Leg weakness in pigs. II. Litter differences in leg weakness, skeletal lesions, joint shape and exterior conformation

Investigations were carried out concerning possible litter differences in locomotory ability and exterior conformation, and possible litter and sire group differences in the occurrence of skeletal lesions and in joint shape. The animals were from a breed experiment involving 6 litters, 8 feeding experiments involving 64 litters, and a selection experiment totalling 70 litters and 25 sire groups distributed in 3 lines. One hundred and twenty-one out of 285 P values for litter or sire group differences were statistically significant (P < 0.05). This shows, with reservations concerning the possibility that different environmental conditions up to 20 kg live weight may have produced a litter effect on pigs from the breed and feeding experiments, that heredity plays a significant part in the leg weakness complex. It seems justified to conclude that it partly is the inheritance of certain joint shapes and exterior conformational features, which influence the degree of joint lesions and locomotory ability and give rise to litter differences. This gives the theoretical possibility of selecting for more lasting joints and better locomotory ability using criteria based on joint shape and exterior conformation.     

Osteochondrosis and arthrosis in pigs. I. Incidence in animals up to 120 kg live weight

Joint and bone lesions in growing pigs are described on the basis of post-mortem examination of 341 gilts, boars or castrates from 10 to 120 kg live weight, and 869 separate bones from pigs between 80 and 115 kg live weight at slaughter. No evidence of rickets or generalized osteodystrophia fibrosa was found. Lesions occurred in both sexes. The typical osteochondral lesions were most often symmetrical, occurred at certain sites in joints and epiphyseal plates and were most obvious in the elbow and stifle joint, and in the distal epiphyseal plate of the ulna. Lesions of varying degree could be demonstrated in most pigs at 90–100 kg live weight. The use of the diagnosis osteochondrosis is suggested for local primary non-inflammatory disturbances which lead to a failure of endochondral ossification in joint cartilage as well as in epiphyseal plates. The diagnosis arthrosis is used when the superficial layer of the joint cartilage is affected. Investigations of the early changes in the medial condyle of the femur suggest that the osteochondral lesions start in the deep layers of the joint cartilage. Arthrosis occurred frequently in the lumbar intervertebral joints of Norwegian pigs. Otherwise the lesions appeared to be identical with those described from other countries.     

Osteochondrosis and arthrosis in pigs. 3. A comparison of the incidence in young animals of the Norwegian Landrace and Yorkshire breeds

An investigation concerning the occurrence of osteochondrosis and arthrosis in 2 materials totalling 63 pigs of the Landrace breed and 63 of the Yorkshire breed is described. The animals were bred under the same conditions of feeding and housing. The differences should therefore mainly be of genetic origin. Both breeds were highly improved, Landrace the most. In general, Yorkshire pigs showed a lower incidence and a less marked degree of osteochondrosis and arthrosis than Landrace pigs. Statistically significant differences (P < 0.01) were demonstrated in the distal epiphyseal plate of the ulna, in the intervertebral joints of the lumbar region and in the medial condyle of the femur in 1 of the materials. The Landrace pigs had longer bodies, broader hindquarters, shorter femurs, and the stifle had a different shape as compared with Yorkshire pigs. There thus seemed to be a connection between exterior features, joint and bone shape and the occurrence of joint lesions. Differences among litters within breed were also demonstrated.     

Osteochondrosis and Arthrosis in Pigs: VI. Relationship to Feed Level and Calcium,Phosphorus and Protein Levels in The Ration

Eight feeding experiments, each comprising 48 boars or gilts, were carried out. The factors feed level, Ca, P and protein levels were varied within practical physiological limits. The animals were slaughtered at close to 100 kg live weight. Lesions in joints and bones were of a noninfectious, non-rachitic nature and of the osteochondrosis and arthrosis type. Ten to 12 g Ca and approx. 10 g P/kg ration gave histomorphologically seemingly more optimum structure of the spongious bone tissue and a higher ash percentage in bones than 7 g Ca and 6 g P, or unbalanced mineral levels in the ration. However, there was no significant difference in degree or incidence of joint and bone lesions between mineral groups. Neither were there such differences present between feed level groups or protein level groups. This may for the feed level groups be partly due to the low feed level pigs having a longer period of time during which they were highly susceptible to the development of lesions. The low feed level animals had longer long bones at 100 kg live weight than the high feed level animals. The length of the vertebral column was, however, approximately similar in the 2 feed level groups. The angles of the condyles and head of the femur according to the length axis were influenced by feed level or growth rate, most probably by an effect on the endochondral ossification.     

