Multicenter, randomized controlled trial of pain-related behaviors following routine neutering in dogs

OBJECTIVE: To evaluate the degree of postoperative pain in dogs undergoing elective castration or ovariohysterectomy (OHE); determine whether an association exists between surgeon experience, incision length, or surgery duration and degree of postoperative pain; and determine whether analgesic treatment decreases expression of postoperative pain behaviors. DESIGN: Randomized controlled clinical trial. ANIMALS: 426 client-owned dogs undergoing OHE or castration. PROCEDURES: Dogs underwent OHE or castration performed by an experienced veterinarian or a fourth-year veterinary student. Dogs were randomly assigned to 1 of 4 treatment groups: no perioperative analgesic treatment (n = 44), preoperative administration of morphine (144), preoperative administration of nalbuphine (119), and postoperative administration of ketoprofen (119). Dogs were evaluated while in the hospital before anesthesia and for 4 hours after surgery and once a day at home for 3 days after surgery. RESULTS: Dogs in all 4 groups had significant increases in overall pain scores after surgery, compared with baseline scores. There were significant differences among groups, with control dogs having significantly higher increases in overall pain scores than dogs in the other groups. Factors that did not influence the frequency or severity of pain-related behaviors included breed, individual hospital, anesthetic induction protocol, surgeon experience, and duration of surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that dogs expressed behaviors suggestive of pain following OHE and castration, that analgesic treatment mitigated the expression of pain-related behaviors, and that surgeon experience and surgery duration did not have any effect on expression of pain-related behaviors.     

Prevalence of cryptosporidiosis in dairy cattle,cattle-keeping families,their non-cattle-keeping neighbours and HIV-positive individuals in Dagoretti Division,Nairobi, Kenya

The breeding of wild animals for commercial purposes is becoming more frequent nowadays. This situation has led to an increase in contact rates between wild and domestic animals, with subsequent reciprocal transmission of parasites. In this study, we characterized the gastrointestinal and blood parasites of a group of 15 semi-captive guanacos (Lama guanicoe). We characterized gastrointestinal parasites by analyzing fecal samples through the sedimentation–flotation technique and hemoparasites by using blood smears stained with Giemsa. We found several gastrointestinal parasites including Nematoda and protozoans. The most frequently found parasites were Nematodirus sp. and Eimeria sp. In contrast with previous studies, neither Cestoda nor Fasciola were found. The only hemoparasite detected was Mycoplasma haemolamae, a parasite already described in llamas and alpacas. We conclude that the most frequent gastrointestinal parasites of semi-captive guanacos were nematodes and protozoans. Also, the hemoparasite M. haemolamae seems to be prevalent among captive populations of South American camelids. Finally, captive guanacos share several parasites with the traditional livestock. Therefore, keeping captive or semi-captive guanacos without an adequate sanitary protocol might have adverse consequences to adjacent traditional cattle farming and/or for wild animals.     

Copper oxide needles administered during early pregnancy improves the copper status of ewes and their lambs

AIM: To determine the effect of copper oxide (CuO) needles administered orally to ewes in early pregnancy on the copper (Cu) status of ewes throughout gestation and lactation, and of their lambs from birth to weaning. METHODS: In mid-April, after mating, 12 twin-bearing ewes were given an oral capsule containing 5 g CuO needles while 12 others served as untreated controls. Changes in Cu status were monitored by determining serum and liver Cu concentrations on Days 1, 62, 117, 153, 185 and 216 in the ewes, and at 1, 36, 68 and 99 days of age for lambs. Pasture herbage samples were collected at about 60-day intervals for Cu, molybdenum (Mo), iron (Fe) and sulphur (S) determinations. RESULTS: Copper status of the ewe flock was adequate, as initial mean serum and liver Cu concentrations were 15 micromol/L and 1,060 micromol/kg fresh tissue, respectively. The CuO needles did not affect serum Cu concentrations of the ewes or their lambs. Mean serum Cu concentration of all lambs at birth was about half that of ewes (8 vs 17 micromol/L), regardless of Cu supplementation, and not until at least 68 days of age was it similar to the dams'. Liver Cu concentrations of lambs at birth were also lower than that of the ewes (380 vs 640 micromol/kg fresh tissue among the controls), but changed little over time. CuO treatment increased liver Cu concentration in ewes for at least 185 days and in lambs for 36 days (p<0.05). Among untreated ewes, there was a seasonal decline in mean liver Cu concentrations, which were highest in autumn and lowest in early spring (1,060 vs 370 micromol/kg fresh tissue). The mean pasture mineral concentrations were Cu 5.7, Mo 0.48, Fe 194 and S 2,900 mg/kg dry matter (DM). CONCLUSIONS: CuO needles administered to ewes in early pregnancy increased their Cu status through gestation and early lactation, and the Cu status of their lambs for 36 days from birth. Serum Cu concentration was not affected by treatment but a marked rise was observed in all lambs between birth and 10 weeks of age. CLINICAL RELEVANCE: Copper deficiency in young lambs may be conveniently and effectively prevented by treating ewes with CuO needles during early pregnancy. The serum Cu concentration in lambs <8 weeks old may not reflect the Cu status of the flock.     

