• Title/Summary/Keyword: Inclusion Ratio

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Digestibility, ruminal fermentation, and nitrogen balance with various feeding levels of oil palm fronds treated with Lentinus sajor-caju in goats

  • Hamchara, Puwadon;Chanjula, Pin;Cherdthong, Anusorn;Wanapat, Metha
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.10
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    • pp.1619-1626
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    • 2018
  • Objective: This study was an attempt to investigate the effect of levels of fungal (Lentinus sajor-caju) treated oil palm fronds (FTOPF) on digestibility, rumen fermentation, and nitrogen balance in goats. Methods: Four 16 month old male crossbred (Thai Native${\times}$Anglo Nubian) goats with initial body weights of $33.5{\pm}1.7kg$ were randomly assigned according to a $4{\times}4$ Latin square design. Four levels of FTOPF were assigned for feed intake. The experimental treatments consisted of 0%, 33%, 67%, and 100% of oil palm fronds (OPF) being replaced by FTOPF. Results: The results revealed that total dry matter intake and nutrient intake were not influenced (p>0.05) by the inclusion of FTOPF. However, the efficiency values of the digestibility of the dry matter, organic matter, crude protein, neutral detergent fiber, acid detergent fiber, and acid detergent lignin on FTOPF were higher (p<0.05) in treatments with 33%, 67%, and 100% of FTOPF compared with 0% of FTOPF. FTOPF feeding did not change the rumen pH, temperature, and $NH_3-N$. However, the FTOPF levels did affect the total volatile fatty acid (VFA), molar proportion of acetate, propionate, butyrate, ratio of acetic (propionic acid and acetic) plus butyric (propionic acid), and production of $CH_4$. The totals of VFA and propionate was lower in goat fed with 0% of FTOPF than in those of the other groups (p<0.05). The amount of nitrogen retention based on g/d/animal or the percentage of nitrogen retained was the lowest the goat fed with 0% of FTOPF (p<0.05), whereas nitrogen intake, excretion, and absorption were not changed among treatments. Conclusion: Based on this study, FTOPF could be effectively used as an alternative roughage source in total mixed ration diets, constituting at least up to 100% of OPF.

Effect of probiotics and xylo-oligosaccharide supplementation on nutrient digestibility, intestinal health and noxious gas emission in weanling pigs

  • Liu, JB;Cao, SC;Liu, J;Xie, YN;Zhang, HF
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.10
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    • pp.1660-1669
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    • 2018
  • Objective: This study was conducted to evaluate the effect of probiotics (Bacillus subtilis and Enterococcus faecium) and xylo-oligosaccharide (XOS) supplementation on growth performance, nutrient digestibility, serum profiles, intestinal health, fecal microbiota and noxious gas emission in weanling pigs. Methods: A total of 240 weanling pigs ([Yorkshire${\times}$Landrace]${\times}$Duroc) with an average body weight (BW) of $6.3{\pm}0.15kg$ were used in this 28-day trial. Pigs were randomly allocated in 1 of the following 4 dietary treatments in a $2{\times}2$ factorial arrangement with 2 levels of probiotics (0 and 500 mg/kg probiotics) and XOS (0 and 200 mg/kg XOS) based on the BW and sex. Results: Administration of probiotics or XOS improved average daily gain (p<0.05) during 0 to 14 d and the overall period, while pigs that were treated with XOS had a greater average daily gain and feed efficiency (p<0.05) compared with unsupplemented treatments throughout 15 to 28 d and the whole experiment. Either probiotics or XOS treatments increased the apparent total tract digestibility of nutrients (p<0.05) during 0 to 14 d. No effects on serum profiles were observed among treatments. The XOS increased villus height: crypt depth ratio in jejunum (p<0.05). The supplementation of probiotics (500 mg/kg) or XOS (200 mg/kg) alone improved the apparent total tract digestibility of dry matter, nitrogen and gross energy on d 14, the activity of trypsin and decreased fecal NH3 concentration (p<0.05). Administration of XOS decreased fecal Escherichia coli counts (p<0.05), while increased lactobacilli (p<0.05) on d 14. There was no interaction between dietary supplementation of probiotics and XOS. Conclusion: Inclusion of XOS at 200 mg/kg or probiotics (Bacillus subtilis and Enterococcus faecium) at 500 mg/kg in diets containing no antibiotics significantly improved the growth performance of weanling pigs. Once XOS is supplemented, further providing of probiotics is not needed since it exerts little additional effects.

