Propofol-sparing and hemodynamic effects of guaifenesin in sheep.

OBJECTIVE: To evaluate the propofol-sparing and hemodynamic effects of guaifenesin administered for co-induction of anesthesia in sheep. STUDY DESIGN: Prospective, blinded, two-way crossover experimental study. ANIMALS: Thirteen healthy adult female sheep. METHODS: Anesthesia was induced without premedication with intravenous (IV) guaifenesin 5% at 100 mg kg-1 (GGE) or an equivalent volume of physiologic saline (SAL), followed by IV propofol at a controlled rate (1 mg kg-1 min-1). Heart rate (HR), respiratory rate and oscillometric noninvasive arterial blood pressure (NIBP) were recorded at baseline after co-induction administration, following endotracheal intubation and every 2 minutes thereafter for 10 minutes. Propofol doses required to achieve intubation after each co-induction treatment were compared by independent Student's t-test. Values of p < 0.05 were considered statistically significant. RESULTS: The propofol dose required (mean ± standard deviation) to achieve intubation was significantly lower (p = 0.001) in the GGE treatment (3.40 ± 0.74 mg kg-1) than in the SAL treatment (5.94 ± 1.09 mg kg-1). HR was increased after anesthetic induction compared with baseline in both treatments. HR was generally lower in the GGE treatment than in the SAL treatment. NIBP did not vary between GGE and SAL treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Guaifenesin, when administered as a co-induction agent with propofol in sheep, reduces propofol dose requirements and maintains hemodynamic variables within a clinically acceptable range.

Nerve growth factor-ß effects on post-thaw bull semen quality: Effects of nerve growth factor-ß added to extenders for cryopreservation of electro-ejaculated and epididymal bull semen.

Nerve growth factor-ß (NGF) is a seminal plasma protein associated with improved sperm membrane integrity and motility in mammalian species. The objective of this study was to compare post-thaw semen quality from both ejaculated and pididymal-collected bull sperm incubated with purified NGF prior to cryopreservation. Semen was obtained from Angus × Simmental crossbred bulls (n = 10) collected by electroejaculation, followed by castration and epididymal sperm collections 3 days later. Semen samples were incubated with extender having 0 ng/mL (CONT), 0.5 ng/mL (LOW), 5 ng/mL (MED), or 50 ng/mL (HIGH) of purified NGF prior to cryopreservation. Sperm motility was assessed in each sample prior to treatment and cryopreservation and at post-thaw. Flow cytometry was used for post-thaw assessment of sperm viability (SYBR-14/PI), acrosome integrity (FITC-PNA/PI), and chromatin stability (acridine orange). Values for post-thaw sperm motility and velocity variables were decreased, while linearity was increased in samples of the HIGH compared with CONT group (P < 0.01), but there were no differences in epididymal samples (P> 0.05). Samples from the HIGH group also had a lesser amplitude of lateral head displacement at 2.5 and 3 h post-thaw (P < 0.01). Post-thaw sperm viability, acrosome integrity, and DNA fragmentation index were not affected by NGF treatment in either ejaculated or epididymal sperm (P> 0.05). In conclusion, supplementation of freezing extender with NGF had minimal effects on post-thaw sperm quality in bulls. Results indicate NGF may have a function in preventing premature sperm hyperactivation in ejaculated, but not epididymal-collected spermatozoa. Fertility studies, both in vitro and in vivo, are warranted to ascertain the relevancy of these findings.

Comparative analysis of four commercial on-farm culture methods to identify bacteria associated with clinical mastitis in dairy cattle.

Several multiple-media culture systems have become commercially available for on-farm identification of mastitis-associated pathogens. However, the accuracy of these systems has not been thoroughly and independently validated against microbiological evaluations performed by referral laboratories. Therefore, the purpose of the present study was to evaluate the performance of commercially available culture plates (Accumast, Minnesota Easy System, SSGN and SSGNC Quad plates) to identify pathogens associated with clinical mastitis in dairy cows. Milk samples from the affected quarter with clinical mastitis were aerobically cultured with the on-farm culture systems and by two additional reference laboratories. Agreeing results from both standard laboratories were denoted as the reference standard (RS). Accuracy (Ac), sensitivity (Se), specificity (Sp), positive and negative predictive values (PPV and NPV, respectively) and Cohen's kappa coefficient (k) of on-farm plates were determined based on the RS culture of 211 milk samples. All four plate-systems correctly identified ≥ 84.9% of milk samples with no bacterial growth. Accumast had greater values for all overall predictive factors (Ac, Se, Sp, PPV and NPV) and a substantial agreement (k = 0.79) with RS. The inter-rater agreements of Minnesota, SSGN, and SSGNC with RS were moderate (0.45 ≤ k ≤ 0.55). The effectiveness to categorize bacterial colonies at the genus and species was numerically different amongst the commercial plates. Our findings suggest that Accumast was the most accurate on-farm culture system for identification of mastitis-associated pathogens of the four systems included in the analysis.

