 species, representing 21 genera. The following were deemed as definite dominants (superdominants): Diplostomum mergi Dubois, 1932; D. pusillum (Dubois, 1928); Microsomacanthus abortiva (von Linstow, 1904) and Schistocephalus solidus (Müller, 1776). Helminths were found in all birds with their great relative density and intensity of occurrence (266 parasites on average). As expected, the parasite assemblages were characterized by considerable topical specificity, probably resulting from the feeding preferences of the worms. The majority of helminths, including predominant part of flatworms, were found in duodenum and jejunum of ducks. Nematodes, on the other hand, colonized mainly the gizzard and proventriculus.

[First record of species Microsomacanthus oidemiae Spassky et Jurpalova, 1964 (Cestoda: Hymenolepididae) in wild ducks of north-western Poland]. / Microsomacanthus oidemiae Spassky et Jurpalova, 1964 (Cestoda: Hymenolepididae)--tasiemiec po raz pierwszy notowany u dzikich kaczek pólnocno-zachodniej Polski.

The presently reported study on cestodofauna of wild Anatinae of north-western Poland showed the presence of at least a dozen or so cestodes, hitherto unrecorded in Polish fauna. One of them is Microsomacanthus oidemiae Spassky et Jurpalova, 1964 (Hymenolepididae). This parasite (two not fully developed individuals, including one without a scolex) was found in the common scoter, Melanitta nigra L., (Mergini) wintering on Lake Dabie near Szczecin.

[Aythya fuligula--new host for Retinometra pittalugai Lopez-Neyra, 1932 (Cestoda, Hymenolepididae) recorded in Poland for the first time]. / Aythya fuligula--nowy zywiciel dla tasiemca Retinometra pittalugai Lopez-Neyra, 1932 (Cestoda, Hymenolepididae) po raz pierwszy notowanego w Polsce.

During standard parasitological studies of the tufted duck Aythya fuligula (Linnaeus, 1758), obtained from fishermen from West Pomerania, three cestode specimens were found in the jejunum of hosts. They were determined as Retinometra pittalugai (Lopez-Neyra, 1932) on the basis of the cirrus's size, shape of stylet and rostellar hooks. This is the first record of this species in Poland, since this parasite was earlier recorded only in Anas platyrhynchos f. dom., Aythya marila, A. ferina and Bucephala clangula in Spain, in Kamchatka and in Novosibirsk.

[Digenea of Haliaeetus albicilla (Linnaeus, 1758) and Pandion haliaetus (Linnaeus, 1758) from middle and north-western Poland]. / Digenea Haliaeetus albicilla (Linnaeus, 1758) i Pandion haliaetus (Linnaeus, 1758) ze srodkowej i pólnocno-zachodniej Polski.

In 2003-2008 eight white-tailed eagles and two ospreys from middle and north-western Poland were examined for the presence of parasites. Nine birds were infected with 5 digenean species: Conodiplostomum perlatum, Paracoenogonimus ovatus, Strigeafalconis, Metorchis crassiusculus and Nematostrigea serpens. M. crassiusculus was found for the first time in an eagle from Poland.

[Intestinal digeneans of Gavia stellata (Pontoppidan, 1763) and Gavia arctica (Linnaeus, 1758) from West Pomerania, Poland]. / Digenea ukladu pokarmowego Gavia stellata (Pontoppidan, 1763) i Gavia arctica (Linnaeus, 1758) z Pomorza Zachodniego.

In 2000 and 2006 a total of 20 divers including 15 Gavia stellata and 5 Gavia artica from Pomeranian Bay and Szczecin Lagoon were examined. G. stellata were found to be infected with 3 digenean species: Stephanoprora pseudoechinata (Olsson, 1876), Cryptocotyle concava (Creplin, 1825) and Diplostomum gavium (Guberlet, 1922). G. arctica were host to Echinochasmus spinulosus (Rudolphi, 1809). This is the first record of Stephanoprora pseudoechinata in G. stellata and Echinochasmus spinulosus in G. arctica in Poland. The prevalence of S. pseudoechinata infection (46.7%) was higher than that of other digeneans.