Tibiotarsal rotation in ostrich chicks is a serious problem that accounts for considerable financial loss to ostrich farmers. Serum- and bone-mineral analyses of 20 ostrich chicks with tibiotarsal rotation were compared with serum- and bone-mineral analyses of eight normal ostrich chicks of comparable age, sex and body mass, and raised under identical conditions. The serum-zinc values were significantly higher and the bone-calcium and phosphorus values significantly lower in the affected group than in the group of normal ostrich chicks. The results indicated poor mineralization of bone with subsequent reactive osteoid formation.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. 
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Bezuidenhout, A.J. (Abraham Johannes), 1942-

Burger, W.P.

Reyers, Fred

Soley, John Thomson

The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. 
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.Tibiotarsal rotation in ostrich chicks is a serious problem that accounts for considerable financial loss to ostrich farmers. Serum- and bone-mineral analyses of 20 ostrich chicks with tibiotarsal rotation were compared with serum- and bone-mineral analyses of eight normal ostrich chicks of comparable age, sex and body mass, and raised under identical conditions. The serum-zinc values were significantly higher and the bone-calcium and phosphorus values significantly lower in the affected group than in the group of normal ostrich chicks. The results indicated poor mineralization of bone with subsequent reactive osteoid formation.mn201

UPSpace at the University of Pretoria

' Onderstepoort Journal of Veterinary Research, 61 :203-206 (1994) Serum- and bone-mineral status of ostriches with tibiotarsal rotation A.J. BEZUIDENHOUT1, W.P. BURGER2, F. REYERS3 and J.T. SOLEY1 II ABSTRACT BEZUIDENHOUT, A.J., BURGER, W.P., REYERS, F. & SOLEY, J.T. 1994. Serum- and bone-mineral status of ostriches with tibiotarsal rotation. Onderstepoort Journal of Veterinary Research, 61 :203- 206 Tibiotarsal rotation in ostrich chicks is a serious problem that accounts for considerable financial loss to ostrich farmers. Serum- and bone-mineral analyses of 20 ostrich chicks with tibiotarsal rotation were compared with serum- and bone-mineral analyses of eight normal ostrich chicks of comparable age, sex and body mass, and raised under identical conditions. The serum-zinc values were significantly higher and the bone-calcium and phosphorus values significantly lower in the affected group than in the group of normal ostrich chicks. The results indicated poor mineralization of bone with subsequent reactive osteoid formation. INTRODUCTION The twisted- or rotated-leg syndrome in ostrich chicks is well documented. Bezuidenhout & Burger (1993) reviewed the relevant literature and determined the incidence of proximal and distal tibiotarsal rotation in ostrich chicks raised at the Oudtshoorn Experi-mental Farm during the 1991- 1992 and 1992- 1993 breeding seasons. The greatest incidence of the condition is seen in 4-8-week-old birds. The pathogenesis of the condition is not entirely understood. Aetiology indicates that nutrition, strain, housing, sex, exercise and growth rate are factors involved. 1 Department of Anatomy, Faculty of Veterinary Science, Uni-versity of Pretoria, Private Bag X04, Onderstepoort, 011 0 South Africa 2 Ostrich Research Centre, P.O. Box241, Oudtshoorn, 0110 South Africa 3 Department of Medicine, Faculty of Veterinary Science, Uni-versity of Pretoria, Private Bag X04, Onderstepoort, 0110 South Africa Received 7 July 1994- Editor There is, however, no evidence that the condition is congenital or that inflammation plays a role. Some blood-chemical and electrolyte concentrations in 1-3-year-old ostriches kept under semi-extensive condi-tions were determined by Van Heerden, Dauth, Jar-vis, Keffen, Denny, Dreyer & Kriek (1985), while Levy, Perelman, Waner, Van Grevenbroek, Van Creveld & Yagil (1989) determined some reference blood-chemical values in 1- 72-month-old ostriches kept un-der intensive conditions. Palomeque, Pinto & Viscor (1991) determined haematologic and blood-chemistry values of Masai ostriches at five and 17 months of age under zoo conditions. Furthermore, Gandini, Burroughs & Ebedes (1986) raised ostrich chicks on four different dietary regimes to study body-mass gain and found that some of the chicks developed tibiotarsal rotation. Flieg (1973) stu-died nutritional problems in young ratites and, based on his findings, formulated the Falstaff diet for young ratites. The present study was undertaken to deter-mine the serum- and bone-mineral status of ostrich chicks with tibiotarsal rotation and to compare the values with those of ostrich chicks without limb de-formities, raised under identical conditions. 