Symposium: Neonatal Diseases of the Dog: III: Thermal Regulation in the New-born Dog*

Abstract— Defects in thermal regulatory mechanisms of the new-born dog are described with particular reference to the relative absence of true chemical regulation of body temperature during the first 2–3 days of life. This deficiency is partly compensated by the ability to absorb heat from external sources. Some of the clinical signs of health of the day-old puppy are given together with signs of progressive hypothermia which can develop under natural conditions.     

Embryogenetics: gene control of the embryogenesis of the eye

In recent years there have been significant advances in our knowledge and understanding of the genetic control of embryonic development. The aim of this paper is to review the current state of knowledge regarding genetic control of embryogenesis, the first stage of ocular development. Products of numerous genes participate in signaling, induction and control during the formation of the neural plate, groove and tube, key events leading to the development of the future eye.     

Towards the standardization of the abbreviations of genus names of ticks (Acari: Parasitiformes: Ixodida)

An abbreviation system for genus names of ticks of the world is proposed. This abbreviation system adopts two letters (typically, the first two), as previously proposed for Culicidae and more recently for Phlebotominae. I hope this abbreviation system will be useful for anyone interested in tick taxonomy and related areas.     

Genetics of racing performance in the Japanese Thoroughbred horse:: I. Description of the data

SUMMARY: The Japan Racing Association (JRA) operates 10 national racecourses with both turf and dirt tracks. JRA formulates the rules for horseracing; registers owners, colors, and horses using foal registration; and licenses all JRA trainers and jockeys. In 1990, at the 10 racecourses there were 288 racing days, 3,353 races, and some 38,397 horses. Horse breeding is concentrated in 7 locations with 93% of the Thoroughbreds foaled each year coming from Hokkaido. Thoroughbred flat racing comprise 92% of all races held. Two year olds race together and nearly 40% of their races are run at 1200 m. Some 39% of the three year olds races are at 1800 m. For 3 (and 4) year olds, the range in distances is from 1000 m to 3600 m. The average, over years, of the number of race records per race for 2 year olds is 10.0 and for 3 year olds and up is 11.3. The average for race records per horse for 2 year olds is 3.5 and for 3 year olds and up is 6.7. This average for horses raced per year for 2 year olds is 1,164 and 4,240 for 3 year olds and up. Horses raced per sire averaged over years was 4.6 for 2 year olds and 10.5 for the older ages. The linear regression of seconds per 100 m fit the average seconds reported for the several distances run almost perfectly with R(2) values greater than .99 for all horse ages on either turf or dirt. There is selection practiced as indicated by horse numbers registered and their numbers over ages for stallions and mares. Less than .2% of the horses raced are geldings. A high degree of control exists by JRA in horse stabling and distribution of racing by horses over racecourses. Jockeys are trained by JRA, ride at several race courses, and ride for many trainers. ZUSAMMENFASSUNG: Genetik der Rennleistung beim Japanischen Vollblut: I. Beschreibung der Daten Die "Japan Racing Association" (JRA) betreibt in ganz Japan zehn Pferderennbahnen sowohl mit Rasen- als auch mit Sandkursen. JRA legt die Regeln für Pferderennen fest, registriert die Eigentümer, Farben und Pferde mittels Fohlenregistrierung und vergibt die Lizenzen für alle JRA-Trainer und -Jockeys. Im Jahre 1990 verzeichneten die zehn Pferderennbahnen 288 Renntage, 3353 Rennen mit 38 397 Pferden; Pferdezucht ist an sieben Orten konzentriert, wobei 93% der Vollblutfohlen aus Hokkaido stammen. Bei 92% der veranstalteten Rennen handelt es sich um Nichthindernisrennen von Vollblutpferden. Dabei stehen die Zweij?hrigen im Wettbewerb, und fast 40% der Rennen gehen über 1200 m. Etwa 39% der Dreij?hrigen nehmen an Rennen über 1800 m teil. Bei den Dreij?hrigen (und Vierj?hrigen) liegen die Distanzen zwischen 1000 bis 3600 m. Der Durchschnitt der Zahl der Rennmeldungen über mehrere Jahre für die Zweij?hrigen betr?gt 10,0 und für die dreij?hrigen und ?lteren Pferde 11,3. Der Durchschnitt der Rennmeldungen pro Pferd bei den Zweij?hrigen betr?gt 3,5 und den dreij?hrigen und ?lteren Pferden 6,7. Durchschnittlich nehmen j?hrlich an Rennen 1164 zweij?hrige und 4240 dreij?hrige und ?ltere Pferde teil. Die durchschnittliche Zahl der Pferde über mehrere Jahre war 4,6 pro Vatertier für die Zweij?hrigen und 10,5 für ?ltere Pferde. Die lineare Regression von Sekunden pro 100 m pa?te sich mit R(2) -Werten über 0,99 fast genau den Durchschnittssekunden an, die für die verschiedenen Renndistanzen angegeben wurden, für die Pferde aller Altersgruppen sowohl auf Rasen- als auch Sandbahn. Selektion bei Hengsten und Stuten ergibt sich aus Zahl der registrierten Pferde mit verschiedenem Lebensalter. Unter den an Rennen beteiligten Pferden sind weniger als 0,2% Wallache. Bei JRA herrscht ein hoher Grad an Kontrolle in bezug auf St?lle und die Verteilung über die Pferderennbahnen. Die von JRA ausgebildeten Jockeys reiten auf verschiedenen Pferderennbahnen und für mehrere Trainer.     