Osteochondrosis and arthrosis in pigs. V. A comparison of the incidence in three different lines of the Norwegian Landrace breed

Investigations were carried out on 289 slaughter pigs, 56 breeding boars, and 51 breeding sows in a selection experiment started in 1964. The animals belonged to 4th–6th generations. One line has been selected for thin backfat and rapid growth (LBL) and 1 for thick backfat and slow growth (HBL). In addition a control line (GL) not subjected to selection was established in 1967. The pigs were kept as far as possible under identical conditions of housing and feeding, so that differences between lines should be primarily of genetic nature. The skeleton, measured as the length of bones and vertebral column, was statistically significantly smaller (P < 0.01) in HBL than in CL and LBL. The difference between CL and LBL was slight. No essential proportional changes in the skeleton took place. Patho-anatomical findings in the skeleton comprised, in all 3 lines, osteochondrosis, arthrosis, degeneration of the intervertebral discs, spondylosis, and epiphyseal separation. There were a lower incidence and statistically significant (P < 0.01) lower degree of total lesions in joints and bones in HBL, both as regards the slaughter pigs, boars and sows. The fact that the lumbar region of the vertebral column consistently showed the greatest difference in degree and incidence of lesions between the lines, suggests that this becomes the weakest skeletal part in pigs with a rapidly growing skeleton.     

Osteochondrosis and arthrosis in pigs. II. Incidence in breeding animals

Joint and bone lesions in Norwegian breeding pigs are described on the background of an investigation involving 174 sows and 155 boars from 7 months to 4½ years old. Lesions, which consisted predominantly of arthrosis, degeneration of intervertebral discs, spondylosis and epiphyseal separations, were demonstrated frequently in both sexes. Osteochondrosis, a condition previously demonstrated frequently in slaughter pigs, had either completely healed, undergone repair or developed into an arthrosis by the time the animal reached an age of about 1½ years.Whereas a higher incidence of arthrosis of the intervertebral joints was found in boars than in sows, the reverse was true as regards degeneration of the intervertebral discs and anchylosing spondylosis. Possible reasons for this are discussed. Norwegian pigs show a higher incidence of lesions in the lumbar region of the vertebral column than has been described up to the present time in other countries.     

Effects of glycosaminoglycan polysulfate treatment on soundness, hyaluronic acid content of synovial fluid and proteoglycan aggregate in articular cartilage of lame boars.

Eighteen lame boars were equally assigned to two treatment groups based on initial bodyweight and leg soundness. The boars were injected intramuscularly with an aqueous solution of glycosaminoglycan polysulfate or saline on day 0, 5, 10, 15, 20 and 25 and killed on day 27. The glycosaminoglycan polysulfate treatment significantly (P less than 0.05) improved leg soundness score, and resulted in an increase (P less than 0.06) in the hyaluronic acid concentration of the cubitus joint synovial fluid, and an increase (P less than 0.05) in the proportion of aggregated proteoglycans in the articular cartilage of the medial femoral condyle. Feed intake, growth rate and articular cartilage soundness score for the cubitus and stifle joints were not significantly (P greater than 0.10) affected by the treatment.     

Effects of divergent selection for leg weakness on angularity of joints in Duroc swine

Sixty Duroc pigs, representing offspring of three lines from the fifth generation of divergent selection for leg weakness, were examined to determine correlated responses in joint angularity. The lines were low, control, and high, with the latter having superior front leg structure. At approximately 100 kg, 10 pigs of each sex and line were scored for front and rear leg structure and movement. The shoulder, elbow, carpal and hock joints were measured for resting angles and range of motion. The model to analyze the data included the effects of line, sire, sex and side and covariable for weight. High-line pigs had significantly smaller (P less than .05) resting angles of the elbow joint than did control- or low-line pigs. The low-line pigs, however, had significantly smaller resting angles at the carpal joint (P less than .01) and greater resting angles at the hock joint (P less than .05) than did control- or high-line pigs. The low-line pigs had fewer degrees extension at the elbow joint and fewer degrees flexion at the carpal joint than did control- or high-line pigs. High-line pigs had fewer degrees of flexion of the elbow joint than did control-or low-line pigs. Resting angles and range of motion for the elbow and carpal joints were less on the left side than on the right side. Males had greater degrees of extension and total degrees of movement at the elbow joint than did females. Selection for different degrees of leg weakness resulted in accompanying alterations in angularity of joints.     