Effect of Supplementation of Bacillus subtilis LS 1-2 Grown on Citrus-juice Waste and Corn-soybean Meal Substrate on Growth Performance, Nutrient Retention, Caecal Microbiology and Small Intestinal Morphology of Broilers

  • Sen, Sinol;Ingale, S.L.;Kim, J.S.;Kim, K.H.;Kim, Y.W.;Khong, Chou;Lohakare, J.D.;Kim, E.K.;Kim, H.S.;Kwon, I.K.;Chae, B.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.8
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    • pp.1120-1127
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    • 2011
  • A feeding trial was conducted to investigate the effect of dietary supplementation of Bacillus subtilis LS 1-2 grown on citrus-juice waste and corn-soybean substrate on growth performance, nutrient retention, caecal microbial population and intestinal morphology in broilers. Three hundred twenty d-old Ross chicks were randomly allotted to 4 treatments on the basis of BW in a randomized complete block design. Each treatment had 4 replicates of 20 chicks in each. Experimental diets were fed in 2 phases, starter (d 0 to 21) and finisher (d 21 to 35). Dietary treatments were; negative control (NC: basal diet without any antimicrobial), positive control (PC: basal diet added with 20 mg/kg Avilamycin), basal diet added with 0.30% Bacillus subtilis LS 1-2 grown on corn-soybean substrate (P1), and basal diet added with 0.30% Bacillus subtilis LS 1-2 grown on citrus-juice waste substrate (P2). Overall BW gain, feed intake and FCR were better (p<0.05) in PC, P1 and P2 treatments as compared to NC. Moreover, overall BW gain and FCR in PC and P2 treatments were greater than P1. Retention of CP, GE (d 21, d 35) and DM (d 35) were increased (p<0.05) in treatments PC, P1 and P2 compared with NC. At d 35, caecal Clostridium and Coliform counts were lower (p<0.05) in treatments PC, P1 and P2 than NC. Moreover, Clostridium and Coliform counts in treatment PC was lower (p<0.05) than P1. Villus height and villus height to crypt depth ratio in both duodenum and ileum were increased (p<0.05) in treatments PC, P1, P2 as compared to NC. However, retention of nutrients, caecal microbial population and intestinal morphology remained comparable among treatments P1 and P2. It is concluded that Bacillus subtilis LS 1-2 inclusion at 0.30% level had beneficial effects on broilers' growth performance, nutrient retention, caecal microflora and intestinal morphology. Additionally, citrus-juice waste can be used as substrate for growth of probiotic Bacillus subtilis LS 1-2.

Effect on quanti-quality milk and mozzarella cheese characteristics with further increasing the level of dried stoned olive pomace in diet for lactating buffalo

  • Taticchi, A.;Bartocci, S.;Servili, M.;Di Giovanni, S.;Pauselli, M.;Mourvaki, E.;Zilio, D. Meo;Terramoccia, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.11
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    • pp.1605-1611
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    • 2017
  • Objective: Following a previous report, an experiment was conducted to determine the effect of increasing level of dried stoned olives pomaces (DSOP) in the diet of lactating buffaloes on milk and mozzarella cheese yield and characteristics. Methods: Sixteen pluriparous buffaloes distributed into two groups were fed an isoenergetic (0.9 milk forage unit/kg) and isoprotein (149 g/kg dry matter [DM] of crude protein) diet, with or without DSOP. Each animal received 17 kg DM/d. Samples of forages and concentrates were weekly collected and used for duplicate chemical analyses. Individual milk samples from each control were analyzed for chemical and coagulating parameters and daily production of mozzarella cheese was estimated. At the end of the trial, bulk milk of each group was processed to produce mozzarella cheese and chemical (fat, protein, ash, pH) composition, fatty acids composition, carotenoids and tocopherols content were determined. A sensory test was also performed. The oxidative stability was measured on mozzarella cheese and on governing liquid. Results: No significant differences were observed, neither for milk yield and body condition score, nor for milk characteristics. The fat was higher (p<0.05) in mozzarella of DSOP fed group but, saturated fatty acids were lower and unsaturated higher (p<0.01). Furthermore, lower atherogenic (p<0.01), and thrombogenic (p<0.05) indices were found in mozzarella cheese of DSOP fed group. In addition, the administration of DSOP did not affect the mozzarella cheese oxidative stability and no negative effect was found in the sensory properties. Conclusion: No contraindications appeared for the inclusion of DSOP in the diet of lactating buffaloes. Besides, important effects on mozzarella cheese quality were obtained, such as a modification of fat content and attributes with an increment in the mono-unsaturated. Additionally, a lower saturated/unsaturated ratio and atherogenic and thrombogenic indices suggest an improvement of dietetic and nutritional characteristics of mozzarella cheese.

