Factors affecting recipients' pregnancy, pregnancy loss, and foaling rates in a commercial equine embryo transfer program

During 11 breeding seasons, 351 7- to 10-day-old horse embryos were nonsurgically transferred into recipients that ovulated between 3 and 10 days earlier. Pregnancy rates at 14 and 40 days and foaling rates were 77.8% (273/351), 69.2% (243/351), and 64.4% (226/351), respectively. Pregnancy loss between 14 and 40 days was 11% and between 40 days and delivery was 7%. The transfer of quality grade 3 to 4 embryos resulted in a significantly lower pregnancy rate at 14 days compared with the transfer of grade 1 to 2 embryos (46.2% vs. 79%; P < .05). Eight-day-old embryos resulted in significantly lower pregnancy losses than day 9 or 10 embryos, as occurred for embryos between 400 and 1200 μm compared with embryos <400 μm. Embryos recovered from mares >20 years resulted in a significantly higher pregnancy loss rate than those recovered from younger mares. The same happened for embryos coming from mares affected by reproductive pathologies compared with healthy mares performing sport activity. None of the evaluated parameters influenced recipients' foaling rate significantly

Retrospective study of factors affecting multiple ovulations, embryo recovery, quality, and diameter in a commercial equine embryo transfer program

In this study, 198 donor mares of different breeds, ages, and reproductive category were inseminated with fresh, cooled and frozen or frozen and cooled semen at the embryo transfer station or in private artificial insemination centers during 10 breeding seasons. The results of this activity were retrospectively analyzed by Pearson Chi-square test and logistic regression to evaluate factors affecting multiple ovulations, embryo recovery, embryo quality, and embryo diameter. Out of the 661 cycles, 937 ovulations were recorded (mean ovulations/cycle: 1.42 ± 0.58). Ovulation rate and incidence of multiple ovulations were significantly affected by age, breed, and reproductive category. Uterine flushings for embryo recovery were performed between 7 and 10 days after ovulation and resulted in the recovery of 338 embryos (51.1% embryos/cycle and 36.1% embryos/ovulation, respectively). At least one embryo was recovered in 298 flushings (45.1%). The factors affecting embryo recovery were age, breed, reproductive category, type of semen, number of ovulations, and location of artificial insemination. Flushing protocol and day of flushing had no effect on embryo recovery. Age, type of semen, number of ovulations, and day of flushing had a significant influence on embryo diameter (N = 215). None of the factors included in the model had an effect on embryo quality distribution

Lacrimal Secretion Variation and Menace Response Appearance in Healthy Standardbred Foals From Birth to Four Weeks of Age

This study assesses lacrimal secretion in healthy foals within 48 hours after birth and evaluates their variations in lacrimal secretion and menace response appearance during the first month of life. A total of 31 Standardbred foals were evaluated. Foals were housed with their dams in 4 × 4 m boxes throughout the study. A complete ophthalmic examination was performed for each animal enrolled in the study, including the foals’ dams which were used as a control group to compare the lacrimal secretion of foals at birth with that of adult horses. In foals, the Schirmer Tear Test I (STT I) and menace response were evaluated within 48 hours after birth (T0) and weekly for a total of four times (T1, T2, T3, and T4). In mares, the STT I was evaluated once, before delivery. The Schirmer Tear Test I results of 11 out of 31 dams were excluded because of signs of ocular adnexa inflammation which might otherwise have influenced lacrimal secretion. At T0 STT I values in foals (19.11 ± 2.49 mm/min) were lower than those of their dams (23.20 ± 1.83 mm/min). In addition, the mean STT I in foals decreased during the study period and reached its nadir at T3 (16.84 ± 2.33 mm/min). None of the foals showed a menace response at any observation point. In conclusion, within 48 hours after birth, healthy Standardbred foals show a lower lacrimal secretion than their dams, and tear secretion does not seem to increase during the first month of life. In this period, poor lacrimation associated with the absence of an evident menace response might be predisposing factors for developing corneal ulcers

Evaluation of a smartphone electrocardiograph in healthy foals and comparison to standard base-apex electrocardiography

