Effects of sexual pairing pattern on behaviour and reproductive performance in domestic pigeons

Abstract

Same sexual pairing is a widespread but complex phenomenon across a variety of animal groups. However, previous research on its behaviours and potential mechanisms has been limited by small sample sizes and inconsistent experimental conditions. The purpose of this study was to explore the effects of different sexual pairing patterns on the reproductive performance, behaviour dynamics, and plasma reproductive hormone profile of pigeons. During the 270-day experimental observation period, the performance of female-male (FM) pairing and female-female (FF) pairing was systematically compared. The results showed that compared with FM pairing, the average monthly egg production per female of FF pairing was significantly lower (2.98 ± 0.07 vs. 3.84 ± 0.08 eggs/female/month; P < 0.05). However, no significant differences were observed in the single egg rate and egg weight. Behavioural analysis showed that the frequency of nesting behaviour in FF pairing was significantly higher, but the frequency of walking, allopreening, and courtship feeding was lower than that in FF pairing (P < 0.05). The results of hormone determination showed that in the post-oviposition period, the concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E₂) in plasma gradually increased, while the levels of prolactin (PRL) decreased. Compared with FM pairing, FF pairing showed significantly higher PRL concentration in the late period of egg-laying interval (P < 0.05). These findings suggest that pairing patterns regulate hypothalamic-pituitary-gonadal (HPG) axis activity and affect reproductive outcomes by modulating responses to social stimuli. The study provides insights into the endocrine and behavioural mechanisms underlying different sexual pairing patterns in pigeons and supports the potential application of FF pairing as an alternative production strategy in pigeon production.

Introduction

The domestic pigeon is​ one of the earliest domesticated bird species. Pigeon eggs are favored by consumers because of their translucent appearance (Yang et al., 2023), hypoallergenic (Moghtaderi et al., 2020), and unique nutritional profile (Zhang et al., 2025a). Unlike other common poultry, domestic pigeons have unique physiological characteristics, including strict monogamy in the natural environment and a long egg-laying interval (Zhang et al., 2025c). The egg-laying behaviour of female pigeons usually depends on stimulation from their mate. In the pigeon industry that focuses on egg production, eggs are routinely removed shortly after laying, preventing females from entering their natural incubation state. Under these farming conditions, the egg-laying interval (the time between consecutive clutches) becomes the primary limiting factor for total egg yield, making it a crucial trait for agricultural profitability. Furthermore, because male pigeons cannot lay eggs themselves but consume significant amounts of feed, the traditional female-male production mode is economically less efficient compared to other poultry systems where hens lay independently. Studies have shown that same-sex partner preference is very common in animal species. It has been found in arachnids (Scharf and Martin, 2013), birds (MacFarlane et al., 2010) and many mammals (Monk et al., 2019; Gómez et al., 2023). Interestingly, this phenomenon has also been observed among pigeons. When a male pigeon is absent, female pigeons can also pair up and stimulate each other to lay eggs (Jankowiak et al., 2018). Female-female​ pairing has potential economic benefits because it reduces the maintenance cost of male pigeons. However, the physiological differences in reproduction between female-female pairing and traditional female-male pairing have not been fully clarified. Additionally, the domestic pigeon provides a valuable and tractable model for the study of same-sex pairing. Compared to non-avian species, which rarely yield measurable reproductive outcomes from same-sex pairings, and wild avian species, where unifying environmental conditions for standardized measurement is practically difficult, paired female pigeons can reliably establish lasting bonds and exhibit quantifiable egg-laying behaviour under controlled conditions. Large-scale farming of pigeons also provides significant advantages for experimental research. These characteristics make it possible to systematically study how pairing patterns affect reproduction—an approach that is difficult to implement in other animal research systems.

The reproductive performance of domestic birds, especially egg production, is fundamentally regulated by the hypothalamic-pituitary-gonadal (HPG) axis through the coordinated secretion of reproductive hormones (Bain et al., 2016; Wang et al., 2024). Key hormones include GnRH from the hypothalamus, which stimulates the pituitary gland to secrete FSH and LH (Sharp et al., 1998). These gonadotropins are essential for ovarian follicle development, steroidogenesis, and ultimately, ovulation (Bédécarrats, 2015). Following ovulation, PRL plays a key role, as it is necessary to induce and maintain brooding behaviour, and elevated PRL levels can inhibit the secretion of GnRH, thus preventing further ovulation and leading to the cessation of egg-laying (Sharp and Blache, 2003). The complex interactions among GnRH, FSH, and LH promote follicular development and ovulation, but PRL may inhibit these processes, which are crucial for egg-laying cycle.