203 Serum- and bone-mineral status of ostriches MATERIALS AND METHODS All materials for the study were obtained from the Oudtshoorn Experimental Farm, Oudtshoorn. At hatch-ing, all the ostrich chicks were identified and marked by means of a numbered wing tag. The chicks were kept in mixed groups and raised under identical con-ditions. Twenty chicks that developed tibiotarsal rota-tion between the ages of 4 and 8 weeks, were ran-domly selected for the study. Each ostrich chick was identified, its body mass was determined and a blood sample was collected. Five millilitres of serum were obtained by centrifuge separation of the blood, and the serum sample was identified by the wing-tag number. The bird was then culled, its sex was de-termined and both hind limbs were removed. All soft tissue was removed from the bones and the limbs were identified by means of the numbered wing tag. The serum and bones were subsequently frozen at - 2oac until such time as the mineral analyses could be done. Eight ostrich chicks from the same group as the affected chicks were selected as controls. Al-though the controls were of comparable age, body mass and sex, and had been raised together with the affected birds, sharing the same camp, feed and water, they did not develop tibiotarsal rotation. They were processed in the same way as the affected birds. A 2 kg aliquot of the feed on which the chicks were raised was taken for mineral analysis. The serum and bone samples of both groups were analyzed for calcium (Ca) , phosphorus (P) , magne-sium (Mg), manganese (Mn), zinc (Zn), and copper (Cu), by the Allerton Regional Laboratory in Pieter-maritzburg, Natal. The serum samples were ana-lyzed in a Phillips PU 9100 Atomic Absorption Data Station, while the feed and bone analyses were done by incineration and spectrometry. The results of the analyses were statistically tested by one-way analy-sis of variance (ANOVA) and the "Statsgraphics" (Manugistics, Inc. 2115 East Jefferson St, Rockville, Maryland, 20852, USA) statistical analysis programme was used. The difference between the two groups was tested by the F-ratio test. A significance level of P < 0,05 was used to determine whether the re-sult could be attributed to chance. Feed-mineral val-ues were compared with the values suggested for ratites by Flieg (1973) and Gandini eta/. (1986) . RESULTS The mean value and range of the serum-mineral anal-yses for affected and normal ostrich chicks are rep-resented in Table 1 and the mean value and range of the bone-mineral analysis for the two groups are given in Table 2. The mineral analysis of the feed is represented and compared with the values sug-gested by Flieg (1973) and Gandini eta/. (1986) in 204 TABLE 1 Mean and range of the serum-mineral content Minerals Normal birds Affected birds Ca mmoi/Q 2,276 (1 ,60- 2,86) 2,246 (1 ,90- 2,80) P mmoi/Q 1,975 (1 ,47- 3,42) 2,195 (1 '13- 3,56) Mg mmoi/Q 0,8744 (0,61 - 0,99) 0,8563 (0,72-1 ,33) Mn rtmoi/Q 0,3672 (0,32- 0,67) 0,4638 (0,05-0,87) Zn rtmoi/Q 10,608 (6,28-19,16) 18,405 (7,98-36,13) Cu rtmoi/Q 4,236 (1 ,98-£,04) 3,84 (1,79-9,39) TABLE 2 Mean and range of the bone-mineral content expressed as percentage of bone Minerals Normal birds Affected birds Ca 22,12 (20,029-23,977) 20,09 (17,823--22,463) p 9,124 (8,384-9,991 ) 8,537 (7,567-9,488) Mg 0,435 (0,383- 0,509) 0,435 (0,370-0,489) Mn < 0,000 (0,000-0,001) < 0,000 (< 0,000-0,001) Zn 0,02147 (0,016-0,024) 0,0201 (0,01 8-0,024) Cu < 0,0000 (< 0,000-0,001) < 0,000 (< 0,000-0,001) TABLE 3 Comparison of the feed-mineral content of the Flagstaff ratite feed of Flieg (1973), the feed of Gandini et a!. (1986) and the feed used at the Oudtshoorn Experi-mental Farm for the present study Minerals Flieg (1973) Gandini et at. (1986) Present study Ca % 1,78 1,4 1,86 P % 0,67 0,7 0,8 Mg % 0,256 0,2-0,24 0,20 Mn ppm 120 90-91,5 20 Zn ppm 104 75,6-78 54 Cu ppm 17,3 10,7- 11 7 TABLE 4 One-way analysis of variance (ANOVA) Constituent M.S. group M.S. error F-ratio p Blood Ca 0,00476 0,27253 0,017 0,8974 p 0,26806 0,29324 0,914 0,3587 Mg 0,00183 0,02076 0,088 0,7720 Mn 0,05161 0,03392 1,521 0,2294 z 336,740 33,9400 9,923 0,0043 Cu 0,86901 4,4911 0 0,1930 0,6686 Bone Ca 21,1669 2,12770 9,948 0,0043 p 1,76140 0,36140 4,874 0,0371 Mg 0,0000001 0,00150 0,000 0,9953 Mn 0,00000 0,00000 1,198 0,2846 z 0,00001 0,00001 1,731 0,2007 Table 3. The statistical analyses of the serum- and bone-mineral values are given in Table 4. The analy-sis indicated that serum-Zn levels were significantly (a significance-probability level of P < 0,05) elevated in the affected birds as compared with normal birds, and that their bone-Ca and -P levels were significant-ly (P < 0,05) lower as compared with normal ostrich chicks. Analysis of the feed indicated a P level slight-ly above that suggested for broilers and a Mn level of half the minimum suggested value for broilers. No difference in the serum- or bone-mineral analysis of male and female chicks between and within groups could be demonstrated. DISCUSSION During normal long-bone development, which is characterized by endochondral, sub-periosteal and endosteal ossification, the osteoid matrix is laid down by osteoblasts and is subsequently mineralized to form bone. Various microminerals, including Zn, func-tion as co-enzymes in the process of osteoid-matrix formation, while hormones, including those of the parathyroid gland, play