Polymorphisms of the Toll-Like Receptor 2 of Goats (Capra hircus) may be Associated with Somatic Cell Count in Milk.

Toll-like receptor 2 (TLR2) plays an important role in recognition by the innate immune system of Gram-positive bacteria. As Gram-positive bacteria cause mastitis, we examined variations in the region of the TLR2 gene that codes for the extracellular domain. Samples of forty goats from a single dairy herd were collected, half with low SCC (≤200,000 cells/mL), and half with higher SCC. Two synonymous single nucleotide polymorphisms (SNPs) were identified: 840G > A and 1083A > G. One nonsynonymous SNP 739G > A was identified. This coded for valine or isoleucine, which have similar physiochemical properties, and was not in a region coding for a known functional domain. Surprisingly, the least square mean SCC of the heterozygous goats (146,220) was significantly lower than the SCC of homozygous GG goats (537,700; p = 0.004), although these two groups were similar in days in milk (p = 0.984), and there was no significant difference by breed (p = 0.941). Because factors other than mastitis can affect SCC and our sample sizes were limited, additional studies are needed to corroborate an association between TLR2 genotype and SCC or mastitis in goats.

Clinical disease associated with epizootic hemorrhagic disease virus in cattle in Illinois.

OBJECTIVE: To describe the clinical manifestation of epizootic hemorrhagic disease virus (EHDV) in cattle during an outbreak in northwestern Illinois in the fall of 2013. DESIGN: Outbreak survey. SAMPLE: 18 EHDV-affected cattle herds. PROCEDURES: Herds with confirmed EHDV-infected cattle were selected for the survey on the basis of having a manager willing to participate. A survey was developed and administered to obtain information regarding the demographics of EHDV-affected herds and the clinical signs and outcomes for EHDV-infected cattle. RESULTS: The managers of 13 beef and 5 dairy herds participated in the survey. The herds contained approximately 1,400 cattle, of which 61 were infected with EHDV and 16 died. Most cattle clinically affected with EHDV were adults, although 1 herd had 6 calves with clinical signs, and EHDV was identified during postmortem testing of 1 of those calves. Clinical signs most commonly observed were oral ulcerations or erosions, anorexia, weight loss, and lameness that typically lasted > 7 days. Of the 18 herds, 17 had wooded areas and 14 had at least 1 pond or marsh on the property. Deer were observed on the property of all farms. The EHDV outbreak in cattle coincided with an EHDV outbreak in deer in the region. CONCLUSIONS AND CLINICAL RELEVANCE: This large-scale outbreak of EHDV in US cattle was unusual because calves were affected. Because there is no way to effectively predict or prevent an EHDV outbreak in cattle, development of a vaccine for use in cattle during an outbreak would be beneficial.

A colon-associated cystic mass occurring in conjunction with cecal dilatation in a Holstein cow.

A 7-year-old Holstein cow was presented for reduced appetite and decreased milk production. Based on physical examination, cecal dilatation was the primary differential diagnosis and was confirmed at surgery. However, in addition to the dilated cecum, 2 large cystic masses were found firmly attached to the proximal loop of the ascending colon.

Masse cystique associée au côlon se produisant conjointement à une dilatation cæcale chez une vache Holstein. Une vache Holstein âgée de 7 ans a été présentée pour une perte d'appétit et une réduction de la production de lait. En se fondant sur l'examen physique, une dilatation cæcale a été le diagnostic différentiel primaire qui a été confirmé à la chirurgie. Cependant, en plus d'un cæcum dilaté, 2 grosses masses cystiques ont été trouvées fermement attachées à l'anse proximale du côlon ascendant.(Traduit par Isabelle Vallières).

Development of a novel diagnostic test for detection of bovine viral diarrhea persistently infected animals using hair.

The purpose of this study was to determine whether manually plucked hairs might serve as an alternative sample for a quantitative real time polymerase chain reaction (qRT-PCR) testing. Twenty three, 1~3 week old, non-bovine viral diarrhea virus (BVDV) vaccinated calves, found to be positive for BVDV by immunohistochemical staining, were selected and hairs were manually plucked from the ear. qRT-PCR was performed on samples consisting of more than 30 hairs (30~100) and whole blood. All 23 animals were positive for the virus by qRT-PCR performed on the whole blood and when samples of more than 30 hairs were assayed. Additionally, qRT-PCR was performed on groups of 10 and 20 hairs harvested from 7 out of 23 immunohistochemical staining-positive calves. When groups of 20 and 10 hairs were tested, 6 and 4 animals, respectively, were positive for the virus.