Biomicroscopy of the tear film: the tear film of the pekingese dog

Polarised light biomicroscopy was used to examine the normal pre-corneal tear film in 21 eyes of 12 pekingese dogs. The purpose of the study was to examine the influence of excessive exophthalmos on the pre-corneal tear film in the dog. The majority of the animals were found to have high levels of ocular surface contamination by particulate material and plaques of viscous mucus. Other abnormalities included surface lipid with an abnormal granular (three dogs) or 'curdled' (two dogs) appearance; excessive thinning of the lipid layer of the tear film; and the presence of dark globular structures in two dogs, which were presumed to be abnormal meibomian lipid. Break up of the tear film was observed in one dog. Grossly, a thread of viscous mucus was frequently observed along the margin of the lower eyelid. It is postulated that this thread forms because of the excessively exophthalmic conformation of the breed, which prevents the normal access of effete mucus and entrapped debris to the lower conjunctival fornix. The combination of the above factors in the pekingese is suggested as the mechanism whereby the tear film has a reduced stability, thus enhancing the risk from factors more usually considered to initiate corneal ulceration in the breed. The possible adverse effects of lid splitting for the mass removal of distichiae in exophthalmic dogs is discussed.     

Diseases of the horse: the centennial of a great book

A 7-year-old Saint Bernard developed muscular weakness 1 year after right forelimb amputation and adjuvant cisplatin chemotherapy for osteogenic sarcoma. Clinical and laboratory findings supported a diagnosis of myasthenia gravis, and the dog had clinical improvement in response to prednisone treatment. Two additional dogs with myasthenia gravis and osteogenic sarcoma were identified by review of the medical records of the University of California Veterinary Medical Teaching Hospital. Findings indicated that myasthenia gravis or other neuromuscular transmission disorders may be associated with muscular weakness in dogs with osteogenic sarcoma.     

Ultrasonic evaluation of the reproductive tract of the mare: Ovaries

Ultrasonography is useful for monitoring the dynamic follicular and luteal changes of equine ovaries, since it permits rapid, visual, non-invasive access to the reproductive tract. A 5 MHz transducer has greater resolving power and is far more suitable for evaluation of ovaries than a 3–3.5 MHz transducer. Follicles as small as 2–3 mm can be seen and the corpus luteum can usually be identified throughout its functional life. In a study involving daily ovarian examinations, there was a pronounced change in shape of the preovulatory follicle from a roughly spherical to a pear-shaped or oblong form in 66% of the ovulatory periods, This change usually occurred on the day preceding ovulation. The occurrence of ovulation was detectable by the disappearance of a large follicle. In addition, the ovulation site on day 0 was characterized by an intense echogenic area in 88% of 32 ovulations. The developing corpus luteum retained the echogenicity for a mean of 2.4 days. In a blind study, the location of the corpus luteum, as determined by ultrasound, agreed with a previous independent determination of the side of ovulation by palpation in 88% of the 40 bred mares on days 0–14. In all of the 12 mares that were in estrus, the location of the corpus luteum could not be ascertained. In another study, the corpus luteum was identified for a mean of 16 days in 14 estrous cycles. One or more days before the corpus luteum became ultrasonically unidentifiable, it developed increased echogenicity in 36% of the mares, indicating greater tissue density. It is concluded that ultrasonic evaluation of the corpus luteum is superior to digital evaluation by rectal palpation. Some of the potential applications of ultrasonic examination of the ovaries include: 1) obtaining important, sometimes definitive, information by a single examination for judging whether a mare has entered the ovulatory season, 2) aiding in estimating the stage of the estrous cycle, 3) detecting double preovulatory-sized follicles which are in close apposition and difficult to discern by palpation, 4) detecting failure of ovulation or anovulatory estrus by the absence of a corpus luteum, 5) differentiating a persistent corpus luteum from anovulatory or anestrous conditions, 6) diagnosing certain pathological conditions such as peri-ovarian cysts and ovarian tumors, and 7) diagnosing anovulatory hemorrhagic follicles.