Oral and Poster Abstracts

ecause of their lower neutrophil activity. However, other defence
mechanisms, as passive immunity and higher neutrophil count
should be considered. The present results suggest that this increase is
physiologic in cattle. Further studies are necessary to investigate
neutrophil oxidative burst in sick calves.
Key words: zebu, taurine, beef calf, NBT
1040 A Comparison of the Efficacy of Baytril 100 and Bio-Mycin
200 for the Treatment of Bovine Respiratory Disease in
Feedlot Cattle
S. Ives, J. Sears
Bayer Health Care, USA, United States
A study was conducted to evaluate the relative efficacy of Baytril
100 (enrofloxacin) to Bio-Mycin 200 (oxytetracycline) as the initial
therapy in feedlot cattle considered to have a moderate risk for
experiencing respiratory disease. Steers and heifers were procured
from several order buyers, transported to the study site and subjected
to a common processing regimen, which did not include
administration of a metaphylactic antimicrobial. Individual animals
that met enrollment criteria, were treated in pairs, so that one animal
received Baytril 100 (5cc/100 lb body weight) and the other Bio-
Mycin 200 (4.5 cc/100 lb body weight). Animals were penned
according to gender and enrollment treatment, so that at the
completion of the enrollment period, 473 treatment pair groups (946
hd) had been placed on study. Cattle were maintained in 14
enrollment pens (seven per treatment) until cattle were reimplanted,
at which point, pens were combined according to pen size,
enrollment treatment and gender, so that three distinct feeding
groups per treatment were formed. Cattle were kept in their feeding
groups until harvest, at which point, final group weights and carcass
data were obtained. Case fatality rates for animals treated with
Baytril 100 were reduced as compared to animals treated with Biomycin
200 (26.7% vs. 33.3%, respectively; P=0.02). Differences in
carcass parameters were not detected between groups, as cattle that
survived to harvest tended to peform similarly. All cattle enrolled in
this study had a negative financial return, however, the animals
treated intially with Baytril 100 had an economic advantage of
$46.22/head as compared to those treated initially with Bio-mycin
200. The respiratory case fatality rates experienced were
substantially higher than expected for these cattle. The primary
reason was protracted adverse winter weather events occurred during
the conduct of the study which superimposed additional
physiological stress at critical points in the receiving period and
adversely affected these cattle for the remainder of their time in the
feedlot. The results of this study suggest that Baytril 100 may be
more cost effective than a lower cost therapy such as Bio-mycin 200
even in cattle thought to be at a more moderate level of risk for
experiencing BRD.
1041 The Dynamic of Fetal Hemoglobin in Calves of Different
Breeds from Birth to the 180 th Day of Life (age): Influence of
Breeds
M. Caribe Ayres 1 , E. Birgel 2 , AC. Macedo 1 , R. Viana 3 , P. Soares 4 ,
E. Birgel Junior 2
1 Escola de Medicina Veterinária UFBA, Departamento de Patologia
e Clínicas, Salvador, Brazil
2 Faculdade de Medicina Veterinária e Zootecnia, Departamento de
Patologia e Clínicas, Sao Paulo, Brazil
3 Universidade Federal Rural da Amazônia, Departamento de
Medicina Veterinaria, Belém, Brazil
4 Universidade Federla Rural de Pernambuco, Departamento de
Medicina Veterinaria, Recife, Brazil
Fetal and adult hemoglobin of various species behave differently in
their resistance to acids and alkalis, oxygen dissociation curves,
electrophoretic mobility, ultraviolet absorption and in amino acid
composition. Observations to determine the status of postnatal
duration of fetal hemoglobin in the bloodstream have been report in
humans. The hereditary persistence of fetal hemoglobin (HPFH) is a
condition characterized by the continue expression of the fetal
globins in adulthood and this disorders is included as a
hemoglobinopathies. This research was the undertaken to determine
how long the fetal hemoglobin of calves persisted postnatally,
evaluating the influence of breed, in cattle raised in Brazil. For this
study 38 health calves of different breeds (10 Holstein, 10 Jersey, 10
Zebu-Holstein crossbred and eight Gir) were used to follow the
dynamics of the fetal hemoglobin and adult hemoglobin distribution
and the erythrogram changes. To evaluate these variable periodic
blood sampling were carried out with EDTA, from birth to the 180th
day of life. To quantify the fetal hemoglobin and adult hemoglobin a
densitometer method was used and this determination was preceded
by electrophoresis separation of the fetal hemoglobin and the adult
hemoglobin. Red blood cells were washed three times by addition of
0.9% NaCl solution, centrifugation, and removal the supernatant.
