PMID- 35574467
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20230916
IS  - 1664-042X (Print)
IS  - 1664-042X (Electronic)
IS  - 1664-042X (Linking)
VI  - 13
DP  - 2022
TI  - Dietary Energy and Protein Levels During the Prelay Period on Production 
      Performance, Egg Quality, Expression of Genes in Hypothalamus-Pituitary-Ovary 
      Axis, and Bone Parameters in Aged Laying Hens.
PG  - 887381
LID - 10.3389/fphys.2022.887381 [doi]
LID - 887381
AB  - Nutrition during the pre-lay period takes effect on the production performance in 
      the laying flock. This study evaluated the effects of dietary energy and protein 
      levels in pre-lay diet on performance during the whole laying period and the egg 
      quality, bone quality, and mRNA expression of hypothalamus-pituitary-gonadal 
      (HPG) axis-related genes of hens at the end of the laying cycle. A total of 1,856 
      15-wk old Hy-Line brown pullets were randomly assigned to one of the four dietary 
      treatments: using a 2 x 2 factorial arrangement with 2 energy levels (2,700 and 
      2,800 kcal/kg ME, respectively) and 2 protein levels (15 and 16.5% CP, 
      respectively). Pullets were fed ad libitum from 15 to 20 wk and from 20 wk 
      onward, fed with a similar laying diet till 72 wk of age. At 72 wk, the 
      expression of genes in the hypothalamus, pituitary, ovarian, and follicles and 
      bone quality was evaluated. At 72wk, there were no differences in production 
      performance, BW, organ index, and ovarian parameters among the dietary 
      treatments. High-CP diet increased the egg shape index and eggshell thickness (p 
      < 0.05), but the eggshell breaking strength, Haugh unit, and albumen height did 
      not differ among the treatments. Neither dietary energy nor protein level took an 
      effect of bone quality. Low-energy diet increased the mRNA expression of 
      gonadotropin-releasing hormone-1 (GnRH-1) in the hypothalamus (p < 0.05). The 
      mRNA expression level of estrogen receptor-1 (ESR-1) in the hypothalamus and 
      ovary was elevated by the 2,700 ME-15%CP diet (p < 0.05). The expression of 
      cytochrome family 17 subfamily A polypeptide 1 (CYP17A1) in the large white 
      follicle (LWF), small yellow follicles (SYF) and dominant follicle (DF) was 
      decreased by the 2,800 kcal/kg diet (p < 0.05). These results indicate that the 
      prelay diet had no influence on the production performance but had minimal effect 
      on the eggshell characteristics and bone parameters. These results suggest that 
      the energy and protein level of the prelay diet changes the expression of HPG 
      axis-related genes of hens around the end of the laying cycle without changing 
      the circulating sex hormone profile. The effect of prelay diet on the endocrinal 
      adjustment at the end of the laying cycle needs to be investigated further.
CI  - Copyright (c) 2022 Xin, Ma, Jiao, Wang, Li, Zhou, Zhao and Lin.
FAU - Xin, Qian
AU  - Xin Q
AD  - Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control 
      and Prevention, College of Animal Science and Veterinary Medicine, Shandong 
      Agricultural University, Tai'an, China.
FAU - Ma, Ning
AU  - Ma N
AD  - Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control 
      and Prevention, College of Animal Science and Veterinary Medicine, Shandong 
      Agricultural University, Tai'an, China.
FAU - Jiao, Hongchao
AU  - Jiao H
AD  - Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control 
      and Prevention, College of Animal Science and Veterinary Medicine, Shandong 
      Agricultural University, Tai'an, China.
FAU - Wang, Xiaojuan
AU  - Wang X
AD  - Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control 
      and Prevention, College of Animal Science and Veterinary Medicine, Shandong 
      Agricultural University, Tai'an, China.
FAU - Li, Haifang
AU  - Li H
AD  - College of Life Sciences, Shandong Agricultural University, Tai'an, China.
FAU - Zhou, Yunlei
AU  - Zhou Y
AD  - College of Chemistry and Material Science, Shandong Agricultural University, 
      Tai'an, China.
FAU - Zhao, Jingpeng
AU  - Zhao J
AD  - Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control 
      and Prevention, College of Animal Science and Veterinary Medicine, Shandong 
      Agricultural University, Tai'an, China.
FAU - Lin, Hai
AU  - Lin H
AD  - Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control 
      and Prevention, College of Animal Science and Veterinary Medicine, Shandong 
      Agricultural University, Tai'an, China.
LA  - eng
PT  - Journal Article
DEP - 20220428
PL  - Switzerland
TA  - Front Physiol
JT  - Frontiers in physiology
JID - 101549006
PMC - PMC9096247
OTO - NOTNLM
OT  - bone quality
OT  - egg quality
OT  - energy
OT  - gene expression
OT  - protein
COIS- The authors declare that the research was conducted in the absence of any 
      commercial or financial relationships that could be construed as a potential 
      conflict of interest.
EDAT- 2022/05/17 06:00
MHDA- 2022/05/17 06:01
PMCR- 2022/04/28
CRDT- 2022/05/16 04:43
PHST- 2022/03/01 00:00 [received]
PHST- 2022/04/12 00:00 [accepted]
PHST- 2022/05/16 04:43 [entrez]
PHST- 2022/05/17 06:00 [pubmed]
PHST- 2022/05/17 06:01 [medline]
PHST- 2022/04/28 00:00 [pmc-release]
AID - 887381 [pii]
AID - 10.3389/fphys.2022.887381 [doi]
PST - epublish
SO  - Front Physiol. 2022 Apr 28;13:887381. doi: 10.3389/fphys.2022.887381. eCollection 
      2022.