The multiple burdens of zoonotic disease and an ecohealth approach to their assessment

Individual interviews were conducted in 137 households using semi-structured questionnaires to determine the influence of socioeconomic factors on production constraints faced by indigenous chicken producers in the rural areas of South Africa. The major constraints to village chicken production were mortality (95 % of the households) followed by feed shortage (85 %) and low chicken sales (72 %). The logistic regression model showed that households that owned imported/crossbred chickens practiced extensive production system without housing structures and did not have vaccines were more likely to experience high levels of chicken mortality. Poor and youth-headed households with no supplements and vaccines had high probability of Newcastle disease. The probability of a household to experience chicken feed shortage was lower in households that owned indigenous chickens than those that owned imported/crossbred chickens (odds ratio, 11.68; 95 % confidence interval, 1.19–27.44). Youth-headed households that had small flocks and no access to veterinary services were not likely to sell chickens. It was concluded that gender, age, wealth status, production system, chicken flock size, type of chicken breed owned, accessibility of veterinary services, availability of supplements, vaccines and shelter influence village chicken farmer’s production constraints such as feed availability, chicken mortality, prevalence of diseases and chicken sales.     

Musculoskeletal responses of 2-year-old Thoroughbred horses to early training. 1. Study design, and clinical, nutritional, radiological and histological observations

AIMS: This is the first in a series of papers reporting studies in 2-year-old Thoroughbred racehorses that aimed to determine the response of musculoskeletal tissues to early training on grass and sand racetracks. In this paper, the experimental set-up of the whole study is described, and nutritional, workload, and clinical, radiographic and pathological outcomes are reported, including semi-quantitative assessment of macroscopic changes in articular cartilage. METHODS: The study group comprised 14 two-year-old Thoroughbred fillies reared entirely at pasture. Of these, seven were selected by a licensed racehorse trainer to undergo a 4-week period of initial training in which they were taught to accept saddle and rider, followed by a 13-week period of flatrace training at a racetrack (Weeks 1-13); the other seven fillies were confined to large grass enclosures and were not trained. Nutrient, including macro- and trace-element intakes were estimated. Distances cantered or galloped and average velocities were quantified for the trained horses. All horses were observed daily, weighed approximately weekly, and underwent a clinical lameness examination at Weeks 5, 9 and 13. Distal forelimbs were radiographed prior to Week 1, during Weeks 7-8, and again at the end of the study, when macroscopic changes in articular cartilage of the proximal surface of the proximal phalanx were also scored after staining with India ink. RESULTS: Dietary intakes met or exceeded recommended requirements for all nutrients except sodium, which was low in the trained horses. Bodyweight increased throughout the study in the untrained horses, and increased until Week 7 and then decreased slightly in the trained horses. Mean velocity data were used to define three stages of the training programme: Stage 1 comprised canter in Weeks 1-4; Stage 2 comprised canter in Weeks 5-8; and Stage 3 comprised canter in Weeks 9-13 and galloping twice weekly. Four of seven horses completed training. These covered a mean distance of 179.2 km at mean velocities (excluding gallops) of 7.63 m/sec (SD 0.58), 8.99 m/sec (SD 0.56), and 8.43 m/sec (SD 0.74) for Stages 1-3, respectively, and galloped 4.45 km at 14.4 (SD 0.1) m/sec. The three horses that did not complete training became lame in Weeks 9, 10 and 11, and covered 147.9 km at velocities of 7.38 m/sec (SD 0.44), 8.88 m/sec (SD 0.33) and 8.43 m/sec (SD 0.59) and galloped 2.1 km. Overall, slight or intermittent lameness in trained horses was noted on 76/655 (12%) of horse observation days. Swelling was evident on 284/655 (41%) of horse observation days in the metacarpophalangeal (MCPJ) and metatarsophalangeal (MTPJ) joints (92%), palmar metacarpal tendon region (7%) or carpus (1%). Swelling of the MCPJ or MTPJ was not associated with obvious lameness. Radiographic changes were minor and no gross lesions in bone or tendon tissue were evident except for one case of dorsal metacarpal disease. Post mortem, the cartilage of some MCPJ and MTPJ had obvious wear lines and high lesion scores, which were not consistently related to clinical evidence of pain, lameness or joint swelling. Mean lesion scores were not significantly different between the MCPJ and MTPJ, or between trained and untrained horses. CONCLUSIONS: Workload can be readily quantified in racehorses under semi-commercial training conditions. Obvious lesions in cartilage of the MCPJ or MTPJ were present in some trained and some untrained horses and not consistently associated with clinical evidence of lameness, joint swelling or change in other connective tissues. CLINICAL RELEVANCE: Workload data in racing horses are likely to be highly relevant for studying the pathogenesis of changes in bone, tendon and cartilage during training, for training management and for risk analysis in racehorse populations. Although obvious cartilage lesions produced little clinical effect, such lesions have previously been shown to be progressive and to prejudice athletic capability. Detection of such occult lesions in young horses will require more sophisticated detection methods.     