Evaluation of the effect of limited food consumption on radiographic evidence of osteoarthritis in dogs

OBJECTIVE: To determine prevalence of radiographic evidence of osteoarthritis in 4 diarthrodial joints of dogs with restricted feed intake, compared with dogs without restricted feed intake. DESIGN: Paired feeding study. ANIMALS: 48 Labrador Retrievers. PROCEDURE: Dogs in litters from 7 dams and 2 sires were paired by sex and weight within litters and randomly assigned to a control-fed group or a limit-fed group that received 25% less food than the control-fed group. Radiographic evaluation of prevalence and severity of osteoarthritis in the hip, shoulder, elbow, and stifle joints was performed when dogs were 8 years of age. RESULTS: Radiographic evidence of osteoarthritis that affected multiple joints was significantly more common in the control-fed group than in the limit-fed group. Prevalence of lesions in the hip joint was 15/22 in the control-fed group and 3/21 in the limit-fed group. Prevalence of lesions in the shoulder joint was 19/22 in the control-fed group and 12/21 in the limit-fed group; lesions in this joint were generally mild. Severity, but not prevalence, of osteoarthritis in the elbow joint was greater in the control-fed group than in the limit-fed group. CONCLUSIONS AND CLINICAL RELEVANCE: Prevalence and severity of osteoarthritis in several joints was less in dogs with long-term reduced food intake, compared with control dogs. Food intake is an environmental factor that may have a profound effect on development of osteoarthritis in dogs.     

POLYARTHRITIS OF PIGS IN WESTERN AUSTRALIA: THE ROLE OF ERYSIPELOTHRIX RHUSIOPATHIAE

A 3-month survey of polyarthritis in pigs was carried out at 3 metropolitan abattoirs in Western Australia. The incidence of total carcass condemnations for polyarthritis was 0.46% and partial condemnation for "arthritis" 1.66% of 15,919 pigs. It was demonstrated that the majority of joint lesions found in either total or partial condemnations were identical pathological conditions, usually differing only in the number of joints involved. Erysipelothrix rhusiopathiae was isolated from the joints of 63% of pigs condemned for polyarthritis; it appears that this organism is the most significant aetiological agent of polyarthritis in Western Australia. The role of mycoplasmas has not been determined. The groww and microscopic lesions seen in affected joints were those of a non-suppurative proliferative polysynovitis. The stifle and elbow joints showed the highest incidence of the most severe lesions. Pigs condemned for polyarthritis over a 6-month period were traced back to 125 farms. Eighty per cent of pigs that had been condemned for polyarthritis had not been vaccinated against erysipelas or were of doubtful vaccination status. Only 3% of pigs had been vaccinated as recommended. The results would suggest that erysipelas vaccine is not directly implicated in the pathogenesis of polyarthritis. The majority of pigs condemned for polyarthritis originated from poorly managed small piggeries run as sideline enterprises. There was no significant pattern to the geographical distribution of polyarthritis cases in Western Australia. Likewise, no significant realtionship was established between polyarthritis condemnations and either breed, sex or bodyweight of thepigs involved.     

湿热环境对后备公猪采食行为和饲料效率的影响

为分析中国南方高温高湿环境对扬翔华系杜洛克后备公猪在生长育肥期采食量、采食时间等采食行为和饲料效率的影响,本研究以扬翔华系杜洛克后备公猪在FIRE测定站的998 195条采食记录为基础,使用温湿度自动监测设备实时监测圈舍温度和湿度。采用R 3.5.1软件统计猪群昼夜采食节律,运用线性混合模型分析不同温湿度水平采食行为和饲料效率的差异,并尝试建立扬翔华系杜洛克生长公猪实际采食量预测模型。结果表明:扬翔华系杜洛克生长猪的采食行为呈昼夜节律变化,受日温度变化影响;当环境温度在20～24℃,温湿指数(THI)在66～71时,生长猪的饲料转化率(FCR)和剩余采食量(RFI)均较低;当环境温度超过25℃,THI超过74时,FCR最高可提高13.98%,RFI最高可提高182.92%。综上可知,在华南地区湿热环境下,当环境温度控制在18～22℃、THI在65～70时,扬翔华系杜洛克生长公猪的采食量较高,FCR和RFI较低,饲料效率较高。THI可作为监测生长公猪热应激的候选指标。     

