Severity Of Osteochondrosis Research Articles

Prevalence and severity of osteochondrosis of the free thoracic vertebra in three modern broiler strains and the Athens Canadian Random Bred control broiler

ABSTRACTOsteochondrosis (OCD) results from a disturbance of endochondral ossification in articular cartilage and is an important cause of lameness in several animal species, including chickens. OCD lesions in the free thoracic vertebra (FTV) of chickens are essential to the pathogenesis of pathogenic Enterococcus cecorum. The goal of this study was to determine the prevalence of OCD in the FTV among three modern broiler chicken crosses (strains A/A, A/B, and C/C) and Athens Canadian Random Bred (ACRB) chickens, which served as the control group. The effect of sex, age, strain, body weight, and incubation temperature profile on OCD severity for each group was determined. At 2, 4, 6, and 8 weeks of age, the FTV of 10 male and 10 female birds from each strain exposed to either optimal or low-early, high-late incubation temperature profiles were collected and scored histologically for OCD lesion severity. OCD spectrum lesions were detected in >70% of all strain/sex combinations, including the ACRB controls. No association was observed between mean OCD score and broiler strain, incubation temperature profile, sex, age, or body weight. These findings indicate that OCD of the FTV is common in broiler chickens with similar prevalence observed in broilers with modern genetics and the ACRB broilers which represent 1950s broiler genetics. As the parameters examined did not have a statistical correlation with OCD, additional work is needed to understand factors that contribute to development of OCD in chickens.

Osteochondrosis prevalence and severity at 12 and 24 weeks of age in commercial pigs with and without organic-complexed trace mineral supplementation.

Maternal and progeny diets supplemented with 2 sources of trace mineral (TM) were evaluated for effects on the size and severity of osteochondrosis (OC) lesions in progeny produced by 64 Landrace × Large White sows. At breeding, sows were randomly assigned to maternal diets (gestation and lactation) consisting 1 of 2 TM treatments. One treatment consisted of inorganic TM (ITM) with ZnO, MnSO, and CuSO at concentrations to provide 150, 50, and 16.5 mg/kg diet of Zn, Mn, and Cu, respectively. The other treatment consisted of the same ITM concentrations plus an additional 50, 20, and 10 mg/kg diet of Zn, Mn, and Cu, respectively, supplied by a blend of AA-complexed TM (CTM) using Availa Sow. Within maternal dietary treatment groups, selected progeny ( = 280) were fed either ITM- or CTM-supplemented diets. The humerus and femur (1 each) from progeny euthanized at 12 ( = 80) or 24 wk ( = 200) were collected for microscopic (12 wk) or gross (24 wk) assessment of OC lesions. Microscopic OC lesions were present in all pigs at 12 wk. Dietary treatments had limited effects on OC prevalence or severity. A maternal × progeny diet interaction ( = 0.044) revealed femoral OC latens lesions that were approximately twice the size in progeny fed CTM that were produced by sows fed CTM compared with those found in pigs in the other 3 dietary treatment groups. At 24 wk, the sum of gross OC scores at predilection sites of the thoracic (elbow joint) and pelvic (stifle and hock joints) limbs remained similar among treatments, despite greater ( = 0.004) gross OC scores of the medial femoral condyle in progeny from sows fed CTM diets than in progeny from sows fed ITM diets, regardless of progeny diet. Progeny produced by sows fed CTM vs. ITM had increased ADG (0.71 vs. 0.68 ± 0.01 kg/d), regardless of the diet fed to progeny during the growth phases. Covariant analysis using ADG did not alter inferences about maternal or progeny diet effects on OC responses. Although 100% of progeny at 12 wk had histologically apparent OC lesions, only 3 of the 200 pigs examined at 24 wk had gross lesions of sufficient severity to potentially result in clinically apparent disease. Therefore, although some results imply that maternal and progeny CTM diets increased the size (12 wk) and severity (24 wk) of OC in 1 site (the femur), on the whole animal level, no evidence of lameness was noted.