Biomechanical and hydraulic determinants of tree structure in Scots pine: anatomical characteristics

The development of anatomical, hydraulic and biomechanical properties in Scots pine (Pinus sylvestris L.) stems aged 7 to 59 years was followed. The hydraulic diameter and length of tracheids increased with age to a maximum at 15 and 35 years, respectively. Number of tracheids per unit of sapwood area decreased with age to a minimum of 500-600 tracheids mm(-2). Variations in specific hydraulic conductivity and Young's modulus of stems were associated with variation in anatomical properties. Over the time sequence considered, hydraulic and mechanical properties were positively related to each other and followed a similar developmental pattern, with no suggestion of a trade-off between the two. For most of the tree's life-cycle, heartwood made only a small contribution to whole-section mechanical stiffness because of its location close to the flexural neutral axis, and because of the presence of juvenile wood.     

Ultrasound emission after cycles of water stress in Picea abies

The relationships among rate of ultrasound acoustic emission (AE), xylem water potential and transpiration rate were investigated in 5-year-old potted saplings of Picea abies Karst. after cycles of water stress. Water-stressed plants displayed minimum xylem water potentials of -3.9 MPa, near-zero transpiration rates and up to 45 AE counts per minute. After rewatering, water-stressed plants no longer produced AEs. Well-watered control plants produced only a small number of ultrasonic AEs. After three cycles of water stress (lasting 24 days in total), it was estimated that about two-thirds of the functional tracheids were embolized. The concomitant reduction in hydraulic conductance was about 70%.     

Land-use changes alter CO2 flux patterns of a tall-grass Andropogon field and a savanna-woodland continuum in the Orinoco lowlands

Land use changes in the savannas of the Orinoco lowlands have resulted in a mosaic of vegetation. To elucidate how these changes have affected carbon exchanges with the atmosphere, we measured CO2 fluxes by eddy covariance and soil CO2 efflux systems along a disturbance gradient beginning with a cultivated tall-grass Andropogon field (S1) and extending over three savanna sites with increasing woody cover growing above native herbaceous vegetation. The savanna sites included a herbaceous savanna (S2), a tree savanna (S3) and a woodland savanna (S4). During the wet season, maximum diurnal net ecosystem exchange (NEE) over the S1-S4 sites was 6.6-9.3, 6.6-7.9, 10.6-11.3 and 9.3-10.6 micromol m(-2) s(-1), respectively. The rate of CO2 uptake over S1 was lower than that for C4 grasses elsewhere because of pasture degradation. Soil respiration and temperature were exponentially related when soil water content (theta) was above 0.083 m(3) m(-3); however, soil respiration declined markedly as theta decreased from 0.083-0.090 to 0.033-0.056 m(3) m(-3). There were bursts of CO2 emission when dry soils were rewetted by rainfall. During the wet season, all sites constituted carbon sinks with maximum net daily ecosystem production (NEP) of 2.1, 1.7, 2.1 and 2.1 g C m(-2) day(-1), respectively. During the dry season, the savanna sites (S2-S4) became carbon sources with maximum emission fluxes of -0.5, -1.4 and -1.6 g C m(-2) day(-1), respectively, whereas the tall-grass field (S1) remained a carbon sink with a maximum NEP of 0.3 g C m(-2) day(-1) at the end of the season. For all measurement periods, annual NEP of sites S1-S4 was 366, 6, 116 and 139 g C m(-2), respectively. Comparisons of carbon source/sink dynamics across a wide range of savannas indicate that savanna carbon budgets can change in sign and magnitude. On an annual basis, gross primary production over the S1-S4 stands was 797, 803, 136 and 1230 g C m(-2), respectively. Net primary productivity (NPP) of the S1-S4 stands, calculated from eddy covariance measurements as the daily sum of NEE and day and night heterotrophic respiration was 498, 169, 181 and 402 g C m-2 year-1, respectively. These values were slightly higher than NPP based on harvest measurements (432, 162, 176 and 386 g C m(-2) year(-1), respectively), presumably because fine roots were incompletely harvested. Soil water content limited carbon uptake at all sites, and water-use efficiency (WUE) was related to rainfall dynamics. During the dry season, all sites except the cultivated tall-grass Andropogon field (S1) had a negative WUE. Although our results are specific to the Orinoco vegetational mosaic, the effects of land-use practices on the controls and physiological functions of the studied ecosystems may be generalized to other savannas.