RESUMEN

Abomasal hypomotility is one of the important causes of neonatal mortality in small ruminants. Various pharmaceutical agents have been studied to address this problem in large ruminants. The aim of this study was to determine the effect of parenteral administration of tylosin and ivermectin on abomasal emptying rate in neonatal suckling lambs. Abomasal emptying rate was assessed using nuclear scintigraphic method in 10 healthy female Iranian fat tailed Ghezel lambs. Each lamb was tested three times, once as a control (1 ml of saline 0.9%, IM) and twice after the injection of tylosin (17.6 mg/kg, IM) and ivermectin (200 µg/kg, SC) in a crossover study. Based on radiopharmaceutical counts, remnant activity in abomasums at 90 min were 48.3 ± 3.5, 45.6 ± 7.5 and 41.6 ± 2.9% in control, tylosin and ivermectin groups, respectively. Administration of tylosin (p = 0.049) and ivermectin (p = 0.045) to lambs, significantly caused faster abomasal emptying rate compared to control. Evaluating the ROIs revealed that the half emptying time (T1/2) in control, tylosin and ivermectin groups were 67.1 ± 8.6, 62.6 ± 14.2 and 54.3 ± 9.9 min, respectively. These difference between all groups, statistically were significant (p = 0.026). However, the clinical efficacy of abomasal emptying rate facilitating by tylosin or ivermectin administration in lambs remains to be determined.

Asunto(s)

RESUMEN

This study investigated abomasal luminal parameters in healthy and diarrheic calves by using a wireless ambulatory capsule (WAC). The acetaminophen absorption test (APAT) was used to determine abomasal emptying rate. Four healthy and five diarrheic female Holstein-Friesian calves (age < 14 days) were included in the study. For APAT, calves were fed 2 L of milk replacer containing 50 mg acetaminophen/kg body weight, and blood samples were taken during a 12-h period afterward. Concomitantly, a WAC in the abomasum continuously measured luminal pH, pressure, and temperature. Five hours post suckling, intraluminal temperature was significantly higher in diarrheic calves than in healthy calves. Abomasal pH and pressure were not significantly different, but intraluminal pressure was always numerically lower in diarrheic calves. During APAT no significant differences in maximum acetaminophen concentrations (Cmax) and time to reach maximum acetaminophen concentration (Tmax) were observed. Nonlinear regression findings revealed a longer acetaminophen half-time (AAP t1/2) in diarrheic calves compared to healthy calves [564 ± 96 min vs. 393 ± 84 min, respectively; P = 0.04] and lower area under the concentration curve values (e.g., 60 min postprandial AUC60 681 ± 244 (µg∙min)/mL vs. 1064 ± 23 (µg∙min)/mL, respectively; P = 0.04). In conclusion, abomasal luminal conditions were different between diarrheic and healthy calves. Significant differences in APAT reflected a delay in abomasal emptying in diarrheic calves. Impaired abomasal movement may induce enhanced bacterial fermentation processes as indicated by a higher abomasal temperature in diarrheic calves, which should be considered in management of their feeding.

RESUMEN

Diarrhoea is a condition with tremendous impact on calf health. Infectious agents play a dominant role; however, non-infective factors may also contribute to pathogenesis of diarrhoea. One factor, the abomasal emptying rate, is mainly influenced by the composition of feed. The aim of the study was to assess the influence of different protein sources in milk replacers on abomasal emptying rate and clinical parameters. The effect of increasing age of the calves on abomasal emptying was also evaluated. The study compared abomasal emptying rates and clinical parameters in calves, which were fed either milk replacer containing only whey protein or one which partially contained wheat protein. Abomasal emptying rate was estimated by ultrasonography. Ten calves were used in the study over 18 days, and each calf was fed 3 periods of 3 days length using different milk replacers in an alternating crossover design. The abomasum was emptied significantly faster when the wheat protein containing milk replacer was fed (half-emptying time wheat protein 49.1 ± 4.1 min, half-emptying time milk protein 59.1 ± 7.4 min); however, clinical parameters and weight gain did not differ between the feeding regimes. Age did not significantly influence abomasal emptying rate. As milk replacers containing wheat proteins increased abomasal emptying rate, they may have a higher potential to initiate diarrhoea, especially if high volumes are fed. Thus, the feeding regimes are likely to be even more important when such milk replacers are used.

Asunto(s)