Use of serum biomarkers to predict the development and severity of osteochondrosis lesions in the distal portion of the femur in pigs

To evaluate the use of serum biomarkers of cartilage and bone metabolism to predict the occurrence and severity of osteochondrosis (OC) lesions in the distal portion of the femur in growing swine. 71 gilts. At an abattoir, serum samples for analysis of 10 biomarkers indicative of cartilage and bone metabolism were obtained prior to processing of the pigs. The distal portion of each pig's left femur was directly examined and cut into longitudinal sections to evaluate the number and severity of abnormalities on the external surface, articular cartilage, and growth plate. Each specimen was categorized as with (n = 56) or without (15) OC, and an overall OC severity score was assigned to affected pigs. Logistic and linear regression analyses were performed to predict odds of OC on the basis of biomarker concentrations and predict the severity of OC values in affected pigs, respectively. Compared with values in unaffected pigs, serum concentrations of C-propeptide of type II collagen (CPII) and cartilage oligomeric matrix protein were significantly increased and concentrations of carboxy-terminal telopeptide of type II collagen 3/4-length fragment (C2C) and pyridinoline cross-links were significantly decreased in affected pigs. A 2-fold increase in CPII concentration increased the odds of pigs having OC by a factor of 97 (95% confidence interval, 6 to infinity). Changes in serum C2C concentration accounted for 49% of the variation in overall OC severity score. Assessment of serum biomarker concentrations may be useful in the diagnosis of OC and aid in reduction of lameness in swine herds.

Articular/epiphyseal osteochondrosis in Thoroughbred foals at 5 months of age: Influences of growth of the foal and prenatal copper supplementation of the dam

AIMS: To determine the influence of copper (Cu) supplementation by injection of mares in late gestation on the frequency and severity of osteochondrosis (OC) lesions in their foals at around 160 days of age. To determine if there was any influence of the concentration of Cu in the liver, growth rate, birthweight, weight at 160 days of age, fatness, sex, or year of birth of the foal on the frequency and severity of OC lesions. To determine the influence of dam's age, and sex and birthweight of the foal on the growth rate from birth to 160 days of age, and weight at 160 days of age. METHODS: Thirty-three Thoroughbred foals, born in two consecutive years, were weighed every 2 weeks from birth. The dams had been supplemented with parenteral Cu or saline during late gestation, and the supplementation regimens were different in each year. Foals had liver biopsies harvested at birth for determination of Cu concentration. Pasture samples were collected every 4–8 weeks for analysis of concentration of Cu and zinc (Zn). At 160 days of age, articular cartilage of long bones was examined. Gross lesions were counted and scored, then sawn and radiographed, and processed for histopathology. Lesions were given radiographic scores and histopathological scores. Maximum scores for each lesion were combined to give a total OC score for each joint and each foal. The fatness of 20 foals (10 each from Years 1 and 2) at 160 days of age was determined chemically. RESULTS: Supplementation of dams with Cu had no significant effect on the concentration of Cu in the liver of foals at birth, or on the frequency or severity of lesions in articular cartilage at 160 days of age. The Cu and Zn concentrations of pasture were similar in Years 1 and 2, and were lower than current recommendations. All foals in Year 2, and 9/10 foals in Year 1 had irregularities in cartilage that was confirmed histologically to be indicative of OC. The average number of lesions per foal was 4.7 (SD 1.1) and 5.7 (SD 1.1) in Years 1 and 2, respectively. However, the severity of the lesions was considered mild, and no foals showed any clinical evidence of OC while alive. The number of lesions in the tarsocrural (TC) joint and the TC OC score at 160 days were positively associated with average daily weight gain (ADG) in the previous 4 weeks (p=0.005 and p=0.001, respectively). There was no significant effect of sex, fatness, birth-weight, weight at 160 days of age, or year of birth of the foal on the frequency and severity of OC lesions. CONCLUSIONS: Many of the lesions classified as OC, using classification systems described by other authors, were likely to be normal variations of the process of endochondral ossification. Despite the high frequency of such lesions, they were considered to be of minor significance and none were clinically evident. The distribution of lesions was not typical, and most probably reflected the subtlety of the lesions. These results support the hypothesis that Cu is an over-emphasised factor in the aetiopathogenesis of OC. The relationship between subtle macroscopic lesions and lesions resulting in clinical signs of disease requires further investigation.

