Effect of subchondral drilling on repair of partial-thickness cartilage defects of third carpal bones in horses

Arthrotomies of middle carpal joints were done on 13 horses, and a 1-cm partial thickness, round defect was made on the radial facet of both third carpal bones. In one joint, 1-mm diameter 1-cm deep holes were drilled within the defect, and one joint was used as a control. horses were assigned to 2 groups--group 1 (n = 6 horses), 5 drill holes; group 2 (n = 7 horses), 11 drill holes. At 1 and 3 weeks after surgery, differences between joints in synovial fluid total protein values, WBC counts, or results of mucin precipitate tests were not significant (P = 0.005). Physically and radiographically, horses were the same during the 12 initial weeks they were housed in stalls and the 9 weeks they were kept in paddocks. Twenty-one weeks after surgery, horses were euthanatized. Joints with drill holes had a significantly greater area (P less than 0.05) of healthy fibrocartilage new tissue: group 1-33 to 68% new tissue, compared with 0 to 23% new tissue in controls; and group 2-22 to 64% new tissue, compared with 0 to 37% new tissue in controls. Differences between healing of defects with drill holes in groups 1 and 2 were not significant. Thickness of new tissue over drill holes was 33 to 61% of thickness of cartilage adjacent to the defect, and thickness of tissue between drill holes was 11 to 43% (group 1) and 8 to 79% (group 2) of the thickness of cartilage adjacent to the defect.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of fermented garlic powder supplementation on growth performance,nutrient digestibility,blood characteristics and meat quality in growing‐finishing pigs

One hundred pigs (BW = 50.7 ± 1.89 kg) were used to investigate the effects of fermented garlic powder (FGP) in growing‐finishing pigs. Pigs were allotted to one of five treatments, included: (i) NC (basal diet); (ii) PC (NC + 44 mg/kg of Tylosin); (iii) FGP1 (NC + 1 g/kg FGP); (iv) FGP2 (NC + 2 g/kg FGP); and (v) FGP4 (NC + 4 g/kg FGP). Supplemental FGP increased average daily gain (ADG) and gain/feed ratio compared with those fed NC diet throughout the experiment (P < 0.05, linearly). Dietary PC treatment increased the ADG and average daily feed intake during the first 6 weeks (P < 0.05). The inclusion of FGP2 and FGP4 treatments had higher apparent total tract digestibility of dry matter and nitrogen (P < 0.05) than those in the NC treatment. Dietary NC treatment exhibited lower (P < 0.05) lymphocyte count (6 and 12 weeks) and immunoglobulin G (12 weeks) than those in the other treatments. Marbling scores were higher (P < 0.05) in FGP treatment groups than the NC treatments. Pigs fed on FGP2 and FGP4 diets evidenced lower 2‐thiobarbituric acid reactive substances value (P < 0.05) than those in the NC and PC treatments. Collectively, our findings demonstrated that the administration of FGP at a level of 2 or 4 g/kg improved growth performance, nutrient digestibility and meat quality in growing‐finishing pigs.     

Treatment of a metallic foreign body in the cranial cervical region of a horse

Ingestion of foreign bodies is uncommon in horses when compared with indiscriminate grazers such as cattle. This case report describes the diagnosis and treatment of a cervical abscess in a Thoroughbred racehorse thought to be associated with ingestion of wire. Radiographic and ultrasonographic examination provided a diagnosis, and conservative treatment of the lesion with antimicrobials initially allowed the lesion to localise closer to the skin for safer surgical exploration. Intra-operative ultrasonographic imaging facilitated surgical access, removal of the foreign body, and drainage. While surgical treatment is usually necessary to resolve an abscess, initially conservative therapy may help to improve the prognosis by simplifying surgical access and reducing the risk of surgical complications.     

Modelling land use strategies to optimise crop production and protection of ecologically important weed species

There is a need to develop farming systems that enable both a satisfactory level of crop production and suitable environmental conditions for natural species. Wildlife‐friendly cropping techniques, such as a reduced amount of applied herbicide or a lower crop density, might be adopted in order to maintain populations of weed species of biological interest. An alternative might be to adopt an intensive cropping system in a part of the field and spare the other part as set‐aside or field margins, available for the natural development of plant species. The objective of this study was to present a method to compare two strategies for maintaining a desirable level of abundance of a given species of interest in agricultural areas, specifically (i) a strategy based on a wildlife‐friendly cropping system in a large cultivated area and (ii) a strategy based on a more intensive cropping system in a reduced area of cultivation, i.e. with land‐sparing. The principle is to calculate the ratio of crop production obtained with strategy (i) to the production obtained with strategy (ii) for a given target density of natural species. We show that the value of this ratio, and thus the relative performance of the two strategies, depends on the density of the weed species that can be maintained in an uncultivated ecological area. The method is applied in case studies of two plant species with contrasting ecology and conservation goals. The numerical results show that the strategy based on a wildlife‐friendly cropping system is more profitable in most situations.     

