Fig 1.
The age of the birds (days) is indicated on the horizontal axis. All birds received the basal diet between 85 and 100 days of age. From 100 to 128 days of age, females were subjected to chronic dietary supplementation (S). Five diets (N = 50; n = 10) were administrated (indicated with boxes): two controls (BASAL and VEHICLE) and three increasing doses of THY (THY2, THY4 and THY6, corresponding to 2, 4 and 6.25 g of THY/kg feed, respectively). Vertical dotted lines indicate changes in the diet of each experimental group. Once finished the supplementation period, half of the quail were slaughtered for histological analysis (Slaughter 1). The other half of the quail was subjected to a post-supplementation period of 21 days (pS) during which the basal diet was reestablished. Finished de pS period, the remaining birds were slaughtered (Slaughter 2). To assess dynamics five sample points were defined: one initial sample point; three sample points along the S period and one at the end of the pS period.
Fig 2.
Thymol concentration in quail egg yolk and droppings.
Mean ± SEM of thymol concentration (ng/g) in the (A) egg yolk and (B) droppings from females fed on diets with 2, 4, and 6.25 g of thymol/kg of feed (THY2, THY4 and THY6, respectively) at 2, 9, 16, and 26 days of the supplementation period (S) and after 17 days of supplement withdrawal (pS). Arrow pointing down indicates the end of the S period. In Fig 2A different letters (a, b, c) and numbers (1, 2, 3) indicate statistical differences for the diet supplied and time of sampling, respectively. In Fig 2B different letters (a, b, c, d, e, f) indicate statistical differences for the interaction. The same 15 females (5 per THY supplemented diet) were sampled on each of the five sample points (75 eggs and 45 droppings samples total). BASAL and VEHICLE samples were evaluated at the beginning and end of the day at each sample point to assure the absence of THY.
Table 1.
Statistical information corresponding to the effects of the diet supplied, time of sampling and their interaction on thymol (THY) concentration in quail egg yolk and droppings and concentration of egg yolk total fatty acids.
Fig 3.
Concentration of saturated, monounsaturated and polyunsaturated fatty acids of quail egg yolk.
Mean ± SEM of content (g/100 g FAME) of (A) saturated (myristic + pentadecanoic + palmitic + stearic acids), (B) monounsaturated (palmitoleic + oleic acids) and (C) polyunsaturated (linoleic + linolenic + arachidonic + docosahexaenoic + eicosapentaenoic + docosapentaenoic acids) fatty acids of quail egg yolk laid by females fed on the control diets (BASAL and VEHICLE) or supplemented with 2, 4, and 6.25 g of thymol/kg of feed (THY2, THY4 and THY6, respectively) at 0, 7, 14, and 28 days of the supplementation period (S) and after 21 days of supplement withdrawal (pS). Arrow pointing down indicates the end of the S period. Brackets refer to measurements within a time of sampling. Different letters (a, b, c, d) indicate statistical differences. The same 25 females (5 per diet supplied) were analyzed on each of the five sample points (125 eggs total).
Fig 4.
Concentration of saturated fatty acids of quail egg yolk.
Mean ± SEM of content (g/100 g FAME) of (A) palmitic (16:0) and (B) stearic acids (18:0) of quail egg yolk laid by females fed on the control diets (BASAL and VEHICLE) or supplemented with 2, 4, and 6.25 g of thymol/kg of feed (THY2, THY4 and THY6, respectively) at 0, 7, 14, and 28 days of the supplementation period (S) and after 21 days of supplement withdrawal (pS). Arrow pointing down indicates the end of the S period. Different letters (a, b, c) indicate statistical differences. Brackets refer to measurements within a time of sampling. The same 25 females (5 per diet supplied) were analyzed on each of the five sample points (125 eggs total).
Fig 5.
Concentration of monounsaturated fatty acids of quail egg yolk.
Mean ± SEM of content (g/100 g FAME) of (A) palmitoleic (16:1) and (B) oleic acids (18:1) of quail egg yolk laid by females fed on the control diets (BASAL and VEHICLE) or supplemented with 2, 4, and 6.25 g of thymol/kg of feed (THY2, THY4 and THY6, respectively) at 0, 7, 14, and 28 days of the supplementation period (S) and after 21 days of supplement withdrawal (pS). Arrow pointing down indicates the end of the S period. Different letters (a, b) indicate statistical differences. Brackets refer to measurements within a time of sampling. The same 25 females (5 per diet supplied) were analyzed on each of the five sample points (125 eggs total).
Fig 6.
Concentration polyunsaturated fatty acids of quail egg yolk.
Mean ± SEM of content (g/100 g FAME) of (A) linoleic (18:2), (B) linolenic (18:3), (C) arachidonic (20:4), (D) docosahexaenoic (22:6), (E) eicosapentaenoic (20:5) and (F) docosapentaenoic (22:5) acids of quail egg yolk laid by females fed on the control diets (BASAL and VEHICLE) or supplemented with 2, 4, and 6.25 g of thymol/kg of feed (THY2, THY4 and THY6, respectively) at 0, 7, 14, and 28 days of the supplementation period (S) and after 21 days of supplement withdrawal (pS). Arrow pointing down indicates the end of the S period. Different letters (a, b) indicate statistical differences. Brackets refer to measurements within a time of sampling. The same 25 females (5 per diet supplied) were analyzed on each of the five sample points (125 eggs total).
Table 2.
Overall mean values (± SEM) and statistical information regarding performance related variables from female quail fed with control diets or supplemented with thymol (Diet supplied) over five time points (Time of sampling).
Fig 7.
Example photomicrographs of quail liver 40X.
(A) Normal liver, (B) liver with steatosis or fatty degeneration, (C) vascular congestion and dilatation of sinusoids, and (D) oval cell focus. Arrows point to representative examples of the corresponding alteration in the photograph.
Fig 8.
Frequency of histopathological alterations registered in all livers analyzed.
The reaction pattern (RP) to which the alterations correspond is indicated with different intensity of gray and a circular label: RP1 (circulatory disturbances), RP2 (regressive changes), RP3 (progressive changes), RP4 (inflammation) (n = 5; N = 45, only 5 birds from the basal diet were studied).
Table 3.
Overall mean values (± SEM) and statistical information regarding liver histopathological indices by reaction pattern and total liver index for female quail fed with control diets or supplemented with thymol (Diet supplied) slaughtered at two time points (Slaughter batch).