Survival of Swedish Landrace and Yorkshire sows in relation to osteochondrosis: a genetic study

AbstractA genetic study was carried out to: (1) conduct a genetic analysis of longevity of Swedish Yorkshire sows, (2) study the environmental and genetic factors that influence the presence and severity of osteochondrosis, and (3) investigate the relationship between breeding values for osteochondrosis and longevity of sows. The data for the longevity analyses were extracted from the Swedish litter-recording scheme data bank (Quality Genetics, former Scan Avel HB). After editing original data, records of 9814 Yorkshire sows with 7553 (77%) uncensored and 2261 (23%) censored born 1986 through 1997 were used in the analyses. Litter size at first and last farrowing, age at first farrowing, backfat thickness, daily gain and weight at completion of performance test (~170 days) were included as fixed effects in all analyses. The combination of herd-year effect was treated as fixed or random, time-independent or time-dependent in different analyses. Sire effect was considered as the source of genetic variation and thus a sire model was used. The analyses of osteochondrosis were based on information on 14 388 Landrace and 14 458 Yorkshire pigs from the Swedish pig progeny-testing scheme, recorded from 1987 through 1997. The birth herd and the combination of sex, testing station, year and month for start of test were included as fixed effects in the statistical model. Variance and covariance components for osteochondrosis recorded at elbow and knee joints were estimated in a bivariate animal model by the restricted maximum likelihood method within each breed. In the survival analyses (Yorkshire sows), the fixed effects of herd-year (when it was treated as fixed effect), litter size at first and at last farrowing, age at first farrowing, backfat and gain at completion of performance test were highly significant (P < 0·01). Herd-year combination was the major cause of variation for risk of culling, compared with other fixed effects. The risk of being culled at a certain time decreased as the litter size at first and at last farrowing, or backfat of the gilt at completion of performance test increased. With increasing age at first farrowing, the risk of being culled at a certain time increased. Heritability in the original scale for longevity ranged from 0·21 to 0·31. The results for osteochondrosis showed that the combined effect of sex-testing station-year and month of start of test was highly significant (P < 0·01). Estimates of heritabilities for osteochondrosis score were similar for both Landrace and Yorkshire breeds and was, on average, 0·21. The correlations between breeding values for longevity and osteochondrosis were low (on average 0·07, adjusted for genetic trends) but were significant (P < 0·01) and in a favourable direction: higher osteochondrosis load associated with higher risk of being culled.

Differentiation of the effects of somatotropin and enhanced growth rate on the occurrence of osteochondrosis in pigs

One hundred and twenty Yorkshire pigs, equal numbers of gilts and barrows, with an initial average weight of 69 kg were used in the present experiment. The animals were treated with 2 mg d−1 of recombinant porcine somatotropin (rpST) either by daily injection or by slow-release implant, while the control animals were treated with a sham implant. The daily injection of rpST increased daily weight gain (P < 0.0001) and decreased feed/gain ratio (P < 0.0001) and daily feed intake (P < 0.0001). Barrows grew faster (P = 0.02) and ate more feed (P = 0.0001) than gilts. On reaching ~ 100 kg, all pigs were slaughtered, and 60 pigs (two from each pen) were randomly selected for carcass evaluation. Carcass lean content was increased (P < 0.0001) and carcass fat content was decreased (P < 0.0001) in animals treated with rpST by daily injection. Animals treated with rpST by the slow-release implant were not different from the control animals in terms of growth performance and carcass characteristics. No overt lameness was observed in any of the pigs in the experiment. However, rpST treatment, regardless of the method of administration, increased the incidence and severity of osteochondrosis and reduced glycosaminoglycan concentration in the cartilage of the weight-bearing area of humeral and femoral condyles. These changes were independent of enhanced growth rate and carcass lean content. The results indicated that somatotropin treatment predisposes pigs to osteochondrosis. Key words: Osteochondrosis, growth rate, growth hormone, joint cartilage, pigs

Frequency and severity of osteochondrosis in horses with cervical stenotic myelopathy

SUMMARY We compared the frequency and severity of osteochondrosis lesions in young Thoroughbred horses with cervical stenotic myelopathy (csm) vs that in clinically normal Thoroughbreds of the same age. All lesions of the cervical vertebrae and appendicular skeleton were classified histologically as osteochondrosis or nonosteochondrosis and were measured for severity. Minimal sagittal diameter was significantly smaller in horses with csm from C2 through C6; no difference was detected at C7. Severity of cervical vertebral osteochondrosis was greater in the horses with csm, however frequency was not different. Frequency and severity of nonosteochondrosis lesions were not different in cervical vertebrae or appendicular skeleton. Frequency and severity of appendicular skeleton osteochondrosis lesions were both greater in horses with csm. Osteochondrosis and nonosteochondrosis lesions were more severe on facets at sites of compression than on facets at noncompressed sites in horses with csm. However, compression was also observed at sites with no articular facet lesions. The association of widespread osteochondrosis and spinal canal narrowing with csm suggests csm may represent a systemic failure in the development or maturation of cartilage and bone.