Smartphone-based technology for ECG recording has recently spread as a complementary tool for electrocardiographic screening and monitoring in adult horses and in other animal species. The present study aimed to assess the feasibility and accuracy of a smartphone-based ECG in healthy foals. This was a prospective observational study (authorization n. 45,865/2016) including 22 foals aged less than 21 days. A reference standard base-apex ECG (rECG) was acquired, and a smartphone ECG (sECG) was recorded immediately after by using a smartphone-based single lead electrocardiograph. All ECG tracings were evaluated in a blind fashion by a single board-certified cardiologist, who judged whether the tracings were acceptable for interpretation and performed ECG measurements and diagnosis. The Spearman correlation coefficient, the Cohen's k test and the Bland-Altman test were used to assess the agreement between sECG and rECG. All sECG tracings were acceptable for interpretation. All foals showed sinus rhythm on both rRCG and sECG tracings, with perfect agreement in heart rate classification (κ = 0.87; p < 0.001). No clinically relevant differences were found in the assessment of waves and intervals duration. Concerning P wave and QRS complex polarity, the percentage of agreement between rECG and sECG was 78% and 83%, respectively. About ECG tracing quality, rECG and sECG showed a substantial agreement (κ = 0.624; p < 0.001). In conclusion, the smartphone-based ECG device tested in the present study recorded good quality single-lead ECG tracings in foals, reliable for heart rate and ECG measurements, but different polarity of P waves and QRS complexes was found in some foals in comparison to rECG

Peripartum findings and blood gas analysis in newborn foals born after spontaneous or induced parturition

Induction of parturition in horses is still not well accepted due to the potential peripartum complications for mares and newborn foals. We assessed differences after spontaneous and induced parturition with low doses of oxytocin (OX) in 1) incidence of peripartum complications in mares; 2) viability, behavioral, physical, and venous blood gas analyses in foals. In this study 61 mares were included; 45/61 were enrolled in the spontaneous foaling group (SF) and 16/61 in the induced foaling group (IF). In the IF group, when the calcium in mammary secretion reached concentrations of !250 ppm, mares received a single injection of 2.5 IU of oxytocin IV once a day until foaling. Mares’ breed, age, parity, gestational and stage II length, and peripartum complications were recorded. Foal maturity, vital (Apgar score), behavioral and physical parameters were assessed at birth, and the foal clinical condition was monitored for one week. A jugular venous blood sample was collected at birth for blood gas analysis, acid-base status, and lactate assessment. The median gestational length was within the reference interval in all the mares included and did not differ between the two groups. No statistical differences in the II stage length nor in incidence of peri- partum complications were observed between the two groups. All the foals were born alive and showed no signs of prematurity/dysmaturity. No statistical differ- ences were found in foal viability between the two groups. Time to stand and nurse from the mare, and body temperature were significantly higher in the IF compared to the SF group. Venous blood pH, SO2% and BE were lower, while pCO2 and lactate were higher in the IF than in the SF group. All the foals in both groups remained clinically healthy during the observation period. In conclusion, at term induction of parturition with a low dose of oxytocin does not have adverse effects on peripartum in mares. Our findings suggest that at term induced foals suffer slightly greater, but not clinically significant, hypoxia, hypercapnia and acidosis than spontaneously delivered foals

Valutazione dell’utilità del leucogramma, fibrinogenemia ed esame ecografico del torace nella diagnosi precoce della Rodococcosi nel puledro