Influence of dietary supplementation of autolyzed whole yeast and yeast cell wall products on broiler chickens

  • Ahiwe, Emmanuel Uchenna;Abdallh, Medani Eldow;Chang'a, Edwin Peter;Omede, Apeh Akwu;Al-Qahtani, Mohammed;Gausi, Harriet;Graham, Hadden;Iji, Paul Ade
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.4
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    • pp.579-587
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    • 2020
  • Objective: This study evaluated the effect of yeast products on growth performance, visceral organ weights, endogenous enzyme activities, ileal nutrient digestibility and meat yield of broiler chickens fed diets containing autolyzed whole yeast (WY) and yeast cell walls (YCW) at varying levels of inclusion. Methods: Nine dietary treatments consisting of WY or YCW included at 0.5, 1.0, 1.5, or 2.0 g/kg diet and a control diet without yeast supplementation was used in the experiment. Each of the nine treatments was replicated six times with nine birds per replicate. Birds were housed in cages, in climate-controlled rooms and fed starter, grower and finisher diets. Results: There was an improvement (p<0.05) in body weight gain and feed conversion ratio on d 10, 24, and 35 for birds fed 1.0 to 2.0 g/kg WY or YCW diet. Small intestine weight was heavier on d 10 and 24 for birds on higher levels of WY and YCW compared to the control group. On d 10 and 24, there was a significant increase (p<0.05) in tissue protein content and pancreatic enzyme activities (trypsin and chymotrypsin) of birds on 1.5 to 2.0 g/kg WY and YCW diets compared to the control group. Compared to the control group, birds on WY (2.0 g/kg diet) and YCW (at 1.5 and 2.0 g/kg diet) had better (p<0.05) protein digestibility on d 24. On d 35, there was significant improvement (p<0.05) in percentage of carcass, absolute and relative breast weight for broiler chickens fed WY and YCW mostly at 2 g/kg diet compared to birds on the control diet. Conclusion: Supplementation of diets with autolyzed WY and YCW products especially at 1.5 to 2.0 g/kg diet improved broiler chicken performance and meat yield through their positive effects on ileal protein digestibility and pancreatic enzyme activities.

Quantification of Karanjin, Tannin and Trypsin Inhibitors in Raw and Detoxified Expeller and Solvent Extracted Karanj (Pongamia glabra) Cake

  • Panda, A.K.;Sastry, V.R.B.;Kumar, A.;Saha, S.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.12
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    • pp.1776-1783
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    • 2006
  • Despite being a rich source of protein (28-34%), karanj (Pongamia glabra) cake is found to be bitter in taste and toxic in nature owing to the presence of flavonoid (karanjin), tannin and trypsin inhibitor, thereby restricting its safe inclusion in poultry rations. Feeding of karanj cake at higher levels (>10%) adversely affected the growth performance of poultry due to the presence of these toxic factors. Therefore, efforts were made to detoxify karanj cake by various physico-chemical methods such as dry heat, water washing, pressure cooking, alkali and acid treatments and microbiological treatment with Sacchraromyces cerevisiae (strain S-49). The level of residual karanjin in raw and variously processed cake was quantified by high performance liquid chromatography and tannin and trypsin inhibitor was quantified by titrametric and colorimetric methods, respectively. The karanjin, tannin and trypsin inhibitor levels in such solvent and expeller pressed karanj cake were 0.132, 3.766 and 6.550 and 0.324, 3.172 and 8.513%, respectively. Pressure-cooking of solvent extracted karanj cake (SKC) substantially reduced the karanjin content at a cake:water ratio of 1:0.5 with 30-minute cooking. Among chemical methods, 1.5% (w/w) NaOH was very effective in reducing the karanjin content. $Ca(OH)_2$ treatment was also equally effective in karanjin reduction, but at a higher concentration of 3.0% (w/w). A similar trend was noticed with respect to treatment of expeller pressed karanj cake (EKC). Pressure cooking of EKC was effective in reducing the karanjin level of the cake. Among chemical methods alkali treatment [2% (w/w) NaOH] substantially reduced the karanjin levels of the cake. Other methods such as water washing, dry heat, HCl, glacial acetic acid, urea-ammoniation, combined acid and alkali, and microbiological treatments marginally reduced the karanjin concentration of SKC and EKC. Treatment of both SKC and EKC with 1.5% and 2.0% NaOH (w/w) was the most effective method in reducing the tannin content. Among the various methods of detoxification, dry heat, pressure cooking and microbiological treatment with Saccharomyces cerevisiae were substantially effective in reducing the trypsin inhibitor activity in both SKC and EKC. Based on reduction in karanjin, in addition to tannin and trypsin inhibitor activity, detoxification of SKC with either 1.5% NaOH or 3% $Ca(OH)_2$, w/w) and with 2% NaOH were more effective. Despite the effectiveness of pressure cooking in reducing the karanjin content, it could not be recommended for detoxification because of the practical difficulties in adopting the technology as well as for economic considerations.

