Fetal maceration and partial retention of fetal bones in 2 mares.

Pregnancy loss after Day 40 in mares usually results in the expulsion (abortion) of the fetus and placental membranes. However, fetal retention within the uterus is also a possible outcome, leading to either fetal mummification or maceration. Fetal maceration is septic decomposition of fetal tissues within the uterus following failure of expulsion. It requires the presence of bacteria and oxygen within the uterus, likely originating from an open cervix, and results in tissue autolysis, leaving only fetal bones remaining in the mare. Fetal maceration is a rare complication of pregnancy in mares that is usually associated with a recent history of abortion, a persistent vaginal discharge, and retention of numerous fetal bones. Here, we report 2 cases of fetal maceration with retention of only a few fetal bones in mares that were presented without noticeable clinical signs. Key clinical message: The unusual presentation of fetal maceration in these mares (only a few fetal bones and no noticeable clinical signs) brings attention to the potential insidious nature of fetal retention. It highlights the importance of a thorough reproductive examination before breeding, along with careful and ongoing monitoring after breeding and throughout pregnancy.

Macération fœtale et rétention partielle d'os fœtaux chez 2 juments. L'interruption de gestation après le Jour 40 chez les juments résulte généralement par l'expulsion (avortement) du fœtus et des membranes fœtales. Toutefois, une rétention fœtale dans l'utérus est également un résultat possible, entraînant soit une momification ou une macération fœtale. La macération fœtale est la décomposition septique des tissus fœtaux à l'intérieur de l'utérus à la suite d'un échec d'expulsion. Elle nécessite la présence de bactéries et d'oxygène dans l'utérus, résultant probablement d'une ouverture du cervix, et résulte en une autolyse des tissus, laissant uniquement des os fœtaux à l'intérieur de la jument. La macération fœtale est une complication rare de la gestation chez les juments qui est généralement associée avec une histoire récente d'avortement, une décharge vaginale persistante, et la rétention de nombreux os fœtaux. Nous rapportons ici 2 cas de macération fœtale avec rétention de seulement quelques os chez des juments présentées avec aucun signe clinique notable.Message clinique clé :La présentation inhabituelle de macération fœtale chez ces juments (uniquement quelques os fœtaux et aucun signe clinque notable) met en lumière la nature potentiellement insidieuse de la rétention fœtale. Elle souligne l'importance d'un examen reproducteur complet avant l'accouplement, avec un suivi minutieux et continu après l'accouplement et durant toute la gestation.(Traduit par Dr Serge Messier).

Intra- and inter-rater agreement for the detection of band neutrophils and toxic change in horses.

BACKGROUND: The detection of band neutrophils and toxic change via microscopic blood smear review is vitally important, as their presence indicates systemic inflammation. However, in-clinic evaluation of WBC morphology is often limited. OBJECTIVE: We aimed to determine the agreement between expert raters in the detection of bands and toxic change. METHODS: Three board-certified clinical pathologists each evaluated 109 blood smears from horses with acute disease, and 19 control smears from healthy horses. The pathologists determined if bands were present, and if so, the percentage of bands present. They also determined if toxic change was present, and if so, the grade of toxic change. Intra-rater agreement was evaluated using 12 duplicate blood smears. Agreement on the presence of bands between pathologists and an in-clinic hematology analyzer was evaluated. RESULTS: Intra-rater agreement was substantial to almost perfect. Agreement between pathologists for the detection of bands was moderate, but when pathologists agreed bands were present, there was excellent agreement on the percentage of bands and mature neutrophils. Agreement between pathologists for the detection of high-grade, clinically relevant toxic change was fair. When pathologists agreed high-grade toxic change was present, there was fair agreement on Döhle bodies and cytoplasmic basophilia and poor agreement on cytoplasmic vacuolation. Agreement between individual pathologists and the in-clinic hematology analyzer for the indication of bands was fair to moderate. CONCLUSIONS: Consistent identification of bands and toxic change is challenging, even for highly trained personnel. It is, thus,not surprising that in-clinic blood smear evaluation of WBC morphology by non-experts could be inadequate.

Do plasma protein:fibrinogen ratios in horses provide additional information compared with fibrinogen concentration alone?

