Alchemilla vulgaris effects on egg production and quality expressed by heatstressed quail during the late laying period

Abstract

Potential for mitigating effects of heat stress through dietary Alchemilla vulgaris (AV) supplementation during the late laying period of Japanese quail (Coturnix coturnix japonica) were investigated. A 2 x 3 factorial arrangement of environmental temperature (ET) regimes and levels of dietary supplementation with AV (0%, 1%, and 3%) was used in a 75-day experiment. Twenty-five quail were randomly assigned to each treatment with five replicate cages of five birds. The birds were housed in temperature-controlled rooms at 22 ± 2 °C for 24 h/day (TN) or 34 ± 2 °C between 09h00 and 17h00 followed by 22 ± 2 °C for 16 h/day (HS). The interaction of ET and supplement regimes was rarely significant. In HS quail supplemented with 1% AV, egg production was reduced and FCR was increased compared with the other treatments. Dietary AV was found to reduce egg production in TN conditions, but 3% AV supplementation in the HS group prevented decreased egg production and improved FCR. Various indicators of egg quality were significantly affected by supplementation with AV at certain times during the experiment. Most effects of HS on egg quality were manifest in the first 15 days of ET regimes. Although HS significantly decreased eggshell weight until 31-45 days, AV supplementation improved it on the 45th day and then maintained it through the end of the experiment. Thus, AV may mitigate some effects of HS by partially preventing decreased egg production and increased FCR during the late laying period of Japanese quail.

Physiological variables and egg quality from quails (Coturnix coturnix japonica) that received water with increasing levels of NaCl and under different temperatures

“…At the highest temperature, there was a reduction (0.26g) in the albumen weight, which can be justified by the correlation between egg and albumen weight, and egg weights were lower at 32ºC. Silva et al (2017) and Akdemir et al (2019) describe that the height and length of the albumen of quail eggs were affected by heat stress.…”

“…At a temperature of 32ºC, the egg weight decreased by 3.3%, however, this remained within the average and, at this temperature, the physiological variables were higher (Table 1), demonstrating the adaptive capacity of the birds to the hot environment and the thermal amplitude, as occurs in semi-arid regions. Akdemir et al (2019) stated that egg production and weight were reduced in laying quails kept under cyclical heat stress (7h at 34 ± 2ºC), followed by thermal comfort (17h at 22 ± 2ºC).…”

“…A higher percentage of shell in eggs can improve their quality, avoiding breakage during transport and marketing. On the other hand, the increase in the ambient temperature can cause a drop in the quality of the eggshells (Ma et al, 2014), so that the bird increases breathlessness, decreasing the CO 2 in the lungs, which can lead to respiratory alkalosis and results in less absorption of calcium and less efficiency in its use; this results in small and thin-shelled eggs (Akdemir et al, 2019).…”

“…Quails are tolerant of heat conditions (Petrucci et al, 2017;Akdemir, Köseman, & Şeker, 2019) however, as homeothermic birds, they need to maintain constant body temperature with a narrow range of variation (Ribeiro et al, 2016). They are ideal for maximising production when kept within their thermal comfort zone, which for adult quails should be temperatures between 18 and 26ºC and relative humidity between 50 and 70% (S. M. Santos et al, 2014;El-Tarabany, 2016;Silva et al, 2017).…”

“…Quails raised under heat stress conditions modify their ingestive behaviour and trigger heat loss mechanisms, which can increase respiratory and heart rate, as well as cloacal and body surface temperature (Souza et al, 2013;Ribeiro et al, 2016;Rodrigues, Furtado, Costa, Nascimento, & Cardoso, 2016), affecting animal welfare (T. C. Santos, Gates, Tinôco, Zolnier, & Baêta, 2017) by compromising feed intake, assimilation, and metabolism, and causing a decrease in egg production, weight, and quality (Silva et al, 2017;Akdemir et al, 2019).…”