RIASSUNTO La Rodococcosi è una malattia che colpisce il cavallo ed altri mammiferi compreso l’uomo. Il batterio è un coccobacillo immobile, Gram+, asporigeno, aerobio obbligato, tellurico, coprofilo ed è un patogeno intracellulare facoltativo, con la capacità di vivere nei macrofagi alveolari inibendo la fusione del fagosoma con il lisosoma. Si sviluppa molto velocemente nelle feci equine e i puledri si infettano in particolare per via aerogena quando il batterio è disperso in aerosol. Le manifestazioni cliniche nei puledri che arrivano a sviluppare la polmonite piogranulomatosa sono paucisintomatiche e gli ascessi non sono facilmente rilevabili con la visita fisica, ma ben evidenziabili attraverso l’esame radiografico ed ecografico del torace. Scopo della presente indagine è stato quello di verificare l’attendibilità di alcuni esami di laboratorio e dell’esame ecografico delle pleure nella diagnosi di Rodococcosi del puledro. Lo studio è stato condotto durante le stagioni riproduttive 2004-2005, durante le quali sono stati esaminati 25 puledri tra i 3,5 e i 5,5 mesi. I soggetti sono stati controllati regolarmente con l’esame obiettivo particolare dell’apparato respiratorio e attraverso esame ecografico delle pleure. I 13/25 puledri (52%) che non hanno manifestato alcun sintomo di malattia e sono risultati negativi all’esame ecografico sono stati ritenuti sani e hanno costituito il gruppo di controllo. I puledri sani sono stati sottoposti a prelievi del sangue ogni 15 giorni per un periodo di due mesi (giugno-luglio), per la determinazione di WBC e fibrinogenemia. Il gruppo dei malati (12/25 soggetti pari al 48% degli esaminati) è stato definito tale sulla base dei rilievi clinici, dell’esame immunoistochimico del lavaggio broncoalveolare e sui rilievi ecografici; questi puledri sono stati controllati il giorno della diagnosi, quindi ogni 3 giorni fino alla risoluzione del caso. L’aumento della fibrinogenemia associato a valori nella norma dei WBC è un indice di patologia respiratoria in atto, ma non di Rodococcosi, perchè i soggetti che non hanno presentato rilievi ecografici e sintomatologia caratteristici (ascessi, murmure respiratorio aumentato e rumori crepitanti) sono guariti in seguito a terapia antibiotica aspecifica. Nei puledri con Rodococcosi sono stati osservati aumento dei WBC e della concentrazione della fibrinogenemia, associati a rilievi ecografici caratteristici. In 2/3 soggetti la terapia con eritromicina e rifampicina è risultata efficace, 1/3 è morto. SUMMARY R. Equi infection affects horse, other mammalians and human beings. Rodococcosis in foals causes suppurative broncopneumonia with abscesses, detected by radiography and ultrasonography. R. equi is a soil organism, Gram+, obligate aerobe, fixed, coprophylic, asporigen, facultative intracellular pathogen that persists in macrophages preventing phagosomelysosome fusion. It grows in the manure and the foals became infected by oral and respiratory route transmission. The aim of this work was to verify the usefulness of some laboratory exams and pleural ultrasonography as diagnostic tools of R. equi infection in foals. The study was performed during breeding seasons 2004-2005. Twenty-five foals aged 3,5-5,5 months were examined; 13 foals (52%) were considered healthy and used as control group. Blood samples were obtained every 15 days from each foal to measure WBC and plasma fibrinogen concentration and pleural ultrasound were performed every 15 days. Twelve foals (48%) showed illness (cough, depression, decreased growth, fever, etc.) and were included in the ill group. These foals were examined at the day of diagnosis and every 3 days until the recovery (laboratory exams and pleural ultrasound), 3 of 12 had rodococcosis. In our study, the high value of plasma fibrinogen concentration with normal WBC could be secondary to respiratory disease, but not to R. equi infection. These patients did not showed specific clinical manifestations and ultrasonographic alterations (abscesses, higher respiratory murmur and crackle noises) and they needed only aspecific antibiotic therapy. Marked increase of WBC with moderately increase of plasma fibrinogen concentration might be considered a more diagnostic tool in rodococcosis, because in our study they were associated with specific ultrasonographic and clinical alterations. These foals needed the specific therapy (rifampin associated with erythromycin) for recovery

Equid alphaherpesvirus 1 from Italian horses: evaluation of the variability of the ORF 30, ORF33, ORF34 and ORF68 genes

Equid alphaherpesvirus 1 (EHV-1) is an important pathogen of horses. It is spread worldwide and causes significant economic losses. The ORF33 gene has a conserved region that is often used as target in diagnostic PCR protocols. Single nucleotide point (SNP) mutations in ORF30 are usually used to distinguish between neuropathogenic and non-neuropathogenic genotypes. An ORF68 SNP-based scheme has been used for grouping different isolates. Recently, the highest number of variable sites in EHV-1 from the UK has been found in ORF34. In this study, EHV-1 positive samples from Italian horses with a history of abortion were investigated by amplifying and sequencing the ORF30, ORF33, ORF34 and ORF68 genes. Most animals were infected by the neuropathogenic type A2254G. A 118 bp deletion was found at nucleotide positions 701–818 of the ORF68 gene, making impossible to assign the samples to a known group. Sequencing of the ORF34 gene with a newly designed nested PCR showed new SNPs. Analysis of these sequences and of those obtained from genetic databases allowed the identification of at least 12 groups. These data add depth to the knowledge of EHV-1 genotypes circulating in Italy

