Systemic cartilage defect in a calf

A 6-month-old Ayrshire calf had a systemic growth defect of cartilage. The most severe changes occurred in articular cartilage and epiphyseal plates of long bones where disturbance of ossification, necrosis, erosion, vascular invasion, proliferation of cartilaginous and fibrous tissue were seen. The lesions probably were the result of a failure in the initial phases of ossification and mechanical pressure was responsible for their severity in the cartilage of the limbs.     

A morphological study of skeletal development in turkeys during the pre-hatching stage

Skeletal chondrofication, ossification and growth of turkey embryos were investigated and analysed to enable assessment of the developmental status and evaluation of the experimental effects on skeletal development, skeletal mutations and development of cultured embryos. Ten embryos were prepared every 24 h from 8 to 28 days of incubation. The fixed embryos were cleared and stained in toto with Alcian blue & Alizarin red for cartilage and ossified components, respectively. Observation of the skeleton was performed under a stereoscopic microscopy, with special attention to the timing of chondrofication and ossification of the bones. The first occurrence of the primary ossification centres was observed in the femur, tibiotarsus, and the dentary and supra-angular of the mandible on the 12th day, followed immediately by the other long bones. Skeletal features of the skull were determined to show the latest appearance of cartilage and ossification. Hence, all elements of the hyolingual apparatus remained cartilaginous until hatching took place except for the ceratobranchial. Even though the vertebral column chondrified earlier as compared with the ribs and sternum, they ossified later. While chondrofication was present in all the regions of the vertebral column at the same time, ossification progressed from the cervical through caudal regions. The growth rate of the femur was eminently higher than that of the humerus with increase in time, particularly after the 20th day of incubation. This seems to be obviously natural because the eggs used in the study are from the broiler turkey, which gains giant muscle mass at a very short period; precocity is probably at the expense of the bones of the leg rather than those of the wing.     

Development of the skeleton and feathers of dusky parrots (Pionus fuscus) in relation to their behaviour

A clutch of five dusky parrots (Pionus fuscus) was observed from hatching to fully grown. They were examined radiographically from 16 to 45 days of age, a few days before the cessation of bone growth, and the development of their feathers and their behaviour were also studied. It was observed that when growing birds were removed from the nest and placed singly on a flat surface they would stand up and walk about until restrained; normally these birds would move very little and lie in an intertwined huddle that supported their relatively weak growing skeletons. At 50 days old they would climb to the nest entrance, retreating if scared. From day 51 the parrots flapped their wings vigorously inside the nest box, and they emerged at 53 days old when nearly all their large feathers had finished growing. These findings may help to explain the high rate of juvenile osteodystrophy in hand-reared parrots; premature exercise could lead to pathological deformity of the long bones, especially the major weight-bearing bone, the tibiotarsus.     

Effect of lighted incubation on embryonic growth and hatchability performance of two strains of layer breeder eggs

1. Eggs from two layer-type breeder flocks (ISA-W vs Leghorn) between 30 and 45 weeks of age were used in 4 trials to study the effects of lighted incubation on embryonic growth from 5 to 18 d of age and hatchability per cent (HP). The physical dimensions, eggshell characteristics and conductance (EC) of eggs of the two strains were compared. 2. Eggs were set in an incubator on trays either in the dark-control or under two tubes of 20-watt white fluorescent light during the first 18 d of incubation. The light intensity ranged from 1230 to 1790 lux at the surface of the eggs. Eggs were transferred to dark hatching compartments at d 19 of incubation. 3. The genetic make-up of birds influenced the physical dimensions and eggshell characteristics of eggs. ISA-W eggs had higher weight, surface area (ESA), volume (EV), width, EC, shell volume and HP, and lower ESA:EV ratio, per cent shell, shell density and dead embryos than those of Leghorn eggs. 4. Lighted incubation increased daily embryonic growth (mg/d) and HP by 3.9 and 5.9%, respectively, when compared with the dark-control incubation. 5. The physical dimensions and eggshell characteristics of eggs influenced the effects of lighted incubation on embryonic growth and HP. Lighted incubation increased embryonic growth and HP of ISA-W eggs. The increase in embryonic growth and HP of the Leghorn eggs was not significant. 6. The genetic make-up of birds influenced the physical dimensions and eggshell characteristics of their eggs and these differences in the characteristics of hatching eggs influenced embryonic growth and HP when incubated under light.     