The secretion of these hormones of domestic birds, along with associated behaviours, and reproductive performance is significantly influenced by many factors, including photoperiod (Yan et al., 2024; Chen et al., 2025; Li et al., 2026), nutritional status (Zheng et al., 2025a; b), and breeding (Shi et al., 2023; Ma et al., 2023; Zhang et al., 2025b). However, the effects of different pairing methods on pigeon reproductive performance, behaviours, and hormone secretion remain unclear. In this study, we examined the egg-laying performance, behavioural frequency, and plasma reproductive hormone concentrations in both female-male and female-female paired pigeons after oviposition. The results demonstrate the comprehensive effects of pairing mode on reproductive hormones, egg-laying performance, and behavioural frequency, and reveal the interconnections among these factors.

Materials and methods

Animals, diets, and housing

A total of 650 five-month-old Taishen pigeons (150 males, 500 females) were fed in Nanjing Dongchen Pigeon Industry Co., Ltd. The pigeons were systematically divided into two experimental groups: one group consisted of female–male pairs (one female and one male), and the other consisted of female–female pairs (two females). All pairs underwent a one-month environmental adaptation and behavioural observation period under controlled conditions. During this period, pairs displaying affiliative behaviours (e.g., allopreening, courtship feeding, or persistent co-occupation of the nest) were identified and retained for subsequent study. After behavioural screening, a total of 289 stable pairs were selected for the formal experiment, including 139 female–male (FM) pairs and 150 female–female (FF) pairs. Pairs laying fewer than three clutches during the 270-day observation period were excluded. Ultimately, a final dataset of 243 pairs (113 FM and 130 FF) remained. All subsequent analyses, including reproductive performance, behavioural frequencies, and their correlations, were based on these remaining pairs.

All pigeons were housed in individual pens and maintained under a controlled photoperiod, with supplemental lighting provided daily from 05:00 to 07:00 and from 19:00 to 22:00. During the experiment, water was available ad libitum, and feed was delivered via an automatic feeding system.

Reproductive performance

Eggs were removed within 12 hours of laying to prevent the onset of the incubation phase, and the laying date was carefully recorded for each egg. Data collection commenced with the onset of laying by the first pair and continued for 270 days. Since pigeons usually lay two eggs in a clutch, the egg-laying interval was determined using this formula:

To standardize the evaluation of reproductive output across groups with different numbers of females per cage (FM: 1 female; FF: 2 females), reproductive performance was quantified as the monthly egg production per female. For each independent pair/cage, the total number of eggs collected within each 30-day interval was recorded. This value was then divided by the number of female individuals in the respective cage (1 for FM and 2 for FF) to yield the normalized monthly egg yield per capita. This normalization ensures that the comparison reflects the reproductive efficiency of individual females rather than the total output per cage.

The single-egg rate was calculated to quantify the occurrence of clutches containing only one egg, which deviates from the typical two-egg clutch pattern in pigeons. This metric was determined using the following formula:

$$\text{Single-egg}\text{rate}(\%)=(\text{Number}\text{of}\text{single}-\text{egg}\text{clutches}/\text{Total}\text{number}\text{of}\text{clutches})\times 100\%.$$

Determination of the concentrations of reproductive hormones

Blood samples were collected through the inferior pterygoid vein on the first day (LI1), the third day (LI3), the fifth day (LI5) and the seventh day (LI7) after laying, with 8 replicates in each group.