Leg weakness and osteochondrosis in pigs; differences between the sexes of four breeds

Clinical observations on leg weakness (1: sound, 5: severe defects or lameness) and pathological assessments on osteochondrosis (0: no lesions, 3 or 5: severe lesions) were carried out on pigs just before and after slaughter. The animals belonged to four breeds, viz. Duroc (D: 6 ♂, 12 ♀), Piétrain (P: 16 ♂, 6 ♀), Great Yorkshire (GY: 22 ♂, 13 ♀) and Dutch Landrace (NL: 6 ♂, 34 ♀, 44 ♂).Between breeds the leg weakness scores in boars' front legs showed minor differences (1.7–2.3); the hind legs showing more (3.0–3.8). In gilts the fore legs of the Piétrains showed the highest (3.7) incidence of defects. The hind legs in the D-gilts (2.5) scored best. The differences between the sexes were not of the same tenor in the various breeds.Between breeds within sexes, the D-breed and the GY-gilts showed the highest incidence of osteochondrosis in the fore legs; within the breeds the D, P and NL-gilts tended to be better than the corresponding boars. The boars' femur was less affected in the D (1.5) and NL-breeds (2.3) compared to the Piétrains (3.6) and GY (2.8). The gilts' medial femoral condyle showed the highest incidence of osteochondrosis in the P-breed (4.2). Within breeds the D and NL-boars were better than the gilts. The NL-barrows were the most affected within that breed.It was concluded that the degree of leg weakness and osteochondrosis of one sex in a breed cannot be translated to the other sex within that breed, nor to the same sex of another breed.     

Effect of dietary sodium bicarbonate on leg structure in Duroc swine that differ genetically for leg weakness

Two trials were conducted to evaluate the effect of dietary replacement of .30% sodium chloride (NaCl) with a sodium-equivalent amount of sodium bicarbonate (NaHCO3) on leg weakness in swine. Three lines of Duroc swine established by six generations of divergent selection for front leg structure were used. In the first trial, a total of 80 low-line (increased leg weakness), 75 high-line (decreased leg weakness), 80 control-line (intermediate leg weakness) and 80 high x low pigs were used. Pigs were assigned within litter to an experimental or control diet and tested from approximately 37 to 104 kg live weight. The experimental diet contained .43% NaHCO3, replacing .30% NaCl in the control diet. Pigs had ad libitum access to feed. In the second trial, 48 high- and 48 low-line pigs were fed the same diets from 29 to 104 kg. At the completion of each trial, pigs were scored for various leg traits. The model used for statistical analyses included the effects of replicate, genetic line, dietary treatment and the dietary treatment x genetic line interaction. Trials were analyzed separately. Results indicated that there was no significant improvement in clinical signs of leg weakness due to dietary supplementation with NaHCO3 for front leg structure and movement, rear leg movement or rear toe size. Rear hock angle was improved in Trial 1 (P less than .05) but was reduced in Trial 2 (P less than .10).(ABSTRACT TRUNCATED AT 250 WORDS)     

Lysine requirement of fattening boars in respect to their performance. 1. Influence of the consumption of energy and amino acids on the fattening performance

With a total number of 157 boars 9 feeding variants with different levels of energy and amino acids were checked. The weight increase per fattening day and the energy and lysine expenditure per kg live weight increase were determined. The insufficient supply with lysine had negative effects on the live weight increase and the energy expenditure during the whole fattening period. Between the variantes with a high supply with amino acids (120%) and the supply according to standard (100%) no significant differences concerning the live weight increase could be ascertained up to 90 kg live weight. Between 90 and 120 kg live weight the animals in the variant with medium energy level and 120% lysine supply achieved significantly higher increases than those in the standard variant. Up to 90 kg live weight the energy expenditure for all groups amounted to 2,08 kEFs (energetic feed units for pigs) per kg live weight increase. The most suitable results were achieved by the animals which received the variants rich in energy (1,760 resp. 1,770 kEFs per kg live weight increase). Above the 90 kg live weight limit the energy expenditure rose considerably, remained however under 2,000 kEFs per kg live weight increase for the boars of the variant with medium energy level and 120% lysine supply as well as for the variant rich in energy and 100% lysine supply. The lysine expenditure in the first variant amounted to 25.1 g per kg live weight increase and for the variant rich in energy to 20.6 g lysine per kEFs.     

