Adrenergic and peptidergic innervation of the trachealis muscle in the normal horse: a preliminary report

The tone of respiratory smooth muscle is largely determined by the input from autonomic nerves. The distribution of adrenergic and selected nonadrenergic, non-cholinergic (NANC) nerves in the normal equine trachealis muscle was investigated using immunohistochemistry. The smooth muscle of the trachealis was found to contain numerous nerves immunoreactive for an enzymatic marker of adrenergic nerves, as well as many nerves immunoreactive for a putative NANC neurotransmitter, peptide histidine isoleucine, a potent bronchodilator. The tissues surrounding the respiratory smooth muscle contained numerous nerves immunoreactive for the neuropeptides substance P and calcitonin gene-related peptide, which can cause marked vasodilation and bronchoconstriction. The complex innervation of the equine trachea should be kept in mind when interpreting the results of physiological experiments.     

Hepatic tyrosine aminotransferase and glucocorticoid abuse in meat cattle

Bertarelli, D., Balbo, A., Carletti, M., Cannizzo, T., Girolami, F., Nebbia, C. Hepatic tyrosine aminotransferase and glucocorticoid abuse in meat cattle. J. vet. Pharmacol. Therap.  35 , 596–603. Besides being extensively applied as therapeutical remedies, glucocorticoids (GCs) – most notably dexamethasone or prednisolone – are also illegally used in livestock for growth‐promoting purposes. This study was designed to assess the suitability of liver tyrosine aminotransferase (TAT), a gluconeogenic enzyme known to be induced by GCs, to act as a reliable candidate biomarker to screen for GC abuse in cattle. Enzyme activity was measured spectrophotometrically in liver cytosols or in cell extracts, and TAT gene expression was determined by real‐time PCR. Compared with untreated veal calves, a notable scatter (20‐fold) and much higher median values (3‐fold) characterized TAT specific activity in liver samples from commercially farmed veal calves. A time‐related increase in both enzyme activity and gene expression was detected in rat hepatoma cell lines treated with dexamethasone concentrations (10^?8 or 10^?9 m ) in the range of those recorded in noncompliant samples from EU official controls. In experimental studies in which finishing bulls were administered GCs at growth‐promoting dosages, however, no such changes were recorded in dexamethasone‐treated animals; a statistically significant rise in liver TAT activity (+95%) only occurred in prednisolone‐treated bulls. Although further research is needed to characterize the GC‐mediated response in cattle liver, TAT does not appear to be a specific and sensitive biomarker of GC abuse in the bovine species.     

Employing a Monte Carlo algorithm in expectation maximization restricted maximum likelihood estimation of the linear mixed model

Multiple‐trait and random regression models have multiplied the number of equations needed for the estimation of variance components. To avoid inversion or decomposition of a large coefficient matrix, we propose estimation of variance components by Monte Carlo expectation maximization restricted maximum likelihood (MC EM REML) for multiple‐trait linear mixed models. Implementation is based on full‐model sampling for calculating the prediction error variances required for EM REML. Performance of the analytical and the MC EM REML algorithm was compared using a simulated and a field data set. For field data, results from both algorithms corresponded well even with one MC sample within an MC EM REML round. The magnitude of the standard errors of estimated prediction error variances depended on the formula used to calculate them and on the MC sample size within an MC EM REML round. Sampling variation in MC EM REML did not impair the convergence behaviour of the solutions compared with analytical EM REML analysis. A convergence criterion that takes into account the sampling variation was developed to monitor convergence for the MC EM REML algorithm. For the field data set, MC EM REML proved far superior to analytical EM REML both in computing time and in memory need.     

Effects of plane of nutrition on slaughtering traits and meat characteristics in Murrah graded male buffalo (Bubalus bubalis) calves in Nepal

An experiment was conducted using 17 male buffalo calves to assess the effects of plane of nutrition on slaughtering traits and meat characteristics. To attain 250 kg body weight (BW), the calves were allocated into three groups: high (H), low‐high (L‐H) and low (L) corresponding to concentrate levels receiving the concentrate at 1.50% of BW, 0.75% of BW until 190 kg BW and 1.50% thereafter, and 0.75% of BW, respectively. The animals had ad libitum access to urea‐treated rice straw. No significant differences of hot carcass weight, dressing percentage and lean fat–bone yields were observed among the treatment groups. The L group had heavier brisket weight and lower percentage of round weight in the hot carcass than the H and L‐H groups (P < 0.05). The H group had heavier hearts than the L group, and the H and L‐H groups had heavier livers and kidneys than the L group (P < 0.05). There was no significant difference of rib eye area, pH and the contents of moisture, crude protein and fat in loin meat among the groups. The findings indicated that the effects of plane of nutrition affected the weight or percentages of some cut yields in the hot carcasses and internal organs.     

Successful reduction of a monozygotic equine twin pregnancy via transabdominal ultrasound‐guided cardiac puncture

In horses, twin pregnancy is pathological and represents a potentially life‐threatening condition to the mare and foal. Twinning occurs in approximately 2% of pregnancies. Of these, the majority of cases are dizygotic twins, resulting from 2 ovulations and monozygotic twins are rare. A 12‐year‐old Quarter Horse mare was presented for breeding management with shipped cooled semen and embryo transfer. Seven days post ovulation, a single late morula/early blastocyst was recovered and transferred immediately to a recipient mare. Thirty‐six days after transfer, transrectal ultrasound examination revealed the presence of 2 embryos. A transcutaneous reduction of one of the fetuses was performed successfully at 128 days of gestation. This report is the first to describe a successful reduction of monozygotic twins by transcutaneous ultrasound‐guided cardiac puncture.     

Venograms for Use in Laminitis Treatment

Venography is a very valuable tool that can be used in the diagnosis and treatment of laminitis. It can be used to assess vascular damage in the hoof before changes in radiographic detail occur. When used at onset, the venogram proves to be most valuable. They can not only give baseline measurements but can also show the level of damage that has already occurred. Initial venograms allow farriers and veterinarians to evaluate what degree of corrective treatment is necessary for the best outcome. In addition, a series of venograms can show the process of pathology as well as recovery. From here, treatment can be altered to accommodate the case.     

Rupture of the Vinculum in Association with Tendon Injury within the Digital Flexor Tendon Sheath in Two Horses

The following report documents an unusual anatomical finding in two cases of aseptic tenosynovitis of the digital flexor tendon sheath. Disruption of the vinculum attachment between the palmar/plantar border of the superficial digital flexor tendon and the adjacent palmar/plantar annular ligament was identified in combination with other tendon pathology within the digital flexor tendon sheath. This tenoscopic finding has not been described previously in the literature.