Departament of Animal Science, School of Agricultural and Veterinary Sciences, São Paulo State University (UNESP), Jaboticabal14883-900, Brazil.
Animal. 2020 Aug;14(S2):s267-s274. doi: 10.1017/S1751731120001457. Epub 2020 Jun 23.
The rate of passage (ROP) in the gastrointestinal tract (GIT) influences the exposure time of food to the digestion and absorption processes. Consequently, ROP affects the efficiency of nutrient utilization and energy from the diet. This study aimed to determine the physiological parameters that characterize the digestive response, such as first appearance time (FAT), ROP, mean retention time (MRT) and transit time (TT) in adult Japanese quail (Coturnix coturnix japonica), and to evaluate the effects of sex, apparent metabolizable energy corrected for nitrogen balance (AMEn) content in the diet and different types of markers on these parameters. In the first trial, we investigated the effects of sex and AMEn level (high- and low-energy diet) on the FAT parameter. Thirty-two male and 32 female Japanese quail were randomly allocated to 8 battery cages and assigned to 4 treatments in a 2 × 2 factorial design with 4 replicates of 4 birds for each treatment. To determine the FAT, ferric oxide (1%) was added to the diet, and the excreta of the quail was monitored until the first appearance of the marker. The results indicated significant differences (P < 0.05) in the FAT between males (100 min) and females (56 min), regardless of the AMEn content. In the second trial, thirty-two 32-week-old female Japanese quail in the laying phase were assigned to four treatments in a 2 × 2 factorial design, in which the main independent variables were type of marker (Cr or Ti) and AMEn level (high- and low-energy diets). In order to determine ROP (ET1%), MRT and TT (ET100%), the markers (0.5%: Cr2O3 and 0.5%: TiO2) were added to the diets, and the excreta were collected for 750 min. The excretion times for 1% (ET1%), 25% (ET25%), 50% (ET50%), 75% (ET75%) and 100% (ET100%) were estimated using cumulative excretion curves. No effect was detected for the AMEn level (P > 0.05); however, the effect of different marker types was significant (P < 0.05). This difference increased with time and ET100% was estimated to occur at 59 min. The ROP was estimated to be 68 min. The TT was estimated to be 540 min using Cr and 599 min using Ti, with an average MRT value of 0930 h. Taken together, our findings support the hypothesis that Japanese quail digestion through the GIT can be dynamic and differ based on sex or marker type.
通过胃肠道（GIT）的通过速率（ROP）会影响食物消化和吸收过程的暴露时间。因此，ROP 会影响营养素的利用效率和饮食中的能量。本研究旨在确定生理参数，这些参数可以描述消化反应，例如成年日本鹌鹑（Coturnix coturnix japonica）的首次出现时间（FAT）、ROP、平均停留时间（MRT）和通过时间（TT），并评估性别、饲料表观代谢能校正氮平衡（AMEn）含量和不同类型标记物对这些参数的影响。在第一次试验中，我们研究了性别和 AMEn 水平（高能量和低能量饲料）对 FAT 参数的影响。32 只雄性和 32 只雌性日本鹌鹑被随机分配到 8 个电池笼中，并按照 2×2 析因设计分为 4 个处理，每个处理有 4 个重复，每个重复有 4 只鸟。为了确定 FAT，饲料中添加了氧化铁（1%），并监测鹌鹑的粪便，直到标记物首次出现。结果表明，无论 AMEn 含量如何，雄性（100 分钟）和雌性（56 分钟）之间的 FAT 存在显著差异（P<0.05）。在第二次试验中，32 只 32 周龄处于产蛋期的雌性日本鹌鹑被分配到 2×2 析因设计的 4 个处理中，其中主要的独立变量是标记物类型（Cr 或 Ti）和 AMEn 水平（高能量和低能量饲料）。为了确定 ROP（ET1%）、MRT 和 TT（ET100%），饲料中添加了标记物（0.5%：Cr2O3 和 0.5%：TiO2），并收集粪便 750 分钟。通过累积排泄曲线估计 1%（ET1%）、25%（ET25%）、50%（ET50%）、75%（ET75%）和 100%（ET100%）的排泄时间。AMEn 水平没有影响（P>0.05）；然而，不同标记物类型的影响是显著的（P<0.05）。这种差异随着时间的推移而增加，ET100%估计在 59 分钟时发生。ROP 估计为 68 分钟。使用 Cr 估计 TT 为 540 分钟，使用 Ti 估计 TT 为 599 分钟，平均 MRT 值为 0930 小时。综上所述，我们的研究结果支持这样一种假设，即日本鹌鹑的胃肠道消化是动态的，并且可能因性别或标记物类型而异。