The plasma protein:fibrinogen (PP:F) ratio was introduced to aid interpretation of hyperfibrinogenemia by accounting for dehydration. However, this ratio is inconsistently assessed in practice and its clinical value remains unknown. Our objective was to determine whether the PP:F ratio provides additional information in adult horses beyond fibrinogen concentration alone. Two databases were reviewed to identify 412 hyperfibrinogenemic horses. Plasma protein:fibrinogen ratios were calculated and their interpretation compared to the fibrinogen concentration. Ratios < 15 were supportive of inflammation. Albumin and total protein concentrations were evaluated when ratios were ≥ 15 to determine if inflammation was supported. Very good agreement (86%) was found on the presence of inflammation when PP:F ratios were compared to fibrinogen concentration. In 72% of cases in which PP:F ratios did not support inflammation, inflammation was considered likely based on albumin and total protein. These findings suggest that PP:F ratios do not provide additional information in horses over fibrinogen concentrations alone.

Est-ce que le ratio plasma protéine:fibrinogène chez les chevaux amène une information additionnelle par rapport à la seule concentration en fibrinogène? Le ratio plasma protéine: fibrinogène (PP:F) a été introduit pour aider à l'interprétation de l'hyperfibrinogénémie lors d'hémoconcentration. Toutefois, la valeur clinique de ce ratio est inconnue. Notre objectif était de déterminer si le ratio amène une information additionnelle comparé au fibrinogène. Deux bases de données ont été revues pour identifier 412 chevaux hyperfibrinogénémiques. Le ratio a été calculé et son interprétation comparée à celle du fibrinogène. Les ratios < 15 suggèrent l'inflammation. Pour les cas présentant un ratio ≥ 15, la concentration en albumine et protéines totales a été revue pour voir si l'inflammation était possible. Nos résultats indiquent que dans 86 % des cas, le ratio et le fibrinogène suggèrent la présence d'inflammation. Pour 72 % des cas où le ratio ne suggère pas l'inflammation, cette dernière est considérée probable étant donné la concentration en protéines totales et albumine. Ces résultats suggèrent que le ratio PP:F n'apporte pas d'information supplémentaire comparé au fibrinogène.(Traduit par les auteurs).

High intensity, short duration pulling in heavy horses: physiological effects of competition and rapid weight change.

BACKGROUND: The Heavy Horse Pull is a competition where teams of two horses pull an increasingly heavy sled for a short distance. Similar to human wrestlers, some horses may undergo rapid weight change in order to enter a lower weight category. The objectives were to study the physiological effects of this practice as well as of the pulling competition in draft horses. RESULTS: Fifty horses were divided into light-, middle- and heavyweight categories based on their arrival weights and competed 1-3 days after. Body weight was measured upon arrival and pre-competition. Blood was sampled for chemistry and high sensitivity cardiac troponin T (hscTnT) at arrival, pre- and post-competition in 34, 26 and 20 horses, respectively. Body weight increased significantly between arrival and pre-competition for light (7.2% (Median: 62.8Kg (41.7-77.0)) and middle (8.6% (Median: 80.5Kg (62.7-90.9)) weight categories. Change in body weight was correlated (r = 0.69, p = 0.002) with competition ranking for middleweights. The ratios of weight pulled to team body weight were 2.7 (1.9-2.8), 2.6 (2.5-2.6) and 2.4 (2.2-2.5) for the lightweights, middleweights and heavyweights, respectively. Blood chemistry indicated hemoconcentration on arrival in the middleweight and lightweight horses. Hemoconcentration was not seen on arrival in some horses with marked rapid weight change. Overall, no chemistry parameter changed between pre- and post-competition. The hscTnT stayed within normal range post-competition. CONCLUSIONS: While horses arrived to the event with indications of hemoconcentration, they appeared to have sufficient time to rehydrate prior to competition, and the effects of the competition were reversible within 3 h.

Evaluation of coagulation via thromboelastography in healthy horses administered dexamethasone.

Dexamethasone was administered to healthy horses daily for 7 days. Blood samples were collected at 3 time points from both treatment and non-treatment groups, and analyzed via thromboelastography (TEG). There were no significant differences in TEG parameters between treated and untreated horses, or within treatment groups over time.

