RESUMEN

Bone fractures in laying hens are both a welfare and an economic concern for the poultry industry. The aim of this study was to use radiographs to quantify fracture incidence in 6 lines of noncommercial high-producing laying hens. A total of 451 hens (n = 71 to 78) were killed at 47 wk (White Leghorn-Black, White Leghorn-Blue) or 65 wk of age [Barred Plymouth Rock (BR), White Leghorn-Burgundy (WL-BUR), Columbian Plymouth Rock, Rhode Island Red (RIR)]. Radiographs were obtained with hens in 2 positions (lateral and ventrodorsal) and were used to identify fractures in the skeleton. Data on scallop-shaped indentations (possibly fractures) of the keel bone were also collected. After radiography, the left wings were removed for analysis of humeri, radii, and ulnae. Data for the 2 age groups were analyzed separately. The overall incidence of hens with at least 1 fracture was 6.6 and 15.7% in the 47- and 65-wk-old hens, respectively. Fracture incidence in 47-wk-old hens was not different between White Leghorn-Black and White Leghorn-Blue lines. Significant line differences were observed in the 65-wk-old hens, with at least 1 fracture found in 29.5% of RIR hens versus 9.5 and 4.2% observed in Columbian Plymouth Rock and WL-BUR lines, respectively. Fracture incidence in BR hens (18.2%) was greater than in WL-BUR hens. Fractures in RIR hens occurred predominantly in the furculum and wing bones, whereas pubic bones were most affected in BR hens. The proportion of hens with scallop-shaped indentations of the keel ranged from 36.1 to 88.2% and differed between lines in both age groups. High egg production did not seem to be associated with bone fragility in these lines. Two of the older lines (RIR and WL-BUR) had similar egg production, number of eggs to 60 wk, and egg shell weights at 4 ages but had a significantly different fracture incidence. The line differences in fracture incidence may have been affected by calcium metabolism, bone structure, and body weight.

Asunto(s)

RESUMEN

1. Line differences in the incidence of the presence of radiodense material in the central cavities of humeri of 6 different lines of laying hens were observed using radiographs. 2. Internal humeral radiodense material was observed in over 60% of hens in two lines and 18% of hens in two other lines measured at 65 weeks of age. There was no difference in the incidence (15, 16%) between the last two lines observed at 47 weeks of age. 3. In the 4 lines studied at 65 weeks of age the presence of radiodense material was associated with increased humerus dry weight and ash weight in two lines, while percentage-ash was reduced in all 4 lines. 4. Results from this and previous studies suggest that humeral medullary bone could be an appreciable source of variability in experimental data collected to assess skeletal health.

Asunto(s)

RESUMEN

Osteocyte apoptosis caused by load-induced microdamage is followed by osteoclastic bone remodeling, and a causal link between apoptosis and repair has been suggested. The objectives of the present study were to use a chick model to examine the incidence of osteocyte apoptosis and the presence of osteoclasts during the first 96 hours following an osteotomy, prior to extensive callus mineralization. Osteotomies were performed on the right radii of 24 chicks at 23-24 days of age. The left radii served as controls. Radii were collected and processed at six time points following surgery (0, 12, 24, 48, 72, and 96 hours). Decalcified bone tissue sections were stained either for apoptosis using a modified TUNEL procedure or for tartrate-resistant acid phosphatase to identify osteoclasts in the intracortical and periosteal envelopes. The percentage of apoptotic osteocytes, as well as osteoclast counts (n/mm or n/mm2) were quantified in four regions (0-1, 1-2, 2-4, and 4-8 mm from the site of the osteotomy; regions 1-4, respectively) in the osteotomized radii and in the same measured areas in the control radii. Data for osteocyte apoptosis and osteoclasts in the control limb were subtracted from the osteotomized limb data to identify differences due to surgical influence. The incidence of osteocyte apoptosis was significantly higher at 12, 24, 48, and 72 hours versus 0 hours following osteotomy, and the response was highest in region 1; however, there was no interaction between time and region. Intracortical osteoclast counts (n/mm2) were elevated after 48 hours, and the response was similar in all regions. The data demonstrate that osteocyte apoptosis occurs within 24 hours in response to an osteotomy and temporally precedes an increase in osteoclast presence. Hence, osteocyte apoptosis may play a role in signaling during the bone healing process.

Asunto(s)

RESUMEN

OBJECTIVE: To compare the thickness, area, and volume of sutured and nonsutured multilayered cartilage grafts in a rabbit population. DESIGN: Autogenous rabbit cartilage grafts were harvested, layered, and placed in the contralateral auricle. Half the grafts were sutured; the other half were nonsutured. Graft thickness, area, and volume were measured before implantation, after 90 days in vivo, and after explantation. RESULTS: The area and volume of the cartilage grafts increased during the 90-day period. Histologically, this was caused by increased fibrous tissue around the cartilage grafts. Minimal cartilage resorption was observed. No differences were noted between sutured and nonsutured grafts. CONCLUSIONS: Autogenous, fresh, uncrushed, layered nonsutured or sutured cartilage grafts are well tolerated. Statistically significant increases in the area and volume of autogenous, fresh, uncrushed, layered cartilage grafts occurred primarily because of fibrous tissue formation at the margins of the layered grafts. Suturing had no effect on the postoperative volume retention of these layered grafts. This information will be helpful to the facial plastic surgeon when using fresh-layered autogenous cartilage grafts during cosmetic or reconstructive procedures. Arch Facial Plast Surg. 2000;2:256-259

Asunto(s)

Asunto(s)