A study of the growth of the alimentary tract of the young cockerel.

1. The growth of the alimentary tract of male domestic fowl has been described from measurements of the dry weight of the whole and component parts of the tract from hatching to 10 weeks of age. 2. Quadratic regression equations were derived to express the growth of the birds and the growth of their alimentary tracts. 3. From hatching to 2 weeks there were marked alterations in the proportions which the different parts represented of the size of the whole tract.     

Comparative cell kinetics of avian growth plates

New data on the cell kinetics of the cartilage growth plates in the chicken, budgerigar and rhea derived from studies with tritiated thymidine labelling are given. Quantitative histological measurements on growth plates from leg bones (tibiotarsus, tarsometatarsus and a phalangeal bone) in a further five species of birds are presented. Counts of flat cells and measurements of the average diameter of hypertrophic cells were made for each growth plate. These data are compared with values for the overall growth rates of the bones. The variation in sizes of hypertrophic cells was small and it is concluded that the largest factor in determining the growth rate of an avian bone is the size of the zone of flat cells.     

An inherited enchondrodystrophy in the English Pointer dog. A new disease

This report describes the clinical, radiological, pathological and genetic features of an inherited dwarfism in the English Pointer. Gross enlargement of the distal ulnar, radial and tibial growth plates occurred in the first 6 weeks of life and radiographic skeletal abnormalities were present at other sites. The enlargement was due to increase in width of the zone of hypertrophic cartilage, but the columns of chondrocytes were well ordered. By 12 weeks of age an unusual type of degeneration was present beneath the surface of articular cartilage; this developed to widespread, patchy erosion of joint surfaces by 32 weeks. The genetics are compatible with a homozygous recessive mode of inheritance.     

Relationship between the weight of hatching eggs and subsequent early performance of broiler chicks

1. The effect of egg weight on the subsequent performance of individual growing chicks was studied. Eggs from commercial broiler breeder hens were collected at 52, 55 and 57 weeks of age and incubated. The chicks were reared for 18 d. 2. Egg weight and hatched chick weight were not affected by the age of the hens during the 52 to 57-week period, but there was a close correlation between egg weight and hatching weight, irrespective of the age of the hens (r = 0.89). Chick:egg weight ratio at hatching was about 0.71 and independent of hen age. One d after hatching, chick weights had decreased by about 1.5 g. 3. The initial high correlation between egg weight and chick weight decreased markedly during post-hatching growth, becoming insignificant 5 d after hatching. At 18 d of age, however, chicks from eggs of older hens tended to be heavier than those from younger birds. The greater 18-d weights appeared to be associated more with higher food intake during that period, than with greater egg weight. 4. It was concluded that, in individual broiler chicks, the advantage of the initially higher weight attributable to a larger egg diminishes rapidly after hatching, and the main factor affecting final body weight is food intake.     

Osteological Development of the Garfish (Belone belone) Larvae

Garfish, Belone belone (Linnaeus, 1761) is an elongate, slander fish inhabiting the Eastern Atlantic and Mediterranean Sea. These fish from the Belonidae (Actinopterygii) family have important commercial value for Croatian fisheries. Samples for research were collected from experimental hatching in the Novigrad Sea. Preparation techniques included fixation in buffered formalin, trypsin clearing and staining with alcian blue and alizarin red. As little is known of garfish osteology and bone morphology, the main goal of this study was to describe ossification process in garfish fry. At hatching, no skeletal structure is present. Newly-hatched larvae also had no osteological elements. Ossification started at 7 day post-hatching (DPH) [total length (TL) 18 mm] with head bones and vertebral neural arch. Head skeleton continued to develop mostly over the period from 7 to 10 DPH. At 21 DPH (TL 49 mm), ossification process seemed to be finished, but it was not possible to distinguish borders of all bones. The primary interest of our research was to understand the growth dynamics as well as transformation of supporting body elements from cartilage to bone. At the end, developmental characteristics and functional aspects of this formation in different fish species are discussed.     