Severity of osteochondrosis in three genetic lines of Duroc swine divergently selected for front-leg weakness

The relationship of osteochondrosis to genetic differences in front-leg structure in Duroc swine was investigated by using offspring from low (poor front-leg structure), control (intermediate front-leg structure) and high (superior front-leg structure) lines from a 5-generation divergent selection experiment for front-leg structure. Ten pigs of each sex and line were chosen at random and visually scored for front- and rear-leg structure. After slaughter, synovial fluid was collected and cultured from 3 major joints of each front leg, and macroscopic, microradiographic and histologic osteochondral lesion scores were obtained for the articular cartilage and growth plates of several areas of both front legs and of the left rear leg. Lesion scores ranged from 0 to 3 or 0 to 5 with 0 being best. Osteochondrosis data were analyzed by using a mixed threshold model, which included the effects of line, sire/line, sex and side of the pig and a covariate for slaughter weight or age of slaughter. Means of front-leg structure scores on a scale of 1 (worst) to 9 (best) were 3.02 ± 0.17 (low line), 5.67 ± 0.21 (control line) and 7.91 ± 0.21 (high line) ( P < 0.05). The high line had lower osteochondral lesion scores ( P < 0.05) for the proximal radius/ulna than did the control or low lines, but severity of osteochondrosis at the other joints and growth plates was not different between lines. Boars had greater severity of lesions than did gilts ( P < 0.01) for the growth plate of the distal ulna and articular cartilage of the distal femur. Mycoplasma hyosynoviae was isolated from joints of a few pigs, however, no relationship between isolation of the organisms and line was observed. These results suggest that, although osteochondrosis may play a role, it is not the primary cause of front-leg weakness in Duroc swine.

LEG WEAKNESS AND OSTEOCHONDROSIS IN SWINE: A REVIEW

Leg weakness (lameness) in swine is a problem resulting in economic loss. Osteochondrosis, a noninfectious condition manifested as a failure of endochondral bone formation, is thought to be a principal predisposing cause of leg weakness. Frequent sites of osteochondrotic lesions include the medial condyles of the femur and humerus, semilunar notch of the ulna and the distal ulnar physis. Osteochondrosis results in focal thickening of cartilage with the affected portion of cartilage, which fails to ossify, retained in the subchondral bone. The retained cartilage is frequently associated with chondrocyte death and loss of extracellular matrix proteoglycans. An advanced degree of the condition is observed as osteochondrosis dissecans or secondary osteoarthrosis, and frequently causes lameness of animals. Changes in proteoglycan structure are noted in severely affected porcine joint cartilage. Causes of leg weakness and osteochondrosis remain unclear. Many researchers suggest that mechanical overloading is responsible for the relatively high frequency of osteochondrotic lesions on the weight-bearing surfaces of affected bones. Leg weakness and joint lesions have been studied in relation to various factors associated with animal feeding and management practices (e.g., growth rate, exercise and floor types). Rapid weight gain has often been suggested to be related to the incidence of osteochondrosis, but results are not consistent among experiments reported. The incidence of osteochondrosis is very high (&gt; 90% in one study) even in genetically selected slow-growing pigs, and most attempts to prevent or reduce the incidence of osteochondrosis are unsuccessful. A certain amount of exercise is essential for normal growth of bone and cartilage, but data are lacking concerning whether pigs under normal confinement systems need additional exercise. Experiments with enforced exercise on treadmill or brisk walking suggest that the treatments have little effect on soundness of limb joints of swine. It is unlikely that the incidence of joint lesions could be reduced by changing type of floors studied so far. It has been reported that dietary supplementation of various minerals and vitamins within wide limits has little effect on the incidence or severity of osteochondrosis, suggesting that prevention of joint lesions by nutritional means is also difficult. Genetic studies suggest that the heritabilities of leg weakness and osteochondrosis are low to moderate (0.1 – 0.3), and therefore the problem will be difficult to solve by selection alone. Other factors including carcass characteristics, sex or breed are also discussed in realtion to leg abnormalities. It is possible that pathogenesis of or susceptibility to joint abnormality differs among animals studied, even in the same experiment, resulting in a failure to observe a correlation between a certain factor and the occurrence of leg abnormalities. The last part of this review covers studies examining recovery of pigs from lameness or osteochondrosis including therapeutic means. Treatment of osteochondrotic lame boars by intramuscular administration of glycosaminogiycan polysulfate (GAGPS) improves their locomotory ability. Key words: Leg weakness, osteochondrosis, joint cartilage, bone, growth, pig