Progress in the development of tuberculosis vaccines for cattle and wildlife

Vaccination against bovine tuberculosis is likely to become an important disease control strategy in developing countries, which cannot afford a test and slaughter control programme, or in countries which have a wildlife reservoir of Mycobacterium bovis infection. In the past decade, considerable progress has been made in the development and evaluation of tuberculosis vaccines for cattle and for a range of wildlife maintenance hosts including possums, badgers, deer and African buffaloes. Experimental challenge systems have been established for the different target species and the resulting disease process has mimicked that seen in the field. In cattle, neonatal vaccination with BCG appeared to be more effective than vaccination of 6-month-old calves and in most situations no other vaccine has been shown to be better than BCG. However, prime-boost strategies involving combinations of BCG with a protein or DNA vaccine, to improve on BCG vaccination alone, have produced very encouraging results. Differential diagnostic tests have been developed using mycobacterial antigens that are only present in virulent M. bovis to differentiate between BCG-vaccinated and M. bovis-infected cattle. BCG vaccine has been shown to reduce the spread of tuberculous lesions in a range of wildlife species and a prototype oral bait delivery system has been developed. Prospects for the development of improved vaccines against bovine tuberculosis are promising and vaccination approaches could become very valuable in the control and eradication of bovine tuberculosis.     

The effect of biological isolation and a molt-inducing regimen on the recovery of Mycoplasma gallisepticum from commercial Leghorn hens

Two trials were conducted to determine the effect of induced molt on the reisolation of Mycoplasma gallisepticum (MG) from commercial leghorn hens that had been eyedrop-inoculated with MG at 10 weeks of age. Chickens were maintained in a conventional floored chicken house on dry litter through 100 weeks of age. At age 64 weeks, 4 days (Trial 1), and at 100 weeks (Trial 2), hens were swabbed and cultured for MG and then molted in biological isolation units. Swabs were again taken at the end of each molt. No difference was observed in the number of MG isolations between molted hens and controls that did not undergo molting. However, a significant decrease in MG isolations was observed in both trials from swabs obtained when hens were housed on dry litter floors as compared with swabs taken from the same hens after 18 days (Trial 1) or 21 days (Trial 2) of confinement in isolation units.     

Pharmacokinetics of oral ivabradine in healthy cats

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) analytical method for the measurement of the novel heart rate-lowering drug ivabradine and its major metabolite, S-18982, was cross-validated in the plasma of eight healthy cats. Plasma concentrations were then determined after single and repeated oral administration of ivabradine. Individual plasma concentrations versus time from each cat were used in compartmental analysis using the commercially available software WinNonlin. Both ivabradine and S-18982 reached their maximum concentrations of 103.33 and 3.86 ng/mL within 1 h. Following repeated administration, areas under the plasma concentration-time curves for ivabradine and S-18982 did not significantly increase. Two-compartmental and one-compartmental models with first-order input and elimination provided the best fit to the data for ivabradine and S-18982, respectively. Both models were combined to produce a single 4-compartment model characterizing ivabradine and S-18982 pharmacokinetics. The results of this study indicate that repeated oral doses of ivabradine produced plasma drug concentrations suitable for 12-h dosing intervals in healthy cats. Furthermore, the analytical assay and combined ivabradine/S-18982 model provide tools for further evaluation of ivabradine pharmacokinetics and pharmacodynamics in future studies in cats.     

Conception rates in early postpartum ewes bred naturally or by intrauterine insemination

Ewes were treated with a medroxyprogesterone acetate (MAP) sponge for 8 d followed, at sponge removal, with 500 IU pregnant mare serum gonadotropin (PMSG) at d 30, 40 or 50 (d 0 = lambing) to induce estrus. Dry and lactating ewes were divided into equal numbers at each postpartum day and bred at estrus. Conception rates and number of accessory sperm were determined by flushing the oviducts 3 d after mating and examining the recovered ova. There was no effect (P greater than .05) of lactational status on conception rates. Conception rates increased (P less than .05) from d 30 (10%) to d 40 (45%) and from d 40 to d 50 (80%). There were fewer (P less than .05) ova with accessory sperm (5/26) in d-30 ewes compared with d-40 (10/27) or d-50 (12/24) ewes. In Exp. 2, ewes were assigned to two groups after receiving PMSG on d 30: 1) mated naturally or 2) inseminated during laparotomy near the uterotubal junction (UTJ). Dry and lactating ewes were divided evenly within each of the two treatments. Oviducts were flushed and ova were examined for cleavage. The conception rate was 60% in ewes that were inseminated in the UTJ vs 10% in ewes mated to rams (P less than .05). Lactational status had no effect on results. In conclusion, conception rates in postpartum ewes treated with MAP sponge and PMSG increased from postpartum d 30 to d 50 with natural breeding, and d-30 conception rates were increased over natural mating by insemination into the uterine horn near the UTJ.     

Shedding of lymphoid leukosis virus in chickens following contact exposure and vaccination

Chickens contact-exposed to lymphoid leukosis virus at various ages up to 32 weeks responded with relatively high rates of infection as determined by the presence of neutralizing antibody. Virus shedding as determined by cloacal swab and albumen testing occurred in 7 of 8 groups of such chickens, but the incidence was 10% or less and sporadic. Vaccination of chickens immediately before exposure with a low pathogenicity virus of subgroup A at 8 weeks of age did not eliminate subsequent shedding.