Lactation Performance of German Fawn Goat in Relation to Feeding Level and Dietary Protein Protection

  • Chowdhury, S.A.;Rexroth, H.;Kijora, C.;Peters, K.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.2
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    • pp.222-237
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    • 2002
  • Effects of high and low levels of feeding with or without protected protein on the performance of lactating goats were studied. Twenty four German Fawn goats either from 1st ($43.37{\pm}3.937$ kg and 2 year old) or 3rd $62.64{\pm}6.783$ kg and 4-5 year old) parity were used for the trial. Feeding levels were 7.2 (I) and 5.2 (II) MJ ME/litre of milk of 3.5% fat in addition to that of the maintenance allowance. At each feeding level, diet had either unprotected (U) or formaldehyde protected (P) soya-meal. Thus, four diets were IU, IP, IIU and IIP, having six animals in each. The diets were composed of hay and pellet (10:4:1 of beet pulp : barley : soya-meal). Effect of feeding level, protein protection, parity, health status and kid number on intake, milk yield, milk composition, growth rate of goats were recorded across the 21 weeks of study. High feeding level resulted increase (p<0.001) in estimated metabolizable energy (ME) and metabolizable protein (MP) availability. Dietary inclusion of protected soya-meal increased (p<0.001) the estimated MP but not the ME availability. Animals in 1st parity ate more (p<0.001) DM (111 vs. 102 g/kg $W^{0.75}$/d) than those in 3rd parity. Animals with twin kids (110 g/kg $W^{0.75}$/d) had higher (p<0.001) DM intake than those with single kid (102 g/kg $W^{0.75}$/d). Fat (4%) corrected milk (FCM) yield was not effected by high (1,924 g/d) or low (1,927 g/d) feeding level but increased (p<0.001) with protected (2,166 g/d) compared with unprotected (1,703 g/d) soya-meal. FCM yield for four dietary combinations were 1,806, 2,078, 1,600 and 2,254 g/d for diets IU, IP, IIU and IIP, respectively. For unit increase (g) in estimated MP availability relative to ME (MJ) intake, FCM yield increased ($1,418{\pm}275.6$) g daily ($r^2$=0.58; p<0.001). Milk fat (3.14 vs. 3.54%; p<0.001) and protein (2.94 vs. 3.04% p<0.05) contents were lower at high than the low feeding level. Protected protein increased (p<0.001) the fat, lactose and net energy (NE) content of milk. Milk urea concentration of 175, 183, 192 and 204 mg/l for diets IU, IP, IIU and IIP, respectively indicated lower RDP content of these diets. The RDP contents were 6.97, 6.70, 7.30 and 6.83 g/MJ of ME for diets IU, IP, IIU and IIP, respectively. Live weight change over the experimental period were 41, 6, 17 and 19 g/d. Absence of any positive response of high feeding was probably due to inefficient rumen fermentation resulting from inadequate RDP supply. Protected protein improved production performance apparently by increasing MP:ME ratio in the absorbed nutrient.