A system of grading ossification in limbs of foals to assist in radiologic interpretation.

Tetracycline-labeled bones of 23 foals from 52 to 104 days old were sectioned and macroscopically examined to assess the extent of ossification or fusion of ossification centers. A grading system was devised with which to record information about the ossification centers and growth plates. The objective was to define anatomic standards which could contribute toward obtaining an accurate radiologic interpretation. Labeled limb bones of 3 neonatal foals were similarly treated, but grading of these was limited to the consideration of whether each site was still cartilaginous or had commenced to ossify.     

Comparative observation on the growth changes of the histochemical properties and collagen architecture of the Musculus puboischiofemoralis pars medialis from Silky, layer-type and meat-type cockerels

Growth‐related changes in the histochemical properties and collagen architecture of the Musculus puboischiofemoralis pars medialis were compared among Silky, layer‐type, and meat‐type cockerels. Histochemical and immunohistochemical methods were employed and collagen architecture was studied using scanning electron microscopy. Total intramuscular collagen was also determined. The myofibers were categorized as type I, type IIA and a transitional form, type I‐tr. The proportion of type I‐tr myofibers diminished and these myofibers were transformed entirely into type I myofibers in meat‐type but incompletely in the others. The largest diameter of type I myofiber was found in layer‐type at 30 weeks of age. At 30 weeks of age, layer‐type birds had attained well‐developed perimysial collagen bundles while meat‐type birds had less developed bundles. The endomysial collagen network had a large mesh size at 1 week and then accumulated many collagen fibrils to form a felt‐like fabric of fibrils by 30 weeks of age. Silky birds developed the thickest endomysial collagen plates of all the breeds. From these results it appears that growth‐related changes in the histological structure of M. puboischiofemoralis pars medialis are not necessarily causally affected by the different growth rates of chicken breeds.     

Chondrodysplasia of Texel sheep - a new disease of suspected genetic aetiology (abstract)

A chondrodysplasia characterised by dwarfism and varus deformity of the forelimbs has been recognised over four seasons in Texel and Texel-cross lambs on three related properties. Affected lambs appear normal at birth, but by 2 weeks of age have reduced growth rate, shortened neck and legs, varus forelimb deformities and a progressive reluctance to walk. Most die within the first 4 months of life. Some affected lambs have had normal co-twins. Post mortem examination of two severely affected 3-month-old lambs revealed extensive loss of articular cartilage and exposure of subchondral bone on the weight-bearing surfaces of the proximal humeri and femurs. Articular and physeal cartilages were thicker than normal, suggesting delayed or impaired endochondral ossification. Histopathologically, there was disorganisation of chondrocytes in articular and physeal cartilage of all bones examined. In addition, there were multiple foci of chondrolysis, which coalesced in some areas to form large clefts. The chondroid matrix surrounding chondrocytes had an abnormal fibrillar appearance. One lamb that exhibited early signs of the disease died of an unrelated cause at 3 weeks of age, and although there was no erosion of articular cartilage, characteristic microscopic lesions were present in articular and physeal cartilage. Although most of the affected lambs were born on a commercial property with a mix of different sheep breeds, all had Texel genes on both sire and dam sides of the pedigree. The farmer had been purchasing his Texel rams from the same flock for several seasons. Circumstantial evidence favours a genetic aetiology, characterised by either autosomal recessive inheritance or over dominance. Studies on the genetic and biochemical basis of the disease are continuing.     

Early changes of osteochondrosis in medial femoral condyles from rats

Osteochondrosis developed from the early growing process of articular cartilage at the caudal-central region of the medial femoral condyle in rats. Articular cartilage was thick at the region. Mineralization of the matrix in the thick deep zone was incomplete and major parts remained unmineralized. Cavity formation in the mineralized matrix resulting in osteochondrotic lesions was present in the deep zone at 6 weeks of age and was followed by an appearance of viable chondrocytes around it. Osteochondrotic lesions were present from the age of 10 weeks for females and 12 weeks for males. Cavities were expanded and increased in number, and eosinophilic necrotic foci were additionally seen. These changes were extended throughout the deep zone, and viable chondrocytes were also increased in number. The thick deep zone was retained and had no detectable invasions of blood vessels from the subchondral bone. At 20 weeks of age, necrotic areas containing large clefts were present in the basal layer of the thick deep zone and fibrotic lesions were seen beneath them. In normal cases, invasions of blood vessels were seen in the basal layer of the deep zone and also in the cavities of the cartilage; the deep zone was markedly thinned at 20 weeks of age.     

