Early age thermal conditioning (TC) durably improves resistance of broilers to heat stress and reduces body temperature (Tb). Three experiments on broiler chicks were conducted to evaluate the effects of TC at 5 d of age on Tb variation measured by thermometer between 4 and 7 d of age, under a tropical environment. Because manipulation of chickens to measure Tb with a thermometer may increase Tb, a preliminary experiment on 13 3-to-4-wk-old male broilers compared Tb measured by telemetry to Tb measured in the terminal colon during three successive periods at 22, 33, and 22 degrees C. During heat exposure, Tb rapidly increased by 0.9 degrees C and plateaued over 24 h. During the last period, seven of the broilers rapidly reduced Tb to a plateau lower than the initial Tb, although six broilers exhibited more variable Tb. Measurement by thermometer underestimated on average core Tb by 0.28 degrees C at 22 degrees C and by 0.57 degrees C at 33 degrees C, whereas Tb recorded by telemetry was not affected by manipulation of the chickens. TC reduced Tb 24 h later in the three experiments. Compared to unexposed control chicks (N), 12 h of TC at 40 degrees C did not significantly reduce Tb at 7 d of age, although 24 h did. TC at 38 and 40 degrees C over 24 h significantly reduced Tb variation from 4 to 7 d of age compared to N chicks, whereas 36 degrees C did not. Withdrawing feed from the chicks for 2 h prior to measurement did not significantly reduce Tb at 4 and 7 d of age, but Tb reduction due to TC was greater in fed chicks (0.28 degrees C) than in chicks without feed (0.05 degrees C). Early age thermal conditioning at 38 to 40 degrees C at 5 d of age for 24 h reduced body temperature of 7-d-old male broilers.
Vernix caseosa peritonitis is a rare complication caused by inflammatory response to amniotic fluid spilled into the maternal peritoneal cavity. Most cases occur after cesarean section. We discuss herein two patients, aged 33 and 29 years, who presented with vernix caseosa peritonitis seven to nine days after a cesarean delivery. Laparotomy was performed and it revealed neither uterine rupture nor other surgical emergencies, but cheesy exudates on the serosal surface of all viscera. Appendicectomy was performed. Histopathologic study revealed acute fibrinous serositis and a mixed cellular infiltrate, rich in neutrophils, around fetal desquamated anucleate squamous cells. Patients´ recovery was complete. Clinical diagnosis of vernix caseosa peritonitis should be suspected in patients presenting post-cesarean section with an acute abdomen. Distinctive histopathologic findings allow making the correct diagnosis. Vigilant monitoring after diagnosis is essential as delayed morbidities may appear.
-Early age thermal conditioning (TC) by exposing young chicks to 40o C for 24 hours reduces body temperature (Tb) and improves long-term broiler resistance to heat stress. Three experiments were performed under semi-controlled tropical environmental conditions to evaluate the factors affecting TC efficacy. The addition of infrared bulbs during TC reduced growth and increased water intake compared to gas heaters at similar ambient temperatures (Ta). TC consistently reduced the Tb of chickens at 7 and 40 days of age independently of the heat source (-0.22 o C on average). During heat stress after 40 days of age, significant reduction in mortality was observed in the TC chickens when only gas heaters were used in the second experiment. The use of infrared bulbs during the first week of age never resulted in reduced mortality. The third experiment demonstrated late acclimatization when chickens were exposed to natural climatic conditions (Ta varying daily from 26 to 36 o C) compared to maximal Ta limited to 31 o C by air-conditioning from 30 to 40 days of age. Chickens exposed to natural climatic conditions had lower Tb (-0.16 o C) and resisted heat stress at 38 ± 2 o C at 41 days of age, although 12.6% of the air-conditioned chickens died. The TC effects were maintained on Tb in late acclimatized chickens but no differences in mortality due to TC occurred during heat stress. Inconsistencies between TC experiments arise from an imprecise definition of TC and heat stress conditions, and from the environmental conditions perceived by chickens after TC, which can induce late acclimatization. Persistent reductions in Tb after TC have been consistently measured but these might not be directly responsible for resistance to heat stress. Conversely, of the 525 heat stressed chickens studied during the 3 experiments, 64% of those who had a Tb lower than 40.8 o C at 4 days of age (prior to TC exposure) survived heat stress although only 47% of the chicks having a Tb higher than 40.8 o C at 4 days did. Further research is warranted on the Tb of newly hatched chicks. Résumé -L'acclimatation précoce échoue-t-elle parfois à renforcer la résistance des poulets de chair à un stress thermique chaud ? L'acclimatation précoce (TC) qui consiste à exposer des jeunes poussins à 40 o C pendant 24 heures, fait baisser la température corporelle (Tb) et améliore durablement la résistance des poulets de chair à un coup de chaleur. Trois expériences conduites dans un environnement tropical semi-contrôlé évaluent des facteurs de variation de l'efficacité de TC. Par rapport à une source unique de chaleur au gaz pendant TC, l'adjonction d'ampoules infra rouges a diminué la croissance et augmenté la consommation pour une même température ambiante (Ta). Quelle que soit la source de chaleur, Tb mesurée à 7 et 40 jours d'âge, était toujours diminuée par TC (-0,22 o C en moyenne). TC n'a réduit la mortalité pendant un stress thermique après l'âge de 40 jours que lorsqu'il était appliqué avec des éleveuses à gaz au cours de la seconde expérien...
Summary — Four experiments were conducted with adult cockerels to determine digestibility of amino acids, starch digestibility and true metabolizable energy in ground raw (RJB) and extruded (EJB) jackbean seeds. Three feeding methods were used: ad libitum feeding, dry and wet force feeding.Both RJB and EJB were tested alone or at 3 levels of inclusion, 10, 30
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