Trematode cataract in fresh water fish

Abstract— —The occurrence of cataract in fresh-water fish has recently been the cause for increasing concern amongst anglers who have been catching a steadily falling number of fish in several regions. It has been known for over 100 years that certain fish may become infested with a trematode (or fluke) which has a remarkable predilection for the lens. The life cycle begins in the intestine of the seagull where the adult trematode produces ova which are excreted on to the waters of reservoirs and lakes. The ova hatch out into miracidia which in turn invade water snails to form a sporocystic stage. Cercariae emerge from the snail and swim free to burrow into the body of a fish and find their way to the crystalline lens. The cycle is completed by the consumption of the fish by the gull in which the adult trematode once more develops. The purpose of this communication is to demonstrate the histological changes produced in the lens by the trematode. Résumé— —L'augmentation de l'incidence de la cataracte du Poisson d'eau douce a été récemment la cause de l'inquiétude croissante des pécheurs qui prennent une quantité sans cesse diminuée de Poisson dam différentes régions. Il est connu depuis plus de cent ans que certains poissons peuvent être infectés par les trématodes (ou douves) qui se logent avec une nette prédilection dans le cristallin. Le biocycle débute dam l'intestin de la mouette ou le trématode adulte pond des oeufs qui sont excrétés dans les eau des réservoirs et des lacs. Les oeufs donnent naissance am miracidies qui à leur tour envahissent les escargots d'eau et s'y transforment en sporocystes. La cercaire se libère de l'escargot et nage librement pour se loger dans le corps d'un Poisson et se frayer un chemim jusqu'au cristallin. Le cycle est achevé par l'ingestion du Poisson par la mouette chez laquelle le trématode adulte continue à se développer. Le but de cet article est de décrire les lésions histologiques du cristallin produites par le trématode. Zusammenfassung— —Das Auftreten von Katarakten bei Süsswasserfischen gab vor kurzem Anlass für steigende Besorgnis unter Anglern, die in mehreren Gebieten nur eine ständig abnehmende Zahl von Fischen fingen. Es ist seit über 100 Jahren bekannt, dass bestimmte Fische von Trematoden (Saugwürmer) befallen werden können, die eine merkliche Bevorzugung der Augenlinse zeigen. Der Lebenszyklus beginnt im Darm der Seemöwe, wo die envachsenen Trematoden Eier legen, die auf Wasserflächen von Staubecken und Seen ausgeschieden werden. Aus den Eiern gehen Mirazidien hervor, die ihrerseits Wasserschnecken befallen und dort ein sporozystisches Stadium bilden. Aus den Schnecken gehen dann Zerkarien hervor, die frei umherschwimmen und nach dem Eindringen in den Körper eines Fisches den Weg in die Augenlinse finden. Der Zyklus wird dadurch gesch-lossen, dass die Möwe den Fisch frisst und dass sich in dem Vogel abermals die erwachsenen Trematoden entwickeln. Der Zweck dieser Mitteilung besteht in der Beschreibung der histologischen Veranderungen, die von den Trematoden in der Linse hervorgerufen werden.     

Rickets in growing pigs and response to treatment

The clinical, radiological and pathological findings in a natural outbreak of rickets affecting 82 pigs are described. An interesting feature was the presence of gross articular abnormalities including resorption of subchondral bone with folding and ulceration of the articular cartilage. The diet was deficient in calcium and vitamin D. A diagnosis of rickets complicated by nutritional secondary hyperparathyroidism was made. The results of treatment and the economics of the outbreak are discussed.     

The response of pigs to being loaded or unloaded onto commercial animal transporters using three systems

Groups of pigs were subjected to three different systems of loading and unloading to and from commercial animal transporters. The systems under trial were: the use of a hydraulic tail-lift, a tail board ramp at an angle of 18 degrees and a modular system. The module was a container 2 m x 2.4 m x 1 m high into which the pigs were loaded. The module could then be lifted on and off the lorry with a fork lift truck. Non-invasive monitoring techniques were used to study the responses of the pigs. A subjective handling score, time taken to load and unload, skin temperature, heart rate and salivary cortisol were recorded. Loading and unloading were subjectively assessed as being easiest and quickest using the modular system, which also appeared to be less physically demanding for the animals, as evidenced by lower heart rate and a reduced maximum heart rate. However, with the modular system, elevated cortisol was found during the loading, unloading and resting periods. This could be interpreted as indicating that the pigs were unable to settle in the module and suffered some small degree of stress, which might become more of a problem during prolonged transport. Of the other two systems, there appeared to be little difference between the hydraulic tail-lift and the ramp.     

Ovarian remnant syndrome: revascularization of free-floating ovarian tissue in the feline abdominal cavity

Nine, healthy, intact female domestic shorthair cats were ovariohysterectomized. At the time of surgery and following removal, the major portion of one ovary was loosely sutured to the mesentery and replaced in the abdominal cavity. Six months later, an abdominal laparotomy was performed in order to retrieve the ovarian remnants. Histopathological examination of the remnants showed viable tissue and evidence of ovarian follicles or corpora lutea in eight of nine (88.9%) cats. The ninth ovarian remnant was atrophied and fibrotic. Measurement of serum estradiol and progesterone, vaginal cytology, and stimulation of estrus and ovulation with a protocol using pregnant mare serum gonadotropin (PMSG) followed by human chorionic gonadotropin (hCG) were unreliable indicators of ovarian activity in this study. Revitalization of an ovarian remnant was shown to occur in the absence of surgical implantation.