To eliminate the potential confounding effects of daily diurnal variations, blood samples were strictly collected between 09:00 and 10:00 on each sampling day. In both FM and FF groups, each time point (LI1, LI3, LI5, and LI7) was represented by a separate set of pigeon pairs to avoid repeated sampling of the same individuals. For the FF group, we specifically selected pairs where both females exhibited synchronized reproductive cycles during the sampling period. To minimize handling stress, the entire blood collection process was consistently completed within approximately 30 seconds per animal. Approximately 1 mL of whole blood was collected from the wing vein of each pigeon directly into EDTA-2K anticoagulant tubes. The samples were then centrifuged at 3000 × g for 10 min. Following centrifugation, approximately 400–500 μL of plasma was successfully isolated and collected, while the red blood cells were discarded. The acquired plasma, which provided more than sufficient volume for the subsequent ELISA assays, was immediately stored at -20°C until further analysis.

The concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E₂), and prolactin (PRL) were determined by enzyme-linked immunosorbent assay (ELISA) using a microplate reader (Infinite M200 Pro Nano Quant; Tecan Trading Co., Ltd., Hombrechtikon, Switzerland) and strictly following the instructions of the kit. All samples from each experimental group per hormone were assayed in duplicate on a single microplate. The intra-assay and inter-assay coefficients of variation (CVs) were < 5% for all assays. The kits demonstrated high specificity with no significant cross-reactivity observed. Analytical sensitivities were 0.1mIU/mL for FSH, 0.1mIU/mL for LH, 1.0pg/mL for E2, and 1.0ng/mL for PRL. The FSH, LH, E2, and PRL ELISA kits were purchased from Shanghai Enzyme-linked Biotechnology Co., Ltd (Shanghai, China).

Observation of the behaviour

We used a surveillance system integrated with automatic feeding machines, with cameras installed to record pigeon activities continuously. To obtain behavioural data, video recordings were retrospectively reviewed and analyzed at four time points daily (08:00, 11:00, 14:00, and 17:00) over a consecutive 30-day period, which commenced during the third month of the experimental recording. We defined and recorded six distinct behavioural categories during each observation session: (A) nesting (maintaining a crouched posture inside the nest), (B) walking (locomotion without apparent purpose), (C) preening (self-maintenance of feathers),​ (D) resting (maintaining a crouched posture outside the nest), (E) allopreening (mutual grooming between pigeons), and (F) courtship feeding (regurgitation of food by male to female during courtship). Six behavioural categories studied are illustrated in Fig. 1.

Fig. 1.

Representative images of the six defined pigeon behaviours.

(A) nesting, (B) walking, (C) preening, (D) resting, (E) allopreening, and (F) courtship feeding.

Statistical analysis

Statistical analyses were performed using R (version 4.4.1) and GraphPad Prism 9.0 (GraphPad Software, San Diego, CA). For reproductive performance, monthly egg production per female was analyzed using a Linear Mixed Model (LMM) via the lmerTest package. The model included Group (FM vs. FF), Month, and their interaction as fixed effects, with Pair ID as a random intercept effect to account for repeated measures. Group differences in the single-egg rate were analyzed using the Mann-Whitney U test, whereas egg weight was compared using an unpaired Welch's t-test.

For behavioural data, group differences were evaluated using a Generalized Linear Mixed Model (GLMM) with a binomial error distribution and a logit link function. Group was set as a fixed effect, while Pair ID and observation Date were included as crossed random effects to control for individual variance and daily environmental fluctuations.

Temporal changes in plasma hormone concentrations within the same group were analyzed using the non-parametric Kruskal-Wallis test, followed by Dunn's multiple comparisons test with Bonferroni correction. Comparisons of hormone concentrations between FM and FF groups at specific time points were performed using the unpaired Mann-Whitney U test. The relationships between behavioural frequencies and total egg production were assessed using Spearman’s rank correlation analysis to account for non-normal distributions.

All tests were two-tailed, and statistical significance was defined as P < 0.05.

Results

The reproductive performance of pigeons

The reproductive performance and egg weight of pigeons under the two different pairing modes are summarized in Fig. 2. To account for potential random factors such as repeated measures from the same pairs, we analyzed overall egg production (eggs/month) using a linear mixed model (LMM). This model revealed a significant main effect of pairing mode, showing that egg production in the FF pairing was significantly lower than that in the FM pairing (2.98 ± 0.07 vs. 3.84 ± 0.08 eggs /female/month; P < 0.05; Fig. 2A). In contrast, we found no significant differences between the two groups regarding either the single-egg rate (11.17% ± 0.91% vs. 13.03% ± 0.96%; P > 0.05; Fig. 2B) or the egg weight (22.90 ± 1.84 vs. 23.12 ± 2.04 g; P > 0.05; Fig. 2C).