Relationship of high intensity step-up lighting to bone ash and growth plate closure of the tarso-metatarsus in turkeys

The reduced lameness observed in turkeys reared in a high intensity step-up (HISU) lighting programme as compared to a low intensity step-down (LISD) lighting regimen cannot be explained by differences in the inorganic matrix of the bone, because the proportions of bone ash, bone ash calcium, and bone ash phosphorus did not differ between lighting programmes. At 17 weeks of age, there was a significant difference in the proportion of closed growth plates in males reared on the HISU programme rather than on LISD lighting. These results support the hypothesis that HISU lighting reduces lameness by promoting earlier growth plate closure of long bones.     

Ectopic pulmonary cartilage and bone in domestic fowl

The occurrence and histological appearance of ectopic pulmonary cartilage and bone in domestic fowl was investigated. Its incidence was shown to vary in different strains of birds. The structures may occur in newly hatched chicks and are similarly present in birds maintained on diets containing bonemeal and diets without it. They could not be experimentally induced by bronchial insufflation of fine bone particles. Previous theories of their genesis are discussed and it is concluded that they do not originate from either inhaled dietary bonemeal or disease processes but are probably abnormal embryonic induction of mesenchyme or cartilaginous germ cells displaced from adjacent bronchi.     

Relationship between the concentration of myoglobin and parvalbumin in various types of muscle tissues from chickens

The concentration of parvalbumin was determined in various types of chicken muscle by immunological analysis and was compared with that of myoglobin. Parvalbumin was present specifically in skeletal muscle and absent in cardiac and gizzard muscle; exceptionally, neither parvalbumin nor myoglobin was detected in white breast muscle. The wing and leg red muscles, which had larger amounts of myoglobin, contained smaller quantities of parvalbumin. In these muscles, the concentration of parvalbumin was inversely related to that of myoglobin (correlation coefficient = -0.69). Both myoglobin and parvalbumin were observed in the legs of 18-d-old embryos; the parvalbumin content exceeded that of myoglobin until the birds were 4 to 6 weeks old, but the relationship was reversed thereafter. Myoglobin in gizzard muscle was present in 18-d-old embryos and increased markedly at hatching; it was already present in cardiac muscle at an early embryonic stage, increasing gradually until 14 weeks after hatching.     

Influence of in ovo inoculation with various nutrients and egg size on broiler performance

This study evaluated the influence of inoculation of different nutrients into eggs of 18-d-old broiler embryos. On d 18 of incubation, before transferring, eggs were injected with a solution containing either maltose, a multivitamin supplement, zinc-glycine, glutamine, a mixture containing all these elements, or sodium chloride (control). After hatching, 2,400 male broiler chicks were placed in an experimental broiler house and distributed into 60 floor pens in a completely randomized design comprising a 2 × 6 factorial arrangement of treatments (2 egg weights × 6 solutions), for a total of 12 treatments. Birds and feed consumption were measured weekly. At 42 d of age, 3 birds per replicate pen were randomly selected for processing. Birds derived from heavier eggs had greater hatchability and hatching weight. At 42 d of age, birds from heavier eggs had higher BW, carcass weight, and breast meat weight. The livability of birds derived from heavy eggs was higher at 7 and 14 d of age. The in ovo inoculation of the nutrients to 18-d-old embryos did not influence live performance or carcass traits. The technique of in ovo inoculation of certain nutrients may be used in industrial poultry production, but further studies are required to define the best solutions or mixture of nutrients to be used.     