The washed cells were then hemolyzed with distilled water and this
solution was frozen at 4 °C and again they were washed by addition
of chloroform and stroma was removed from the supernatant. The
hemoglobin solution was stored at – 80 °C. Analyses were made on
a BioSystem Electrophoreis and the hemoglobin solution was
banded upon on a acetate cellulose and the strips were colored in
Amido Black solution. Statistical methods were used and after
radical transformation of the hemoglobin percents obtained for the
different groups. At the fist day of life most hemoglobin (87%) was
fetal. At the 150 th day the Holstein, Jersey and crossed calves had
only adult hemoglobin while the fetal hemoglobin remained in the
bloodstream if the Gir calves up to 165 th day. The average of the
fetal hemoglobin percents in the birth day was highest in the
Holstein calves. The physiology persistence in the bloodstream in
cattle was influenced by the breed.
Key words: hematology, genetics, fetal hemoglobin, calves,
hemoglobinophaties
1042 Clinical Classification of Diarrhoeas in Calves
P. Cano-Celada, M. Mancera
Universidad Nacional Autónoma de México,Facultad de Medicina
Veterinaria y Zootecnia, Producción Animal:Rumiantes, Mexico, DF.,
Mexico
In this paper we will try to show the importance of the clinical
classification of diarrhoeas, by describing the specific clinical signs,
depending in how long the calf has been sick and the relation with his
dehydration rate. Mechanical diarrhoea with a 0 to 4% non apparent
dehydration, Grade I the new born calf needs 8 to 10% of his live
weigth of milk or calostrum intake every 24 hours, if we administer
more milk we provoke a mechanical diarrhoea, because of the
saturation of nutrient absorption capacity, this provokes an osmotic
change. Acute 5 to 7% GII present diarrhea to 5 to 7 days, with
dehydration. Chronic infectious diarrhoea with 7 to 9% dehydration
rate, G III: In this case diarrhoea persists for 7 to 10 days, with
dehydration, haemoconcentration, vasoconstriction, metabolic
acidosis, respiratory alkalosis, bacteraemia, and toxemia with a 40 °C
fever, tachycardia polipnea, anorexia, depression, very fluid stinky
diarrhoea, adipsia, dry snout, submerged eyes, pale and dry mucosa, the
calf is skinny, and the skin is dry and rough and when you pinch it,
elasticity delays 9 to 15 seconds to return. Severe Diarrhoea and
dehydration from 10 to 12%, G IV. In this cases diarrhoea and
dehydration have been present for more than 15 days, it can be synergic
activity among viruses, bacterias and parasites such as E. coli and
Rotaviruses, clinical signs became worst in a progressive way until
they provoke depression, weakness, total anorexia, fever above 41 °C
because of sepsis and toxemia, tachycardia with arriythmia, polipnea,
pale mucosa, stinky diarrhoea with blood strips or melaena, very
concentrated urine, sphincter weakness, the calf lies down and skin
elasticity when you pinch it returns in 24 to 45 seconds. Serious
diarrhoea with an over 12% dehydration, G V: This a very serius
diarrhoea skin remains together when pinched, we can see severe
dehydration, electrolyte unbalance, immune depression,
metabolic acidosis, respiratory alkalosis, ketosis, hypothermia, uremia,
sepsis, toxemia causing meningitis, shock, seizures and dead, nervous
signs indicate the gravity of the dehydration. Overacute diarrhoea. In
this cases, very susceptible calves die in 72 hours because of extreme
pathogenic aetiologycal agents such as superbacterias, in other cases
the case can be E. coli.
1043 Diarrhoea Treatment and Hydrotherapy in Calves
P. Cano-Celada, A. Olguin y bernal, M. Quiroz-martinez
Universidad Nacional Autónoma de México,Facultad de Medicina
Veterinaria y Zootecnia, Producción Animal:Rumiantes, Mexico, DF.,
Mexico
Calf Physiology, Management and Diseases 243