an important role in the min-eralization of the osteoid. Deficient formation or poor mineralization of the osteoid matrix will lead to defi-cient bone formation and subsequent bone abnor-malities. When the mineral content of the feed used in the present study was compared with the mineral content of the Falstaff ratite feed of Flieg (1973) and with the diets used by Gandini eta/. (1986), it was found that the Ca, P and Mg levels were about the same. The Mn, Cu and Zn contents, however, were substantially lower. Van Heerden et a/. (1985) and Levy et a/. (1989) established normal serum-P and -Ca levels for os-triches of various ages and under varying manage-ment systems. In the present study the serum-Ca and -P levels of both affected and normal birds were found to be within the normal range reported by the previ-ous two groups of researchers. This was to be ex-pected as blood-Ca and -P levels are maintained at the cost of other tissues. Gandini eta/. (1986) raised 20 ostrich chicks on four different rations and found that five chicks developed enlarged hocks and bowing of the tarsometatarsus at 6- 7 weeks of age. Radio-graphically, the chicks showed widening and poor mineralization of the metaphysis and epiphyseal plate. The birds improved and showed increased minerali-zation after the administration of calcium borogluco-nate. Dietary deficiency in Ca was thus shown to be the cause of the bone abnormalities. In the present study the Ca and P content of the feed was found to be within the range suggested by Flieg (1973) and Gandini eta/. (1986) and the serum-Ca and -P levels of affected and normal birds were within the normal A.J. BEZUIDENHOUT eta!. limits established by Van Heerden eta/. (1985) and Levy eta/. (1989). However, the bone Ca and P of chicks with tibiotarsal rotation was significantly (P < 0,05) lower, compared with the values in normal chicks, despite the fact that they were raised on the same diet and that their serum-Ca and -P levels were normal. Normal bone contains a significant amount of Zn. In the present study, the serum-Zn levels of affected birds were significantly (P < 0,05) elevated when com-pared with those of unaffected birds, despite the fact that both groups received the same food and that the Zn content of the feed was low. There was, how-ever, no difference between the bone-Zn content of affected and normal birds. This can possibly be ex-plained as an attempt by the body to produce more bone (osteoid or bone matrix) in response to the bone abnormality (poor mineralization) in the affect-ed birds. These results would appear to indicate poor mineral-ization of bone in the affected birds. The factors re-sponsible for promoting poor bone mineralization in the affected birds were not determined in the present investigation. The results of the present study indicate that the problem of tibiotarsal rotation is very complex and needs to be investigated further. An essential part of future research must be the establishing of normal serum-, bone- and other tissue- (e.g. liver) -mineral values of ostriches at various ages and stages of growth. All minerals involved in normal bone devel-opment and growth should be investigated and base-line values should be determined for all the areas where ostrich farming is undertaken. Other possible fields of investigation are the effect of rapid growth, age, sex, internal parasites, breeding season and genetics on the absorption and metabolism of the various minerals involved in bone formation. ACKNOWLEDGEMENTS The authors would like to thank Dr W. Schultheis for advice. REFERENCES BEZUIDENHOUT, A.J . & BURGER, W.P. 1993. The incidence of tibiotarsal rotation in the ostrich (Struthio came/us). Journal of the South African Veterinary Association , 64:159- 161 . FLIEG, G.M. 1973. Nutritional problems in young ralites. Inter-national Zoo Yearbook, 13:158- 163. GANDINI, G.C.M., BURROUGHS, R.E.J. & EBEDES, H. 1986. Preliminary investigation into the nutrition of ostrich chicks (Struthio came/us) under intensive conditions. Journal of the South African Veterinary Association, 57:39-42. LEVY, A. , PERELMAN, B. , WANER,T., VAN GREVENBROEK, M., VAN CREVELD, C. & YAGIL, R. 1989. Reference blood 205 Serum- and bone-mineral status of ostriches chemical values in ostriches (Struthio came/us). American Jour-nal of Veterinary Research, 50:1548-1550. PALOMEQUE, J. , PINTO, D. & VISCOR, G. 1991. Hematologic and blood chemistry values of the Masai ostrich (Struthio cam-e/us). Journal of Wildlife Diseases, 27:34-40. 206 VAN HEERDEN, J. , DAUTH, J., JARVIS, M.J.F., KEFFEN, R.H. , DENNY, J.E.F.M., DREYER, M.J. & KRIEK, N.P.J. 1985. Blood chemical and electrolyte concentrations in the ostrich Struthio came/us. Journal of the South African Veterinary Association, 56:75-79. 

Serum- and bone-mineral status of ostriches with tibiotarsal rotation

https://repository.up.ac.za/bitstream/2263/32745/1/26bezuidenhout1994.pdf

Serum- and bone-mineral status of ostriches with tibiotarsal rotation

Abstract

Similar works

Full text

Available Versions

UPSpace at the University of Pretoria