植酸酶对种鸡生产性能及种蛋孵化性能影响的研究

种鸡在生产条件下，利用植酸酶水解饲料中植酸的原理，观察商品植酸酶替代磷酸氢钙对种鸡生产性能和种蛋孵化性能的影响和评价其实际可应用性。选用２８～３６周龄的肉用黄种鸡（ＮＫ２７１），在饲料中添加３００单位植酸酶替代磷酸氢钙（ＤＣＰ）提供的１．８ｇ无机磷。结果表明：植酸酶使种鸡的产蛋率（＋０．６６％）、日耗料量（－０．７１％）、破蛋率（－９．３％）、不合格种蛋（－４．９５％）、种蛋受精率（＋０．２９％）和１２天活胚率（＋０．７８％）均得到改善，但差异不显著（Ｐ＞０．０５）；而入孵种蛋健雏率（＋１．８９％）、１２天活胚蛋健雏率（＋１．６６％）和残次雏率（－１６．１１％）则优于对照组，差异极显著（Ｐ＜０．０１）。因此，可以认为不仅在种鸡饲料中可用商品植酸酶替代磷酸氢钙，而且对种鸡和种蛋的几乎全部重要生产和繁殖指标，都有不同程度的良好作用。根据目前市场上磷酸氢钙的品质（含氟量）状况，使用植酸酶能够大幅度减轻以至于杜绝由磷酸氢钙导致的氟中毒问题。同时能够预见，使用植酸酶可以大幅度降低排泄物中的含磷量，并能减少对自然环境的污染。可见，植酸酶在种鸡饲料中具有重要的实际应用价值。     

Suppression of IgA synthesis in chickens

Four different protocols were tested for the induction of IgA deficiency in chickens: (I) inoculation of anti-alpha intra-peritoneally (i.p.) on alternate days after hatching up to a period of three weeks; (II) bursectomy within 6 h and at 24 h after hatching; (III) in-ovo injection of anti-alpha on the 17th day of embryonation followed by bursectomy at 24 h of hatch and a single injection of anti-alpha i.p. on the day of hatching; (IV) as in III above but bursectomy within 6 h of hatch, followed by three further injections of anti-alpha on days 3, 10 and 34 after hatching. Treatment (I) produced temporary dysgammaglobulinemia during the period of treatment. Bursectomy at 24 h of hatch rendered 75% of the chicks IgA deficient up to four weeks of age. Early bursectomy within 6 h of hatch resulted in substantial improvement of IgA suppression. Such chicks, when tested at 4, 6 and 10 weeks of age, were found to be 81, 72 and 58.3% IgA deficient, respectively. With treatment (III) all the treated birds were IgA deficient at four weeks of age. However, as the birds grew older, IgA appeared in the serum so that at the age of 12 weeks only 27.3% were deficient. Treatment (IV) completely suppressed the IgA system of 13 out of 14 chickens. These chickens lacked both serum and secretory IgA as well as IgA-containing cells in their intestinal mucosa. Both IgG and IgM continued to be produced.     

Long-term effects of early-life dietary L-carnitine on lymphoid organs and immune responses in Leghorn-type chickens

The long-term effects of supplementing Leghorn-type chickens with dietary L-carnitine after hatching for 4 weeks on growth, lymphoid organ weights, humoral and cell-mediated immune responses were assessed in a 12-week study. A commercial starter feed supplemented with 0 (control), 100 (LC) or 1,000 (HC) mg L-carnitine/kg was offered to day-old ISA Brown cockerels for 4 weeks, then all birds were given a commercial pullet grower feed for another 8 weeks. No differences (p > 0.05) in growth rates, feed intake or feed utilisation efficiency existed among the dietary treatments throughout the study. Compared with control birds, HC-fed birds had a lower (p < 0.05) thymus weight relative to bodyweight (BW) at Week 4, but a higher (p < 0.05) relative thymus weight at Week 12. A higher (p < 0.05) serum primary antibody response to sheep red blood cells (SRBC) in HC-fed birds than in the other two groups was also detected at Week 12. Relative spleen or bursa weights and cutaneous responses of toe webs to phytohaemagglutimin (PHA) (an in vivo indicator of cell-mediated immune responses) did not differ (p > 0.05) among dietary treatments at any time. It is concluded that a short-term supply of dietary L-carnitine to a conventional commercial feed after hatching enhanced subsequent humoral immunity in Leghorn-type chickens. Further study is warranted to confirm such a long-term effect.