Évaluation de la coagulation par une thrombo-élastographie chez des chevaux en santé ayant reçu de de la dexaméthasone. La dexaméthasone a été administrée à des chevaux en santé pendant 7 jours. Des échantillons de sang ont été prélevés à trois moments auprès des groupes de traitement et des groupes sans traitement et ensuite analysés par thrombo-élastographie (TEG). Il n'y avait aucune différence significative dans le temps pour les paramètres TEG entre les chevaux traités et non traités ou à l'intérieur des groupes de traitement.(Traduit par Isabelle Vallières).

Pyruvate kinase deficiency confers susceptibility to Salmonella typhimurium infection in mice.

The mouse response to acute Salmonella typhimurium infection is complex, and it is under the influence of several genes, as well as environmental factors. In a previous study, we identified two novel Salmonella susceptibility loci, Ity4 and Ity5, in a (AcB61 x 129S6)F2 cross. The peak logarithm of odds score associated with Ity4 maps to the region of the liver and red blood cell (RBC)-specific pyruvate kinase (Pklr) gene, which was previously shown to be mutated in AcB61. During Plasmodium chabaudi infection, the Pklr mutation protects the mice against this parasite, as indicated by improved survival and lower peak parasitemia. Given that RBC defects have previously been associated with resistance to malaria and susceptibility to Salmonella, we hypothesized that Pklr is the gene underlying Ity4 and that it confers susceptibility to acute S. typhimurium infection in mice. Using a fine mapping approach combined with complementation studies, comparative studies, and functional analysis, we show that Pklr is the gene underlying Ity4 and that it confers susceptibility to acute S. typhimurium infection in mice through its effect on the RBC turnover and iron metabolism.

Efficacy of Saccharomyces boulardii for treatment of horses with acute enterocolitis.

OBJECTIVE: To evaluate the viability of Saccharomyces boulardii after PO administration in clinically normal horses and its efficacy as a treatment for horses with acute enterocolitis. DESIGN: Prospective study. ANIMALS: 5 clinically normal horses and 14 horses with acute enterocolitis. PROCEDURE: Feces were collected from 5 clinically normal horses and submitted for microbial culture for 2 days prior to administration of a lyophilized form of S. boulardii (25 or 50 g, PO, q 12 h) for 10 days. Feces were collected for microbial culture 5 and 10 days after treament initiation and 10 days after treatment was discontinued. Fourteen horses with acute enterocolitis were randomly allocated to receive a placebo or S. boulardii (25 g), PO, every 12 hours for 14 days. RESULTS: S. boulardii was not detected in feces of clinically normal horses. After administration, yeast survived within the gastroinestinal tract but did not permanently colonize it. In horses with acute enterocolitis, the severity and duration of gastrointestinal tract disease during hospitalization were significantly decreased in horses receiving S. boulardii, compared with horses receiving the placebo. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of S. boulardii may help decrease the severity and duration of clinical signs in horses with acute enterocolitis.

Sepsis in adults and foals.

Sepsis develops in horses when the host response to the invading pathogens is not properly balanced according to the severity of the insult. Several clinical conditions frequently encountered in equine practice may be associated with the development of sepsis and have the potential to progress to more severe forms, such as severe sepsis, MODS, and septic shock. Consequently, it is important for equine practitioners to be aware of the manifestations,pathophysiology, and treatment of sepsis. Although enormous progress has been made in recent years in our understanding of the pathophysiology of sepsis. more work remains to be done in improving basic critical care guidelines and basic monitoring in equine intensive care units and in critically evaluating potential equine sepsis therapy. Fortunately, we can learn from the important advances made recently in the treatment of human sepsis patients;hence, rapid progress may be expected in a near future, especially as more and more veterinarians show interest in the discipline of equine critical care. With the completion of several genome projects and the availability of high-throughput genetic techniques, one hopes that we will further refine our understanding of the events underlying the development of severe sepsis and septic shock, which could lead to more appropriate therapeutic intervention targeted to each individual according to the state of the immune response in that horse.

Tools for the diagnosis of equine respiratory disorders.

Respiratory disorders are among the most common problems leading horse owners to seek veterinary attention. Accurate diagnosis of these conditions allows for proper treatment to be instituted, much to the benefit of the patient and satisfaction of the client. As an introduction to this issue on equine respiratory disorders, we review some of the tools that are available to equine veterinarians for the diagnosis of respiratory disorders. Physical and endoscopic examination, radiology, diagnostic ultrasound, techniques for sampling the respiratory tract, hematology, blood gas analysis, respiratory mechanics, and some modern diagnostic tools are briefly covered.