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Mineral status in blood serum of newborn calves in Assiut Governorate
2009
M. A. Mohammad
The dynamics of some serum mineral concentrations during the first weeks of life of native and crossbred newborn calves in Assiut governorate were investigated. Blood samples of 25 Balady and 25 crossbred (Friesian x native) male calves were investigated. Blood was drawn from calves at 1, 7, 14 and 21 days after parturition. Serum levels of calcium (Ca), phosphorous (P), magnesium (Mg), sodium (Na), chloride (Cl), potassium (K), iron (Fe), Copper (Cu) and zinc (Zn) were monitored. Levels of Ca, P, Fe, Cu and Zn increased (P < 0.05) in relation to age of Balady and crossbred calves when compared by the day 1 of age. In contrast, decreased in concentrations of Na and Cl (P < 0.05) in relation to age of Balady and crossbred calves when compared by the day 1 of age were detected whereas Mg and K values remained unchanged. Native calves had higher (P < 0.05) Ca, P and Fe in the 7th day than crossbred calves whereas Na and Cl were higher (P < 0.05) in native calves than crossbred calves at the first day after birth. Results from this study suggested that breed and age may play an important role in mineral homeostasis during the first weeks of life in the newly borne bovine calves.
Показать больше [+] Меньше [-]Effect of twin vs. single births on gestation length, reproductive performance, dystocia, calf survival rate and culling in Holstein cows
2009
A. S. Mostafa
Data of Holstein dairy cows in a private farm (TEC-DAP) in Al-Fayum Governorate comprising 5815 calving events (80 for twins and 5735 for singles) in the period from January 1997 to April 2008 were used to determine if there was any significant difference between twin and single calving cows in gestation length, reproductive performance, incidence of dystocia, perinatal calf survival and mortality rates and culling rate. Cows giving twins had shorter (p < 0.0001) gestation and more (p < 0.005) days to first heat, first service and days open than cows giving singles. Incidence of dystocia was higher in cows with twins (22.5%) than those with singletons (7.22%). Survival rate of singles was 12.9% greater than that of twins at birth, whereas perinatal mortality rate was 16.25 % (9.37% stillborn & 6.88% dead after birth) for twins and 3.33% (2.06% stillborn & 1.27% dead after birth) for singles. Culling rate was greater in cows producing twins (61.53%) than those with singles (30.73%). Twinning in cattle shortens the length of gestation, impairs subsequent reproductive performance by prolonging postpartum breeding intervals, increases the incidence of dystocia and perinatal calf mortality and increases number of cows to be culled during subsequent lactation. Thus, twinning in dairy cattle is undesirable due to its detrimental effect on cow fertility and health and calf survival. However, these adverse effects can be minimized by preparturient diagnosis of twin pregnancy and timely administration of obstetrical assistance which aids in management of dystocia to facilitate delivery of twin calves and to increase their neonatal survival.
Показать больше [+] Меньше [-]Prospects for controlling trypanosomosis : vector-borne diseases : trypanosomosis
2009
G.A. Vale
The best technical package for the future comprises trypanocidal drugs for temporary relief and the use of insecticide-treated cattle, artificial baits and aerial spraying to attack the vector, to so give more lasting security. Whether this can speed the previously slow progress will depend on overcoming past hindrances to tsetse control : sporadic support, disputes over its desirability, difficulties of sustaining international operations, and poor planning in some instances. The Pan-African Tsetse and Trypanosomiasis Campaign intends to speed the progress but will fail unless it improves its image by breaking its association with the sterile insect technique and quickly executing some cheap and effective operations in large areas. Even then, there could be severe brakes due to Africa's political and financial instability. Overall, the pace of control is likely to increase, but perhaps only a little.
Показать больше [+] Меньше [-]Comparison between urethrostomy and penile resection for treatment of congenital penile urethral dilatation in calves
2009
A. M. Sedeek | H. A. Bakr
A clinical study was conducted under field condition during the period from January 2005 to December 2008 in Beni-Suef province on a total number of 15 calves suffered from congenital penile urethral dilatation at the perineal region. The affection was diagnosed and treated surgically under field condition and treatment included perineal urethrostomy (8 calves) and partial resection of penis including the dilated urethra (7 calves). Results revealed that duration of surgery for urethrostomy was shorter (mean 36.25 minutes) than penile resection (mean 85.71 minutes), bleeding was so extensive in penile resection group than urethrostomy one and cost of surgery was lower for urethrostomy than penile resection but aftercare cost was twice that of penile resection. Complications were higher in urethrostomy group, recovery period was nearly the same in both groups (14.37 and 14.28 days), mean body gain was higher in penile resection group (82 kg) than urethrostomy group (77.14 kg), and both groups considered of low quality animals at market as a result of loss of breeding capability and presence of urine scald. It could be concluded that both techniques are satisfactory but partial penile resection including the dilated urethra is superior to urethrostomy despite the higher cost and invasive surgical procedure.