BLOOD GAS LEVELS IN NEWBORN FOALS AFTER NORMAL AND ASSISTED DELIVERY

Umbilical cord blood gas analysis can provide important information about conditions of the newborn and its use is common in human medicine for diagnosis of perinatal diseases. The aim of this study was to evaluate the blood gas levels and acid-base status in newborn foals after normal and assisted delivery. Fifteen foals were included and were divided into 2 groups: 12 healthy foals (Group 1) with gestational age ≥320 days, normal delivery, and APGAR score ≥8 five minutes after birth and 3 foals (Group 2) with gestational age ≥320 days, assisted delivery and APGAR score <8. Blood samples were drawn from an umbilical artery (Group 1) and from jugular vein (Group 2). The pH, pCO2, pO2, SO2%, HCO-3 and base excess were assessed using a standard laboratory blood gas analysis. Blood lactate concentration was also evaluated in 6 foals of Group 1 and in all foals of Group 2 with a hand-held analyzer. Mares’ age and parity, gestational age, and length of stage II labor were also recorded. Shapiro-Wilk normality test was applied. Whitney test for unpaired data and Student’s t test were used for statistical analysis. Statistical differences were obtained for pH (Group 1: 7.4±0.1; Group 2: 7.3±0.0), HCO-3 (Group 1: 31.5±6.2 mmol/L; Group 2: 30.1±2.1 mmol/L), lactate (Group 1: 5.4±1.9 mmol/L; Group 2:13.0±8.0 mmol/L), and base excess (Group 1: 5.7±6.2; Group 2: 3.3±1.3), while no differences were obtained for the other data collected. Our results showed acidosis in foals born after assisted delivery, as reported in human neonatology

THE EFFECTS OF UTERINE OZONE INSUFFLATION IN MARES AFFECTED BY ENDOMETRITIS: PRELIMINARY RESULTS

Endometritis represents one of the main causes of subfertility in mares. Recently, alternative therapies such as ozone uterine insufflation have been proposed [1] [2]. The present study aimed to describe uterine ozone (O3) effects on mares affected by endometritis in terms of pregnancy rate (PR), cytological, microbiological, and histopathological findings (altogether: diagnostic procedures = DP). In Study 1, five former embryo recipient mares, aged 10-21 years, were artificially inseminated (AI) for 2 control cycles (N=10) with fresh pooled semen from two fertile stallions and flushed for embryo recovery. In another 2 cycles, the same mares underwent DP and O3 treatment, in the first cycle, and DP, AI, with the same stallions, and uterine flushing for embryo recovery, in the second cycle. In Study 2, five barren commercial mares, aged 16-20 years, underwent DP followed by O3 treatment, in the first cycle, and DP, AI, with different commercial stallions and semen, and pregnancy diagnosis, in the second cycle. In both studies, treatment consisted of intrauterine O3 insufflation (volume: 300 ml; [O3]: 40 μg/ml), for 3 consecutive days. Samples for cytological and microbiological evaluation were collected by uterine lavage with 100 ml of Sterile Ringer Lactate, while samples for histopathology by endometrial biopsy. Fisher exact test was used to compare results pre and post O3 treatment, when indicated. In Study 1, 9/10 cycles (90%) before and 4/5 (80%) after O3 treatment resulted in an embryo recovery (NS), while, in Study 2, 0/5 mares before and 4/5 (80%) after O3 treatment were pregnant at 14 and 60 days (P=0.0476). Considering Study 1 and 2 altogether, only two mares resulted positive at cytological examination pre O3 treatment and both were negative after; only one mare was cultured positive, before and after treatment, and histopathology score improved post O3 treatment in 6/10 mares (NS). In conclusion, intrauterine ozone treatment for equine endometritis, appeared not harmful for fertility and able to improve pregnancy rates in barren mares. Further studies in a larger number of animals are warranted to confirm these results and to better describe the effects of such treatment on uterine quality