Effects of Phytase and Enzyme Complex Supplementation to Diets with Different Nutrient Levels on Growth Performance and Ileal Nutrient Digestibility of Weaned Pigs

  • Shim, Y.H.;Chae, B.J.;Lee, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.4
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    • pp.523-532
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    • 2004
  • An experiment was conducted to investigate the effect of microbial phytase ($Natuphos^{R}$) supplementation in combination with enzyme complex (composed of enzymes targeted to SBM dietary components such as $\alpha$-galactosides and galactomannans; $Endo-Power^{R}$) to diet with low nutrient levels on growth performance and ileal nutrient digestibility of weaned pigs. A total of 210 crossbred weaned pigs (Landrace$\times$Yorkshire$\times$Duroc), 6.68$\pm$0.98 kg of initial body weight, were randomly allotted to five dietary treatments, based on weight and age, according to a randomized complete block design. There were three pens per treatment and 14 pigs per pen. The dietary treatments were 1) CON (Control diet with no phytase and enzyme complex (EC)), 2) LP+EC 100 (Control diet with 0.15% unit lower available phosphorus (aP) level+0.1% phytase (500 FTU/kg diet) and 0.1% enzyme complex), 3) LP+EC 80 (Control diet with 0.15% unit lower aP level+0.08% phytase (400 FTU/kg diet) and 0.08% enzyme complex, 4) LPEA+EC 100 (Control diet with 0.15% unit lower aP and 3% lower ME and amino acid levels (lysine, methionine, threonine and typtophan)+0.1% phytase (500 FTU/kg diet) and 0.1% enzyme complex), 5) LPEA+EC 80 (Control diet with 0.15% unit lower aP and 3% lower ME and amino acid levels+0.08% phytase (400 FTU/ kg diet) and 0.08% enzyme complex). For the determination of ileal nutrients digestibility, a total of 15 T-cannulated pigs (initial body weight; 7.52$\pm$1.24 kg; 3 replicates per treatment) were used in the present study. Piglets were weighted and allotted into same dietary treatments as one in growth trial and phase I experimental diets were provided for ileal digestibility study. There was no significant difference (p>0.05) in average daily gain (ADG) and average daily feed intake (ADFI) among dietary treatments during the whole experimental period (0 to 5 weeks). However, piglets in LP+EC 100 group had a significantly higher gain/feed ratio (G:F) than piglets had in control (p<0.05). Crude protein, energy and phosphorus digestibilities were significantly improved when both of phytase and enzyme complex were supplemented at the revel of 0.1%, respectively to diets with low nutrient level (aP or (and) ME and amino acids) (p<0.05). Piglets in LP+EC 100 and LPEA+EC 100 groups showed significantly higher phosphorus content (%) in bone than that of piglets in control group (p<0.05). Supplementation of both of phytase and enzyme complex at 0.1%, respectively, to diet with low nutrient levels (aP or (and) ME and amino acids) significantly improved total ileal essential amino acid and nonessential amino acid digestibilities compared to control group (p<0.05). In conclusion, the results from the present study suggest that the simultaneous inclusion of phytase and enzyme complex to diets at recommended level is advantageous with respect to improving growth performance and nutrient digestibility of weaned pigs and may contribute to increased economic return when added to corn-soy based weaned pig diets.

Interactions between Water-Soluble Polyparacyclophanes and Drugs (III) -Complex Formation of Water-Soluble Polyparacyclophanes with Fluorescent Hydrophobic Naphthalene Derivatives in Aqueous Solution- (수용성 폴리파라시클로판류와 약물과의 상호작용(제 3보)-수용액 중 수용성 폴리파라시클로판류와 형광 소수 나프탈렌 유도체류와의 복합체 형성-)