Показать больше [+] Меньше [-]Comparative histopathology of the lymph nodes, spleen, liver and kidney in experimental ovine trypanosomosis
2009
S.O. Omotainse | V.O. Anosa
The infection of Yankassa rams with three important trypanosome species affecting livestock, namely, Trypanosoma congolense, T. vivax and T. brucei produced both acute and chronic fatal conditions. Chronic infections were induced in the three infections by the application of subcurative doses of diaminazene aceturate (Berenil®). Pathological changes in the infected animals included splenomegaly and hepatomegaly which were more pronounced in acute than in chronic T. congolense infection. However, these changes were more severe in chronic than in acute T. vivax infection. While splenomegaly was more pronounced in chronic T. brucei infection than in acute, hepatomegaly and lymphadenopathy were more severe in acute than in the chronic condition. The increases in size of the spleen, lymph nodes and liver were associated with congestion, increases in cell density related to increased immunological reactions in the spleen and lymph nodes as well as increase in numbers, size and activity of the phagocytic cells in these organs.
Показать больше [+] Меньше [-]Ticks collected from birds in the northern provinces of South Africa, 2004-2006
2009
G. Hasle | I.G. Horak | G. Grieve | H.P. Leinaas | F. Clarke
Approximately 3 000 birds, mainly passerines, caught in mist nets in the northern provinces of South Africa, were examined for ticks. A total of 178 ticks, belonging to 14 species, were recovered from 83 birds of 43 different species. Hyalomma rufipes was the most numerous tick, with 26 larvae and 109 nymphs collected, followed by Amblyomma marmoreum, with 13 larvae and two nymphs. Despite the study being conducted within the distribution range of Amblyomma hebraeum, it was not seen on any passerines, whereas three larger species were infested. The potential for small birds to spread ticks with their associated tick-borne pathogens is discussed.
Показать больше [+] Меньше [-]Veterinary education in Africa : current and future perspectives : animal health management in the 21st century
2009
G.E. Swan | N.P.J. Kriek
Veterinary education commenced in South Africa in 1920 at the Onderstepoort Veterinary Institute in South Africa in association with the Transvaal University College, now the University of Pretoria. Sir Arnold Theiler, Director of Veterinary Research and Education, was the first Dean. Today there are 46 veterinary training institutions in Africa of which 21 are in sub-Saharan Africa.Veterinary services are indispensable to the sustained health and wellbeing of animals and humans, and agricultural economies of countries worldwide. Veterinary education, postgraduate training, and research, and adequate numbers of veterinarians, are essential to satisfy the millennium development goals, the objectives of NEPAD and the African Union, and the agreements regulating international trade.
Показать больше [+] Меньше [-]A brief history of botulism in South Africa : historical overview : Onderstepoort and veterinary research in Africa
2009
C.M. Cameron
When looking back into the history of botulism and contemplating the final understanding of the syndrome and the ultimate solutions, there are four facets that stand out clearly. The first is that much of the solution was guided by astute observations, curious travellers, committed veterinarians and particularly farmers themselves who were able to relate the occurrence of the condition to climatic and grazing conditions. Secondly, there was the identification of the osteophagia and pica syndrome which led to the feeding of bone-meal as a successful mitigating measure as well as the establishment that botulism was not due to a plant poisoning. Thirdly, the solution of the problem depended on the integration of experience and knowledge from diverse disciplines such as soil science, animal behaviour and husbandry, nutrition, botany and ultimately advanced bacteriology and the science of immunology. Finally it required the technical advancement to produce toxoids in large quantities and formulate effective aluminium hydroxide precipitated and oil emulsion vaccines.
Показать больше [+] Меньше [-]Improved management of drugs, hormones and pesticides in Africa : policy and trade issues
2009
E.S. Mitema
Drugs, hormones and pesticides are chemical compounds used for alleviation of various diseases in animals. There are many classes of drugs which have been used and in the case of natural steroid hormones these have been used to increase mass gain by stimulating protein anabolism. Pesticides have been used for many years in the control of ectoparasites which transmit important human and livestock diseases. The purpose of the present article is to review procedures for management of veterinary products to facilitate national and international trade.
Показать больше [+] Меньше [-]Effect of dry period length on reproduction, health and milk production in the subsequent lactation of Holstein cows
2009
M. M. Hussein
A retrospective study was employed to investigate the effect of dry period length on reproduction, incidence of reproductive and metabolic disorders and milk production in Holstein cows belonging to a commercial dairy. Over a 5 year period (2000- 2005), data about reproductive performance, postpartum and metabolic disorders were collected on 1914 multiparous Holstein cows. Out of the obtained data production performance were available only for 793 cows. According to the obtained data the dry period was categorized into 10 groups of different lengths. Reproductive performances including the interval to 1st service, service period, number of inseminations per conception, day’s open, calving interval and percentage of pregnant cows within 100 days in milking (DIM) were recorded as a function of dry period length. The incidence of postpartum reproductive and metabolic disorders included retained fetal membranes (RFM), endometritis, cystic ovarian disease (COD), mastitis, milk fever (MF), ketosis and abomasal displacement were recorded as a function of dry period length. Milk production was also studied in relation to dry period length. Statistical analysis of the obtained data was performed.The most important notifiable results were: cows with dry period less than 28 days showed the best reproductive performance and the highest incidence of abomasal displacement among all groups. In general, the incidence of MF and RFM were higher in short dry period cows, while the incidence of ketosis was higher in cows with long dry period length. A highly significant difference was recorded between daily milk yield of cows with dry period less than 64 days (27.23 kg) and those of cows with dry period > 64 days (25.20 kg).Finally, it is recommended to keep the dry period of 40-60 day lengths to obtain optimum reproduction, health and production of Holstein cows.
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