Determination of the anatomic communications among compartments within the carpus, metacarpophalangeal and metatarsophalangeal joints, stifle joint, and tarsus in llamas

OBJECTIVE: To determine the anatomic communications among compartments within the carpus, metacarpophalangeal and metatarsophalangeal joints, stifle joint, and tarsus in llamas. SAMPLE POPULATION: 88 limbs from 22 llamas necropsied because of reasons unrelated to disease of the carpus; tarsus; or metacarpophalangeal, metatarsophalangeal, or stifle joints. PROCEDURE: 1 compartment (randomly assigned) of each joint was injected with blue latex solution. Communication between joint compartments was determined by observation of latex in adjacent compartments following frozen sectioning. RESULTS: Of the 44 carpi, 30 (68%) had anatomic separation between the radiocarpal and middle carpal joints, whereas the remaining 14 (32%) had communication between the radiocarpal and middle carpal joints. In the metacarpophalangeal or metatarsophalangeal joints, medial and lateral joint compartments remained separate in 83 of 88 (94%) joints injected. The tibiotarsal and proximal intertarsal joints communicated in all tarsi examined, whereas 14 of 38 (37%) communicated between the proximal intertarsal and distal intertarsal joints. Communication between the distal intertarsal and tarsometatarsal joints was detected in 17 of 25 (68%) specimens; all 4 tarsal joints communicated in 11 of 42 (26%) specimens examined. Examination of 33 stifle joints that were successfully injected revealed communication between the femoropatellar, medial femorotibial, and lateral femorotibial joints. CONCLUSIONS AND CLINICAL RELEVANCE: These data suggest that it is important to determine the joint communications specific to each llama prior to treatment of septic arthritis. The metacarpophalangeal or metatarsophalangeal joint compartments may be considered separate, although the lateral and medial compartments infrequently communicate along the proximal palmar or plantar aspect.     

Increasing daily feeding occasions in restricted feeding strategies does not improve performance or well being of fattening pigs

Background

The natural feeding behaviour of the pig is searching for feed by rooting activities throughout the day; self-feeding pigs randomly space their eating and drinking periods throughout the day consuming ten to twelve meals per day. Pigs in conventional fattening pig production are normally fed 2–3 times daily with the feed consumed within 15 minutes. The aim of this study was to determine if more frequent feedings could improve the performance of conventionally kept fattening pigs.

Methods

The experiment was carried out on 360 fattening pigs (27–112 kg live weight), weighed and assigned to pens stratified by weight and sex. Each treatment group consisted of 180 pigs, allocated to 20 pens with nine pigs in each pen. To evaluate how more feeding occasions affects performance and well-being the pigs were divided into two groups and fed three (control group) or nine (treatment group) times daily. The same total amount of liquid feed was fed to each group and the feed ration was correlated to the live weight of the pigs. All weight and slaughter recordings were made individually and recordings of feed consumption were made pen-wise. At slaughter the stomach of each pig was examined for lesions in the pars oesophagea and scored on a scale from 1–6.

Results

Frequent feeding occasions influenced both performance and status of gastric lesions of the pigs adversely. Pigs in the treatment group grew slower compared to pigs in the control group; 697 g/day (± 6.76) versus 804 g/day (± 6.78) (P < 0.001) with no difference in within-pen variation. There was also a lower prevalence of gastric lesions within pigs in the control group (2.4 (± 0.12) compared to 3.0 (± 0.12) (P < 0.01)). There was a positive correlation between gastric lesions in the treatment group and daily weight gain (r = 0.19; P < 0.01).

Conclusion

Increased daily feeding occasions among group housed pigs resulted in a poorer daily weight gain and increased mean gastric lesion score as compared with pigs fed three times daily. This may be a consequence of more frequently occurring competition for feed in the treatment group. The present study does not support increased daily feeding occasions in fattening pigs.     

