Phenotypic and genetic trends of patellar luxation in Dutch Flat-Coated Retrievers.

Canine patellar luxation has been described in various dog breeds, with high prevalence especially in smaller dogs. Most dogs suffer from medial displacement of the patella, although in larger dogs lateral displacement is also seen. A sex predisposition has been described for females. Patellar luxation is considered a polygenic, multifactorial disorder. From 1990 to 2007, in total 3834 Flat-Coated Retrievers were screened; 23.6% of those animals were affected with patellar luxation. Lateral displacement of the patella was most common in this breed (61% of cases), whereas medial (31% of cases) and lateral and medial (8% of cases) were less common. Unilateral involvement (51% of cases) was just as often observed as was bilateral involvement (49% of cases). Females were more often affected with patellar luxation (30% of all tested females) than were males (17% of all tested males). The heritability of patellar luxation was 0.17 ± 0.03 in this population, and breeding with one affected parent increased the prevalence of patellar luxation in offspring by 45% compared to that with two unaffected parents. Since the start of the screening program, there was an initial decrease from 28% to 18% in incidence, but this stagnated thereafter. The annual average estimated breeding values followed the same pattern. With approximately one quarter of the Dutch Flat-Coated Retrievers being affected with patellar luxation, this population shows unusually high prevalence compared with reports in other large-breed dogs. The heritability for patellar luxation in this population was moderate (0.17), indicating that environmental factors play a large role in the manifestation of the disorder. A screening program reduced the prevalence of patellar luxation in this breed, but improvement has recently stagnated. Inclusion of breeding values in the screening program could improve its effectiveness.

[The use of analgesic and antiphlogistic agents in small animals (author's transl)]. / De toepassing van analgetica en antiflogistica bij de kleine huisdieren

The metabolism of many analgesic and antiphlogistic agents in dogs and cats differs markedly from that in man or other animals. When the known data on the subject are borne in mind, potentially toxic agents such as acetosal, phenylbutazone, ibuprofen and indomethacin may be used without much risk in various indications. It is pointed out that double-blind studies on the clincal effectiveness in patients unfortunately have not yet become available.

[Avulsion fracture of the tendon of origin of the long extensor muscle of the toe in a horse and a cat]. / Avulsie fractuur van de oorsprongspees van de musculus extensor digitorum longus bij een paard en een kat.

An avulsion fracture of the tendon of origin of the extensor digitorum longus muscle is reported in a horse and a cat. This avulsion fracture was due to injury in both animals. There was a striking similarity of radiographic findings in these animals, with involvement of the lateral trochlear ridge and lateral condyle of the femur. The horse was slaughtered because of a poor prognosis as a riding-horse. Fixation of the avulsed fragment with two Kirschner wires resulted in complete recovery in the cat.

[Regional isolation perfusion with cisplatinum in dogs with osteosarcoma of an extremity]. / Regionale geïsoleerde perfusie met cisplatinum bij honden met osteosarcoom van een extremiteit.

In the treatment of osteosarcoma, it is possible to differentiate between systemic therapy and local regional treatment. Systemic treatment of human patients with osteosarcomas consists in adjuvant chemotherapy. This has considerably improved the prognosis in these cases. The primary object in local regional treatment is to prevent local recurrences and to preserve function. As regards extremities, the aim is to preserve the limbs. In the present investigations, the value of regional chemotherapy by isolated regional perfusion with cis-platinum to dogs is studied. This approach was based on the hypothesis that considerable necrosis of tumours may be produced after perfusion with cis-platinum, thus making extremity-saving surgery possible. Isolated regional perfusion with cis-platinum (30 mg/litre of extremity volume) was performed in nine dogs with osteosarcomas of an extremity. A marked effect on the tumour was detectable on the basis of clinical, radiological and histological parameters. In the opinion of the present authors, regional perfusion with cis-platinum may contribute to extremity-saving treatment of osteosarcomas in dogs and human subjects. However, further studies will be required in order to achieve more adequate quantitation an improvement of local effects. In view of the synergy with cis-platinum, the latter may possibly be attained by the addition of hyperthermia (temperatures above 41.5 degrees C).

Prevalence and genetics of patellar luxation in Kooiker dogs.

The prevalence of patellar luxation (PL) and genetic factors potentially involved in the disorder were investigated in Dutch Kooiker dogs. A cohort of 842 Kooiker dogs, the offspring of 195 sires and 318 dams, was screened for PL from 1994 to 2011. The cohort was included in a pedigree of 1737 Kooiker dogs comprising nine generations. PL was present in 24% of screened dogs, with unilateral and bilateral luxation being observed equally frequently. Medial PL was more common (61%) than lateral PL (32%) or bidirectional PL (7%). The frequency of PL was similar in male and female dogs, with a female:male relative risk of 1.15 (95% confidence interval, CI, 0.90-1.48). The heritability of PL in the screened population was 0.27 ± 0.07. Since the start of the screening programme, the prevalence of PL decreased from 28% to 19%. A genome-wide association study of PL with 48 cases and 42 controls suggested the possible involvement of a region on chromosome 3 (Praw = 1.32 × 10(-)(5), Pgenome = 0.142), but the involvement of this region could not be confirmed in a validation group. Breeding programmes for complex diseases, such as PL, would benefit from combining pedigrees, phenotypes and genotypes, i.e. from genomic selection, as is currently the method of choice for breeding of production animals.

Hyperthermic isolated regional perfusion with cisplatin in the local treatment of spontaneous canine osteosarcoma: assessment of short-term effects.

To increase the effect of cisplatin on locoregional osteosarcoma, the short-term effect of hyperthermic isolated regional perfusion (HIRP) with cisplatin (30 mg/L extremity volume) was studied in 28 dogs with spontaneous osteogenic sarcoma, using clinical, radiological, and histological parameters. Thirty days postoperatively, mortality was 14.3%. Total platinum levels at the start of perfusion were 28.2 +/- 14.3 mg/L. A significant improvement (P < 0.001) in clinical score was observed in the overall group at 6 and 12 weeks after perfusion. The radiological parameter showed a stationary X-ray 2 weeks after perfusion and an improved X-ray 6 weeks after perfusion. Overall histological scores showed a moderate effect according to the Huvos classification. No additional therapeutic effect, according to the three parameters, could be demonstrated by increasing the perfusate temperature by 1 degrees C. HIRP with cisplatin is feasible in the local treatment of spontaneous osteosarcoma in dogs with acceptable locoregional toxicity. However, the histological results were modest, with none of the dogs showing a complete response 6 weeks after perfusion. Therefore, the search for the ideal perfusion agent with substantial contribution to the limb-sparing treatment in human osteosarcoma continues.