  • Chun, In-Koo;Lee, Min-Hwa
    • Journal of Pharmaceutical Investigation
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    • v.19 no.2
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    • pp.71-79
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    • 1989
  • Complex formation of water-soluble polyparacyclophanes bearing two diphenylmethane or two diphenyl ether skeletons with l-anilinonaphthalene-8-sulfonate (ANS) and 2-p-toluidinylnaphthalene-6-sulfonate (TNS) was investigated quantitatively to develop useful host compounds comparing with ${\alpha}\;-\;and\;{\beta}-cyc1odextrins$$({\alpha}-\;and\;{\beta}-CyDs$) in aqueous solution. Benesi-Hildebrand type analysis of the fluorescent intensity showed that the dissociation constants (Kd) of paracyclophane-ANS complexes were $1.55\;{\times}\;10^{-4}M$ for 1,6,20,25-tetraaza[6.1.6.1]paracyclophane(CPM 44) and $1.23\;{\times}\;10^{-4}M$ for 1,7,21,27-tetraaza[7.1.7.1]paracyclophane (CPM 55), and those of paracyclophane-TNS complexes were $6.99\;{\times}\;10^{-6}M$ for CPM 44 and $6.23\;{\times}\;10^{-5}M$ for CPM 55, in 1:1 molar ratio. On the other hand, the Kd values of 1,7,21,27-tetraaza-14,34-dioxa[7.1.7.1]paracyclophane (CPE 55)-ANS, 1,8,22,29-tetraaza-15,36-dioxa[8.1.8.1]paracyclophane (CPE 66)-ANS, CPE 55-TNS, CPE 66-TNS complexes were $1.75\;{\times}\;10^{-3}M$, $3.07\;{\times}\;10^{-3}M$, $3.75\;{\times}\;10^{-3}M$ and $2.15\;{\times}\;10^{-3}M$, respectively. On the contrary, the Kd values of ${\alpha}-CyD-ANS$, ${\beta}-CyD-ANS$, ${\alpha}-CyD-TNS$ and ${\beta}-CyD-TNS$ complexes were found to be $3.98\;{\times}\;10^{-2}M$, $1.05\;{\times}\;10^{-2}M$, $1.38\;{\times}\;10^{-2}M$ and $3.52\;{\times}\;10^{-4}M$, respectively. These results mean that the complexation of CPMs with ANS or TNS is by 5.6-1,975 fold stronger than that for ${\alpha}-or\;{\beta}-CyDs$, and the complex formation of CPEs with ANS or TNS is nearly same as or somewhat stronger than that for ${\alpha}-or\;{\beta}-CyDs$. From the Kd values determined at different temperatures, thermodynamic parameters were calculated and the complexation was found to be a spontaneous exothermic reaction. The effects of pH on Kd values of CPM 44-ANS, and CPM 55-ANS complexes were negligible in the range of pH 1.2-1.8. However, the Kd values of these complexes increased significantly with increasing ionic strength.

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Effect of luteal phase support with vaginal progesterone on pregnancy outcomes in natural frozen embryo transfer cycles: A meta-analysis

  • Seol, Aeran;Shim, Yoo Jin;Kim, Sung Woo;Kim, Seul Ki;Lee, Jung Ryeol;Jee, Byung Chul;Suh, Chang Suk;Kim, Seok Hyun
    • Clinical and Experimental Reproductive Medicine
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    • v.47 no.2
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    • pp.147-152
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    • 2020
  • Objective: The purpose of this study was to determine the effect of vaginal progesterone for luteal phase support (LPS) on the clinical pregnancy rate (CPR) in natural frozen embryo transfer (FET) cycles via a meta-analysis. Methods: We performed a meta-analysis of randomized controlled trials (RCTs) and retrospective studies that met our selection criteria. Four online databases (PubMed, Embase, Medline, and the Cochrane Library) were searched between January 2017 and May 2017. Studies were selected according to predefined inclusion criteria and meta-analyzed using R software version 2.14.2. The main outcome measure was CPR. Results: A total of 18 studies were reviewed and assessed for eligibility. One RCT (n = 435) and three retrospective studies (n = 3,033) met the selection criteria. In a meta-analysis of the selected studies, we found no significant difference in the CPR (odds ratio [OR], 0.96; 95% confidence interval [CI], 0.60-1.55) between the vaginal progesterone and control groups. An analysis of the two retrospective cohort studies that reported the live birth rate (LBR) following FET showed a significantly higher LBR in the vaginal progesterone group (OR, 1.72; 95% CI, 1.21-2.46). A subgroup meta-analysis of FET conducted 5 days after injection of human chorionic gonadotropin showed no significant differences between the two groups with regard to the CPR (OR, 1.18; 95% CI, 0.90-1.55) or miscarriage rate (OR, 0.73; 95% CI, 0.36-1.47). Conclusion: The results of this meta-analysis of the currently available literature suggest that LPS with vaginal progesterone in natural FET cycles does not improve the CPR.