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This study was conducted in two steps to determine the effects of in ovo injection of zinc acetate (ZAC) on some gene expression associated with embryonic growth and development, and with growth and carcass characteristics of the resultant chicks. In the first step the effect of in ovo injection of ZAC on the expression of insulin-like growth factors (IGFs:IGF-I and IGF-I), myogenic regulatory factors (MRFs) and metallothionein (MT) genes was examined, and in the step two, the associations between genes expression with fertility, embryonic mortality, hatchability, body weight (BW) and relative organ weight on day of hatch, and body weight (BW) and feed conversion ratio (FCR) a week after hatching were investigated. Seven hundred twenty fertile eggs (n=720) were randomly divided into 4 treatment groups consisted of: 1) noninjected (NI) group, 2) sham group (group injected with deionized water (DW)), and 3) and 4) groups injected with 3.64 and 5.23 M ZAC, respectively. On day 3 of incubation the eggs were injected with 50 µL of each treatment into the albumen. On day 5 of the incubation and on hatch day, liver and breast muscle of the chicks were removed and immediately stored at -80 °C until RNA extraction and real time-PCR analysis. In ovo ZAC injection increased myogenic differentiation factor both in embryo and breast muscle. MT mRNA expression was also increased by ZAC injection. Hatchability was lower in ZAC groups and early embryonic mortality was higher in sham control (SHC) and ZAC groups. Injection of ZAC improved both BW and FCR during the first week of rearing, and increased the relative weights of liver and breast muscle. In conclusion, in ovo injection of ZAC increased some of gene expressions of tissues and BW7 during the first week, but decreased hatchability. Hence, lower doses of ZAC are recommended to use in further experiments. [ABSTRACT FROM AUTHOR]

Present preliminary scientific trial was designed to investigate of microwave effects on Japanese quails as an animal model. Thirty six three days-old quail chicks were randomly divided into 3 experimental groups and received: A) un-treated tap water, B) tap water boiled by electrical heater and then cooled and C) tap water treated by microwave oven and then cooled. The whole experimental period was 40 days. During the experiment body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) were measured. At the end of the study, carcass, liver, spleen and bursa of fabricius weighed and small intestinal length, blood hemoglobin and hematocrit, small intestinal villus height and crypt depth were measured. The lowest body weight gain was observed in group C (P<0.01). Haemoglobin and hematocrit values of group C were less than group A (P>0.01). Carcass, liver, spleen and bursa of fabricius weights and small intestinal length were the lowest in group C (P<0.01). Crypt depth of group C was higher than the group A (P<0.01). Qualitative observations of reproductive organs such as: ovaries, oviducts, follicles and testis of group C showed less growth in comparison with the other groups. Treatment of drinking water by microwave had side effects on Japanese quails. Tease effects were not the simple effects of boiling since heat-boiled drank quails did not show such effects. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine the effect of PGF2α treatment 14 d before the initiation of a G6G or G7G (PGF2α, 2 d, GnRH, 6 or 7 d, Ovsynch) protocol on ovarian response, synchronization protocol on ovarian response, progesterone (P4) concentration, pregnancy per AI (P/AI), and pregnancy loss in multiparous Holstein cows. Cows (3.6 ± 1.1 lactations and yielding >30 kg/d of milk) were randomly assigned to 1 of 4 timed artificial insemination (TAI) protocols: 1) G6G (n = 240), one injection of PGF2α, GnRH 2 d later and a 7-d Ovsynch protocol (GnRH, 7 d, PGF2α, 56 h, GnRH 16 h TAI) was initiated 6 d later; 2) PG6G (n = 250), PGF2α 14 d before the initiation of the G6G protocol; 3) G7G (n = 200), one injection of PGF2α, GnRH 2 d later, and a 7-d Ovsynch protocol initiated 7 d later; and (4) PG7G (n = 200), a PGF2α injection 14 d before the initiation of the G7G protocol. Blood samples from a subset of 269 cows were collected at the times of first and second GnRH, and PGF2α of the Ovsynch protocol to measure P4. Ultrasound examinations were performed to evaluate ovarian response to GnRH and PGF2α of Ovsynch, and to determine pregnancy status at 32 and 60 d after TAI. The proportion of cows with high (≥1 ng/mL) P4 at first GnRH of Ovsynch was greater for PG6G and PG7G compared with G6G and G7G groups (combined 79.7 vs. 59.3%). In addition, mean (±SEM) plasma P4 concentration (ng/mL) at PGF2α of Ovsynch was also greater in PG6G (6.5 ± 0.2) and PG7G (6.7 ± 0.3) compared with G6G (5.1 ± 0.2) and G7G (5.0 ± 0.2). Cows given PGF2α 14 d before initiating a G6G or a G7G TAI (PG6G and PG7G) tended to have a greater P/AI at 32 d compared with those cows not receiving PGF2α (G6G and G7G). However, P/AI at 60 d was greater in cows subjected to PG6G and PG7G protocols (31.1 vs. 39.2%), with a lower pregnancy loss between 32 and 60 d (11.65 vs. 19.7%). In summary, administration of PGF2α 14 d before initiating a G6G or a G7G TAI protocol increased P4 concentrations before artificial insemination and late embryonic/early fetal survival in multiparous Holstein cows. [ABSTRACT FROM AUTHOR]

