Effects of in ovo injection of threonine on hatchability, intestinal morphology, and somatic attributes in Japanese quail (Coturnix japonica)

Figures & data

Table 1. Description of different treatments used for in ovo injection of THR in Japanese quail.

Treatments	Volume (ml)		Additive		Position
	0.05	0.1	Threonine	Serum	In the air sac (5 mm)	Under the air sac (8 mm)
Control (non-injected)	–	–	–	–	–	–
5SIAS^a	✓	–	–	✓	✓	–
5SUAS	✓	–	–	✓	–	✓
1SIAS	–	✓	–	✓	✓	–
1SUAS	–	✓	–	✓	–	✓
5TIAS	✓	–	✓	✓	✓	–
5TUAS	✓	–	✓	✓	–	✓
1TIAS	–	✓	✓	✓	✓	–
1TUAS	–	✓	✓	✓	–	✓

^a5SIAS: injection of 0.05 ml saline (containing 0.9 g salt/litre of distilled water) in the air sac; 5SUAS: injection of 0.05 ml saline under the air sac; 1SIAS: injection of 0.1 ml saline in the air sac; 1SUAS: injection of 0.1 ml saline under the air sac; 5TIAS: injection of 0.05 ml saline containing 5 mg/ml of THR in the air sac; 5TUAS: injection of 0.05 ml saline containing 5 mg/ml of THR under the air sac; 1TIAS: injection of 0.1 ml saline containing 5 mg/ml of THR in the air sac; 1TUAS: injection of 0.1 ml saline containing 5 mg/ml of THR.

Table 2. Effect of in ovo injection of THR on morphological indices of jejunal villi in quail eggs on day of hatch.

Treatments	Villus height (μm)	Villus width (μm)	Villus surface area (μm^2)	Crypt depth (μm)	Villus height/crypt depth	Muscular layer (mm)	Goblet cells (n/villus)
THR 0.05 IAS^d	184.73^bc	40.92	27802^b	29.95	6.54^ab	33.63	7.70^ab
THR 0.05 UAS^e	190.84^a	43.89	31315^a	31.43	7.24^a	35.90	8.50^a
THR 0.1 IAS	182.66^c	40.52	25461^b	34.25	5.86^b	35.05	6.30^c
THR 0.1 UAS	186.08^bc	47.33	25131^b	29.13	5.83^b	34.40	6.20^c
Serum 0.05 IAS	185.97^bc	41.89	28433^ab	30.56	5.80^b	32.63	7.00^bc
Serum 0.05 UAS	187.11^ab	45.89	28236^ab	31.69	6.57^ab	32.08	7.60^ab
Serum 0.1 IAS	182.66^c	51.07	25730^b	31.31	5.87^b	33.87	6.60^bc
Serum 0.1 UAS	181.82^c	44.77	25530^b	31.74	5.81^b	32.26	6.10^c
Control	185.42^bc	43.07	28390^ab	32.83	6.51^ab	33.51	7.10^bc
SEM^f	0.519	1.106	381.718	0.598	0.093	0.434	0.149
P-value	.0002	.416	.0004	.698	.0003	.474	.0003

^a–cValues within a column with different letters differ significantly (P ≤ .05).

^dTHR: threonine, IAS: in the air sac.

^eTHR: threonine, UAS: under the air sac.

^fSEM: standard errors of means (results are given as means (n = 12) for all treatments).

Table 3. Effect of in ovo injection of THR on performance parameters two days after injection (embryonic day 13).

Treatments	BW^d (g)	BW/SEW (%)	YSW (g)	YFBW (g)	DBW (g)	DYFBW (g)
THR 0.05 IAS^e	4.55^b	44.86	1.492^b	2.96^b	1.174	0.593
THR 0.05 UAS^f	4.21^c	44.58	1.499^b	2.71^c	1.182	0.597
THR 0.1 IAS	4.94^a	44.97	1.692^a	3.24^a	1.171	0.592
THR 0.1 UAS	4.95^a	44.68	1.713^a	3.23^a	1.179	0.596
Serum 0.05 IAS	4.54^b	44.87	1.495^b	2.95^b	1.174	0.593
Serum 0.05 UAS	4.21^c	44.59	1.500^b	2.71^c	1.181	0.597
Serum 0.1 IAS	4.94^a	45.01	1.693^a	3.25^a	1.170	0.591
Serum 0.1 UAS	4.96^a	44.72	1.708^a	3.25^a	1.178	0.595
Control	4.22^c	44.55	1.499^b	2.72^c	1.182	0.598
SEM^g	0.028	0.077	0.009	0.020	0.002	0.001
P-value	<.0001	.8159	<.0001	<.0001	.8155	.8243

^a–cMeans within a parameter with no common superscript differ (P ≤ .05).

^dBW = body weight; BW/SEW = BW relative to set egg weight; YSW = yolk sac weight; YFBW = yolk-free BW; DBW = dry BW; DYFBW = dry yolk-free BW.

^eTHR: threonine, IAS: in the air sac.

^fTHR: threonine, UAS: under the air sac.

^gSEM: standard errors of means (results are given as means (n = 12) for all treatments).

Table 4. Effect of in ovo injection of THR on performance parameters at day of hatch.

Treatments	Hatchability (%)	BW^g (g)	BW/SEW (%)	YSW (g)	YFBW (g)	DBW (g)	DYFBW (g)	Intestine (g)	Intestine/BW (%)
THR 0.05 IAS^h	77.08^ab	6.04^b	76.27	0.148^e	5.89^c	2.064	1.258	0.471^bc	7.15^c
THR 0.05 UAS^i	81.82^a	5.45^c	75.80	0.147^e	5.30^d	2.077	1.266	0.506^a	7.93^ab
THR 0.1 IAS	68.75^b	7.85^a	76.45	0.414^d	7.44^ab	2.059	1.255	0.468^bcd	5.50^d
THR 0.1 UAS	68.75^b	7.92^a	75.96	0.427^c	7.49^a	2.072	1.263	0.475^b	5.45^d
Serum 0.05 IAS	72.73^b	6.09^b	76.29	0.148^e	5.94^c	2.064	1.258	0.465^cde	7.09^c
Serum 0.05 UAS	81.82^a	5.49^c	75.81	0.148^e	5.34^d	2.076	1.265	0.459^ef	7.86^b
Serum 0.1 IAS	68.75^b	7.82^a	76.53	0.433^b	7.39^b	2.057	1.254	0.461^def	5.52^d
Serum 0.1 UAS	68.18^b	7.85^a	76.03	0.446^a	7.41^ab	2.070	1.262	0.456^f	5.50^d
Control	83.33^a	5.41^c	75.74	0.146^e	5.27^d	2.079	1.267	0.475^b	7.97^a
SEM^j	1.331	0.095	0.131	0.012	0.083	0.003	0.002	0.001	0.094
P-value	.0007	<.0001	.8159	<.0001	<.0001	.8146	.8131	<.0001	< 0.0001

^a–fMeans within a parameter with no common superscript differ (P ≤ .05).

^gBW = body weight; BW/SEW = BW relative to set egg weight; YSW = yolk sac weight; YFBW = yolk-free BW; DBW = dry BW; DYFBW = dry yolk-free BW; Intestine/BW = intestine weight relative to BW.

^hTHR: threonine, IAS: in the air sac.

ⁱTHR: threonine, UAS: under the air sac.

^jSEM: standard errors of means (results are given as means (n = 12) for all treatments).