Some aspects of nematode infection in pigs from small herds

Two traditionally maintained, small herds from southern Poland, with 8 and 12 sows, respectively, were surveyed coprologically during 2006-2007. In one of the herds, while deworming a group of sows with levamisole, faecal samples were collected on Day -7, Day 0 (the day of treatment) and Day 10, in order to assess the therapeutic effect of the drug. Coprological investigation was performed also in 26 fatteners originating from other small farms and slaughtered in a local abattoir, with their intestines washed through for the presence of roundworms. In both herds examined, Ascaris suum and Oesophagostomum spp. were prevalent, whilst Trichuris suis appeared only very rarely. Mainly fatteners, replacement gilts and young sows were highly infected with A. suum. The roundworm occurrence in 2- 3-week-old piglets, with the intensity of 300 eggs per gram of faeces (EPG), indicated the possibility of parasite transmission to offspring very early in age. The highest level of Oesophagostomum spp. infection was observed in sows, but weaners were also much affected. For the group of dewormed sows, the mean faecal egg count reduction (FECR) was estimated to be 77.1- 80.4%, suggesting the presence of resistant nodular worms. A very high false-positive A. suum egg counts found in slaughtered animals (240 to 320 EPG) testified to a high contamination level of the environment of small piggeries, as well. Since the reciprocal transmission of parasites between pigs and poultry might occur, it implies that the flocks should be raised separately.

[The influence of skin parasite infection on the productivity of gilts at pig testing stations]

On the basis of skin scrapings collected together with cerumen from the inside of ears, the occurrence of a hidden mite and louse infection was assessed to evaluate its effect on the productive traits of gilts fattened during 1996-1997 at Pig Testing Stations (PTS). The productivity was highly influenced by the station factors. The low level of infection had, however, some negative effect in a few cases, and in few it was not clear, probably due to the phenomenon of resilience.

[Analyses of the population structures of Mallophaga infesting urban pigeons]

A total of 70 pigeons from Cracow area was examined and the representation of bird lice (Mallophaga) infesting them estimated. Mostly the populations of two dominant species: Columbicola columbae columbae (L.) and Campanulotes bidentatus compar (Burm.) were assessed. 47% of birds inspected had less than 100 specimens of Mallophaga, although the highest infested one had 900 specimens. Sex and age of pigeons did not influence the number of bird lice present, and only weak health condition of individuals allowed higher infestation. The sex structure of ectoparasites was balanced, with a slightly higher number of females during the year of study. The highest number of bird lice was detected in autunm and the larvae definitely predominated then, as well. Similar tendency was observed in C. c. columbae populations. The course of age dynamic of C. b. compar was somewhat different, having the peak in July, and the imago stage dominated in this species. The populations of in C. c. columbae showed developmental signs, whereas the population structures of C. b. compar gave evidence of their regression.

[Observations on the vitality of lice from dead pigeons]

Experiments were carried out in July, September, October 1993 and January 1994 on 48 dead pigeons kept in cold storage (refrigerating machine) and at a window. The behaviour of Mallophaga was observed. The insects left the feather after the cooling of the bird body, usually after 24 hours. The process lasted 3 days in cold storage conditions, while in outdoor (open-air) environment the Mallophaga were still alive for another 14 days. The vitality of Mallophaga is bigger in open-air, in moderately higher temperature and in warmer seasons of the year. The examined representants of three species dominating in infestation demonstrated varying suitability for survival in harder conditions. The reaction of Hohorstiella gigantea lata (PIAG.) to the drop of temperature was the fastest, while Columbicola columbae columbae (L.) reacted more slowly and the reaction of the Campanulotes bidentatus compar (BURM.) was the slowest. Also the reaction of larvae to falling temperatures was faster that that of the adult forms.