Genistein (GEN), a soybean isoflavone, is structurally and functionally similar to endogenous estrogen; therefore, it has the potential to enhance estradiol properties. This study aimed to evaluate the effects of GEN on the reproductive performance and bone status of laying hens. In total, 80 Hy-line W-36 (40 weeks old, the late stage of egg production cycle) with an initial body weight of 1,230&plusmn;15.8 g (Mean&plusmn;S.E.M), similar egg production, and egg weight were randomly assigned into two groups with 10 replicates and 4 birds in each replicate (40 laying hens per group). Laying hen diets had 0 (control) and 20 mg/kg GEN (white powder, Sichuan Guanghan co. Ltd., purity of 98.5%) for 6 weeks (41 to 46). At the end of the experiment, 20 hens (one hen from each replicate) were slaughtered, and the samples of bone and shell gland (approximately 50 mg) were surgically taken immediately after slaughter for Real-time PCR. The results indicated that dietary GEN increased egg production, feed intake, and egg mass; however, it decreased egg weight (p &lt;0.05). Furthermore, the feed conversion ratio was greater in birds received GEN, compared to those in the control group (p &lt;0.05). GEN enhanced egg quality indices included eggshell strength, thickness, and percentage (p &lt;0.05). Mechanical properties of the tibia, such as weight, length, and breaking strength were also increased by GEN (p &lt;0.05). Moreover, dietary GEN increased the calcium content of the tibia (p &lt;0.05). The mRNA expression of Calbindin-D28k (CaBP-D28k) and transient receptor potential vanilloid channel type 6 (TRPV6) upregulated in eggshell glands of hens treated with GEN paralleled to the controls (p &lt;0.05). In conclusion, the findings of the present study showed that GEN had the potential to improve the bone physical characteristics, mineralization, and the productive performance of Hy-line W-36 laying hens in their post-peak period., (Copyright © 2021, Author(s). Published by Kowsar.)

The aim of the present study was to investigate the efficacy of early probiotics (single dose) administered in different ways, on quails' performance, small intestine morphology, blood biochemistry, and immune response. In total, 192 day-old chicks were used in one of the following experimental groups before being transferred to a raising room: 1) Control (no probiotic administered), 2) oral gavage, 3) spray, and 4) vent lip. Four replicates of 12 chicks per cage were considered for each treatment and birds were raised up to 35 d in the same conditions. Probiotic treated birds had higher d 1 to 35 feed intake than the control group (P < 0.05). In addition, oral-gavaged birds had a higher body weight gain as compared to the control (P < 0.05). The values of duodenum length and villus height of the oral group and ileum length and villus height of the vent lip group were greater than that of the control (P < 0.01). Regardless of the method of administration, probiotics resulted in deeper crypts and in a higher number of goblet cells in the duodenum and ileum as compared to the control (P < 0.01). The administration of probiotics resulted in increased plasma uric acid (P < 0.05), glucose, and total protein (P < 0.01). The concentration of hemoglobin was slightly higher in probiotic-supplemented groups. While a decreased concentration of triglyceride was observed in vent-lip probiotic-administered birds compared to control (P < 0.05), the concentration of cholesterol was not significantly affected by treatments (P > 0.01). None of the immune-related parameters were affected by the probiotic (P > 0.05). Single dose usage of probiotics exerts its beneficial effects on quails' body weight gain, feed intake and mortality in 1 to 35 d period, regardless of the route of administration. This work generally supports the efficacy of single-dose usage of probiotics and suggests the spray of probiotics as an early, single-dose administration method., (© 2017 Poultry Science Association Inc.)