RESUMEN

An experiment was designed to investigate the effects of dietary melatonin (MEL) on the performance and health of broiler chicks. Chicks raised under constant lighting were fed practical broiler diets in mash form containing 0, 20, or 40 ppm MEL from 0 to 3 wk. A fourth treatment (0 ppm MEL: 6h/d; 20 ppm MEL: 18 h/d) was used to mimic a diurnal light:dark cycle. Commercial broiler grower diets without MEL supplementation were fed from 3 to 6 wk of age. A small dose-related decrease was observed in weight gain (0 to 14 d) and feed consumption (0 to 21 d) due to continuous feeding of MEL. Continuously fed MEL also improved feed efficiency in the first 3 wk vs the control (0 ppm). Growth and feed consumption from 0 to 21 d were not affected by the diurnally fed diet when compared with the control treatment. No effects were found for mortality. However, the incidence of sudden death syndrome (SDS) was numerically less for the diurnal (3.56%) and 40 ppm (3.76%) diets from 0 to 42 d than for the control treatment 5.56%. Skeletal disease was generally unaffected, with the exception of the incidence of crooked toes at 42 d (0 ppm MEL: 8.67% vs diurnal: 4.89%). Dietary MEL fed either continuously or in a diurnal pattern had a minor effect on the performance and health of broiler chickens.

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

RESUMEN

We subjected 35 rbcL nucleotide sequences from monocotyledonous taxa to maximum likelihood relative rate tests and estimated relative differences in rates of nucleotide substitution between groups of sequences without relying on knowledge of divergence times between taxa. Rate tests revealed that there is a hierarchy of substitution rate at the rbcL locus within the monocots. Among the taxa analyzed the grasses have the most rapid substitution rate; they are followed in rate by the Orchidales, the Liliales, the Bromeliales, and the Arecales. The overall substitution rate for the rbcL locus of grasses is over 5 times the substitution rate in the rbcL of the palms. The substitution rate at the third codon positions in the rbcL of the grasses is over 8 times the third position rate in the palms. The pattern of rate variation is consistent with the generation-time-effect hypothesis. Heterogenous rates of substitution have important implications for phylogenetic reconstruction.

Asunto(s)

Asunto(s)

RESUMEN

Indirect mirror laryngoscopy is difficult to learn. An anatomic model of the oropharynx and larynx is described here. This model is used to familiarize medical students with the component skills of mirror laryngoscopy. The students progress to competency at mirror laryngoscopy on patients more quickly after initial use of this model.

Asunto(s)

RESUMEN

Que se debe hacer: El aumento de tamano de un ganglio linfatico en un adulto debe considerarse signo de cancer mientras no se demuestre lo contrario....Interrogar al paciente sobre la presencia de sintomas en el tracto aerodigestivo....Si existe duda en el diagnostico, ha fracasado el tratamiento medico o parece estar indicado el tratamiento quirurgico, se debe consultar con un especialista en cirugia de cabeza y cuello....En presencia de masas en la region parotidea deben considerarse tumores de la parotida mientras no se demuestre lo contrario (incluidos los posibles <> del area preauricular y las masas de la region cervical superior proximas al angulo de la mandibula). Lo que no debe hacerse: Realizar biopsia de masas cervicales antes de la evaluacion completa del paciente... Efectuar biopsia de masas cervicales cuando no se dan las condiciones precisas para llevar a cabo el tratamiento definitivo (extirpacion radical de masas cervicales, tiroidectomia, etc)...Retrasar el diagnostico definitivo de una masa cervical

Asunto(s)

RESUMEN

The care of patients with self-inflicted facial gunshot wounds is complex and challenging. The magnitude and self-inflicted nature of the injuries naturally give rise to questions about potential for successful rehabilitation. The surgical care and rehabilitation of ten such patients are described. The initial grotesque disfiguration belies the reasonable chances for functional restoration. Patients in this series who completed reconstruction swallow well enough to maintain body weight, speak understandably, breathe without tracheostomy, and have an appearance sufficiently normal that they can interact socially without embarrassment. Guidelines are proposed for multidisciplinary medical care leading to satisfactory functional, aesthetic, social, and psychiatric rehabilitation.

Asunto(s)

RESUMEN

We report a case of 'matured' lipoblastoma occurring within the parotid gland of a 7-month-old male. This benign fatty tumor is considered to represent localized continuation of fetal fat development into the post-birth period. At least 7 cases have been reported in the head and neck region, but this is the first known occurrence within a salivary gland.

Asunto(s)

Asunto(s)

RESUMEN

Tumoral calcinosis manifests soft-tissue calcification, usually near major joints. It variably includes hyperphosphatemia, elevated 1,25-dihydroxycalciferol, and an affected sibling. Serum calcium, alkaline phosphatase, and parathyroid hormone are normal. Tumoral calcinosis of the head and neck is very rare, but this diagnosis should be considered when x-ray film of a poorly defined mass shows irregular soft-tissue calcification.

Asunto(s)

RESUMEN

Thirty Holstein cows were fed diets of 50% grain and 50% corn silage (dry matter basis) through the first 18 wk of lactation. Grain mixes were supplemented with inorganic calcium sources (aragonite, calcite flour, or albacar) to provide .6 or .9% dietary calcium (dry matter basis). Phytate phosphorus intake averaged 38.3 and 42.6 g/d in digestion trials conducted during wk 4 and 10 of lactation, respectively. Even though large quantities of feed and significant amounts of grain were consumed, 98% of dietary phytate phosphorus was hydrolyzed to inorganic phosphorus. Neither calcium source nor calcium quantity affected the hydrolysis of phytate phosphorus.

Asunto(s)