EFFECT OF FLOOR TYPE ON THE SEVERITY OF FOOT LESIONS AND OSTEOCHONDROSIS IN SWINE

Sixty-seven pigs were weaned at 5 wk of age and assigned to pens with either plastic-coated expanded metal or woven-wire floorings. The feet of each pig were examined at weaning and at the end of a 28-d starter period for soundness. Eleven gilts which had been on plastic-coated flooring and 12 gilts which had been on woven-wire flooring were moved at the end of the starter period to 1.2 × 1.2-m pens with the same floor types. These pigs were fed ad libitum until slaughter at 94 kg bodyweight. At weaning, the incidence of foot lesions was only 7%. Floor type did not have any significant (P &gt; 0.05) effect on average daily gain, average daily feed intake or feed:gain ratios of pigs during the starter (8–22 kg), grower (22–55 kg) or finisher (55–94 kg) periods. Foot lesions were most severe (P &lt; 0.01) in starter pigs which were penned on woven-wire flooring. There was also a tendency (P &lt; 0.06) towards more severe hind-toe lesions in 94-kg gilts which were penned on woven-wire flooring. In general, the lateral digits of the feet of these gilts had more severe lesions (P &lt; 0.01) than the medial digits. The severity of osteochondrosis of the condyles of the femur and humerus, of the articular cartilage of the proximal ulna and radius and of the distal ulnar physis were not significantly (P &gt; 0.05) affected by floor type. The influence of floor type on the locomotory system appeared therefore to be confined to local foot abrasions and did not extend to the knee and elbow joints. Key words: Swine, floor, foot, lesion, osteochondrosis

Genetic Analysis of Osteochondrosis and Leg Weakness in the Swedish Pig Progeny Testing Scheme

Abstract Information about leg weakness scored before slaughter (1 =worst, 3=best) and osteochondrosis in elbow and knee joints scored after slaughter (0=best, 5=worst) in the Swedish pig progeny testing scheme were analysed. The data comprised information on 9 886 pigs (5 568 Landrace and 4318 Yorkshire) beginning test from November 1981 to September 1984. For the two osteochondrosis scores and leg weakness, Landrace was the inferior breed and castrates the inferior sex. The incidence and severity of osteochondrosis was highest in the knee joint, compared with the elbow joint. Only severe joint lesions were correlated with increased incidence of clinical signs of leg weakness. Pigs with inferior constitution grew faster during the first part of the test period, but slower at the end of test compared with constitutionally better pigs. Heritabilities of leg weakness score were 0.14±0.03 for Landrace and 0.11 ±0.03 for Yorkshire. Heritabilities for elbow joint scores for osteochondrosis were 0.21±0.03 and 0.25±0.04 for Landrace and Yorkshire respectively. Corresponding heritabilities for knee joint scores were 0.33±0.04 and 0.35±0.05. Indications of unfavourable genetic correlations between constitution and growth rate and between constitution and lean percentage were found.