Arthritis of the canine stifle joint.

A survey of cadaver material was undertaken in order to determine the prevalence of arthritis of the canine stifle joint. One hundred and fifty unselected cadavers were obtained from veterinary practices for this purpose, and their stifle joints were radiographed and dissected to discover abnormalities. Thirty-one dogs (20 per cent) had stifle arthritis and in all except one the lesions were characteristic of osteoarthritis. In the exceptional case infection was the cause. A mechanical derangement was present in 20 of the 54 affected joints, in the form of rupture of the anterior cruciate ligament (10), meniscal tears (9) and patellar dislocation (1). The cause of the arthritis in the other 33 joints is unknown.     

Selenium toxicity and porcine focal symmetrical poliomyelomalacia: description of a field outbreak and experimental reproduction.

An acute afebrile paretic condition was diagnosed in 18 of 225 feeder pigs between eight to ten weeks of age. Nine pigs died acutely, seven pigs were euthanatized and two appeared to recover. Macroscopic lesions in the ventral horns of the cervical and lumbar/sacral spinal cord enlargements consisted of focal, bilateral, depressed areas. Histopathologically, the lesion consisted of endothelial proliferation, glial cell reaction and microcavitation. Similar lesions were observed in some brain stem motor nuclei. High selenium levels were detected in the pig feed and in pig tissues and blood. Two of five experimental pigs fed a commercial grower ration and supplemented with 52 ppm selenium as sodium selenite developed paresis and paralysis after a 29 day feeding trial. Histopathological lesions of focal symmetrical poliomyelomalacia confined to the cervical and lumbar/sacral spinal cord enlargements, and identical to those in the field cases, were produced. Select brain stem motor nuclei were also affected.     

Interrelationships between sex and exogenous growth hormone administration on performance, body composition and protein and fat accretion of growing pigs

Forty-five pigs with an average initial live weight of 60 kg were used to investigate the effects of daily exogenous porcine pituitary growth hormone administration at two dose levels (pGH; 0, excipient buffer injected, and 100 micrograms.kg-1.d-1) for a 31-d period on the performance and body composition of boars, gilts and barrows allowed to consume feed ad libitum. Excipient boars consumed less feed, exhibited faster and more efficient growth (P less than .01) and produced less fat and more protein and water (P less than .01) in the empty body compared with excipient barrows, which in turn contained more fat and less water (P less than .05) in the empty body than did excipient gilts. These differences were largely eliminated by pGH administration, which induced differential effects in growth performance and body composition in boars, gilts and barrows. Growth hormone administration improved growth rate by 13, 22 and 16% and feed conversion efficiency by 19, 34 and 32% in boars, gilts and barrows, respectively. The reduction of body fat content (g/kg) elicited by pGH was 22, 36 and 33% for boars, gilts and barrows, respectively, with a corresponding increase (P less than .01) of body protein and water content. The magnitude of the pGH responses was greatest for gilts and barrows compared with boars, negating intrinsic sex-effect differences in growth performance and body composition of pigs. Pigs used in this study and treated with pGH exhibited a rate of protein deposition (approximately 225 g/d) far greater than previously reported, and as such redefine the genetic capacity for lean tissue growth by the pig.     

The effect of replacement of 0.30% sodium chloride by 0.43% sodium bicarbonate in rations of fattening pigs on leg weakness, osteochondrosis and growth

The effect of replacing dietary sodium chloride by sodium bicarbonate on leg weakness, osteochondrosis and growth in young fattening pigs was studied in two experiments using 104 and 126 animals. The experimental pigs were fed 0.43% dietary sodium bicarbonate, which replaced the sodium chloride (0.30%), was present in the diets of the control groups. It was found that the clinical symptoms of leg weakness could be improved significantly in the experimental group which received bicarbonate. No positive effects on osteochondrosis, however, could be shown. The treated animals even tended to have more severe osteochondral lesions. Reasons for the negative tendency are discussed. Daily weight gain and food conversion were not influenced by the experimental bicarbonate diet excluding a chloride deficiency. Differences in carcass grading were not significant, although barrows fed the NaHCO3-containing diet tended to score better, while the carcass quality of the experimental gilts was slightly less in comparison to the control animals.