EFFECT OF DIETARY CALCIUM AND PHOSPHORUS LEVELS ON PERFORMANCE, BONE BENDING MOMENT AND THE SEVERITY OF OSTEOCHONDROSIS AND LAMENESS IN BOARS AND GILTS SLAUGHTERED AT 100 OR 130 KG BODY WEIGHT

Ninety-six crossbred gilts and 96 crossbred boars averaging 20 kg were assigned to a factorial arrangement of three dietary calcium-phosphorus (Ca-P) levels and two slaughter weights (100 or 130 kg). The Ca-P regimens were based on (1) National Academy of Sciences-National Research Council (NAS-NRC)(1979), (2) Agricultural Research Council (ARC) (1981) and (3) 130% of ARC (1981) recommendations for grower and finisher swine. All pigs were fed ad libitum grower diets (0.60–0.50, 0.81–0.63, 1.05–0.82% Ca-P) from 20 to 55 kg and finisher diets (0.50–0.40, 0.72–0.54, 0.94–0.70% Ca-P) to 100 kg or 130 kg liveweight. At 100 kg liveweight 16 boars and 16 gilts from each of the Ca-P treatment groups were selected at random and slaughtered. The remaining pigs within each Ca-P group were allowed feed ad libitum or at 70% of ad libitum from 100 kg until slaughter at 130 kg. There was no significant effect of the three respective dietary Ca-P regimens on average daily gain, average daily feed intake, or feed/gain ratio of pigs during the 20- to 100-kg growth period. Metacarpal bending moment and femoral ash content increased (P &lt; 0.05) in response to the first dietary Ca-P increment. There was a significant (P &lt; 0.05) positive response of femoral ash content but not of bone bending moment to the second Ca-P increment. The incidence and severity of osteochondrosis of the femur, humerus, radius and ulna and leg soundness scores were unimproved (P &gt; 0.05) by feeding elevated dietary Ca-P levels. There was no significant effect of ad libitum vs. restricted feeding during the 100- to 130-kg growth period on bone ash, bone bending moment or cartilage condition scores. Boars had significantly (P &lt; 0.01) greater average daily gain and lower feed/gain ratio during the 20- to 100-kg growth period but they had more severe (P &lt; 0.01) osteochondrotic lesions of the elbow joint and a lower (P &lt; 0.001) femoral ash content than gilts. Correlation coefficients between cartilage soundness scores and bone ash content or bending moment were nonsignificant (P &gt; 0.05). The results suggest that while bone ash content and bending moment respond positively to elevated Ca-P levels in excess of NAS-NRC (1979) recommendations, the incidence and severity of joint lesions and leg soundness scores are not reduced by maximizing bone mineralization. Key words: Osteochondrosis, calcium, phosphorus, swine

EFFECT OF GROWTH RATE ON THE INCIDENCE OF OSTEOCHONDROSIS IN GROWING SWINE

Eighty-eight, 4-wk-old Yorkshire × Landrace pigs (44 barrows and 44 gilts) averaging 8.0 kg were used to study the effect of growth rate on the incidence of osteochondrosis and some characteristics of hind limb bones. Forty-eight pigs (Group I) were fed control diets through the starter to finisher phases, while for the remaining 40 pigs (Group II), nutrient densities of starter and grower diets were increased to enhance growth rate. At an average liveweight of 94 kg, animals wer slaughtered, and humeri, ulnae, radii, and femurs were visually and histologically examined for soundness of cartilage and subchondral bone. Average daily gain was greater for Group II than for Group I during both the starter (0.58 vs. 0.43 kg, P &lt; 0.01) and grower (0.84 vs. 0.74 kg, P &lt; 0.05) phases, as was intended, and also greater (0.74 vs. 0.68 kg, P &lt; 0.05) for Group II for the overal experimental period. The faster growth rate in Group II did not affect (P &gt; 0.05) the incidence and severity of osteochondrosis in any joint (or bone) site examined. This was consistent with the nonsignificant (P &gt; 0.05) correlations between growth rate and soundness scores of joint and bone, and the similarity (P &gt; 0.05) of the soundness scores of pigs with fast growth rate (average daily gain, 0.82–1.00 kg), intermediate growth rate (0.74–0.76 kg), and slow growth rate (0.53–0.67 kg). Bone characteristics of the femur, tibia, and metatarsal bones were not influenced (P &gt; 0.05) by growth rate. Key words: Growth rate, osteochondrosis, bone characteristics, swine

Cross Breeding Experiments with Swine. Influence of Different Combinations of Breed on Frequency and Severity of Osteochondrosis

Cross Breeding Experiments with Swine. Influence of Different Combinations of Breed on Frequency and Severity of Osteochondrosis