Fig. 2.

Reproductive performance of pigeons under FM and FF pairings.

(A) Monthly egg production per female (eggs/female/month). Data were normalized by dividing the total monthly egg count of each cage by the number of female pigeons present (FM = 1; FF = 2). Statistical significance was assessed using a linear mixed model (LMM), incorporating group, month, and their interaction as fixed effects, with Pair ID as a random intercept. (B) Single-egg rate (%). Values represent the average occurrence of single-egg clutches per pair over the observation period. Group differences were analyzed using the unpaired Mann-Whitney U test. (C) Egg weight (g). Data reflect the average weight of eggs collected from each group (n = 75), with comparisons performed using an unpaired Welch’s t-test. Black horizontal lines represent the mean. Sample sizes: FM, n = 113 pairs; FF, n = 130 pairs. Statistical significance is indicated as: **** P < 0.0001; ns, not significant (P > 0.05). Abbreviations: FM, female-male pairing; FF, female-female pairing.

Comparative Analysis of behaviours between the FM and FF pairings

We found significant differences in behavioural activity patterns between the two pairing groups across all observed categories (Fig. 3). Notably, nesting and walking constituted the primary activities, cumulatively accounting for over 50% of all observed behaviours in both groups. FF pairing exhibited a significantly higher proportion of observed behaviours for nesting and resting compared to FM pairing (both P < 0.0001). In contrast, FM pairing demonstrated a significantly higher proportion of observed behaviours for walking (P < 0.0001), preening (P < 0.001), allopreening (P < 0.0001), and courtship feeding (P < 0.0001). Particularly striking was the difference in courtship feeding, where FM pairs showed a nearly five-fold higher proportion compared to FF pairs (5.5% vs. 1.2%). Interestingly, while allopreening is also a direct interactive behaviour, the disparity between the groups was far less pronounced, exhibiting only a 1.3-fold difference (6.9% vs. 5.1%).

Fig. 3.

Comparison of behavioural frequencies between FM and FF pairings. Violin plots illustrate the distribution and density of relative frequencies (proportion of total observed behaviours, based on 120 observations per individual) for six distinct behaviours in pigeons under female-male (FM) and female-female (FF) pairing. Within the violins, solid black horizontal lines represent the mean, and dashed lines indicate the quartiles. Statistical significance was assessed using a generalized linear mixed model (GLMM) with a binomial error distribution, incorporating pair ID and observation date as random effects to account for repeated measures. Sample sizes: FM, n = 113 pairs; FF, n = 130 pairs. Statistical significance is indicated as follows: **** P < 0.0001, *** P < 0.001.

Correlations between egg production and behaviours across pairing groups

To explore the relationship of behaviours to laying performance, we analyzed the association between egg production and the frequencies of six key behaviours in FF and FM pairings (Table 1). In FF pairing, egg production demonstrated significant positive correlations with the frequencies of socio-positive behaviours, specifically allopreening (P < 0.0001) and courtship feeding (P < 0.001). In contrast, walking and preening exhibited negative correlations with egg production (P < 0.001 and P < 0.01). Nesting and resting behaviours showed no significant correlation with egg production in the FF group (P > 0.05).

Table 1.

Correlations of behavioural frequencies with total egg production for FM and FF pigeon pairings.

Behaviour	FM		FF
	r	P.value	r	P.value
Nesting	0.093	0.33	0.13	0.13
Walking	0.080	0.40	-0.31	3.2 × 10⁻⁴
Preening	-0.094	0.33	-0.28	1.5 × 10⁻³
Resting	-0.20	0.037	-0.095	0.28
Allopreening	0.034	0.72	0.45	7.3 × 10⁻⁸
Courtship feeding	0.036	0.71	0.30	5.5 × 10⁻⁴

Note: Correlation analysis was performed using Spearman method (FM, n = 113 pairs; FF, n = 130 pairs). Behavioural data were collected during a 30-day observation period, while egg production data encompassed a 50-day period (including 10-day pre-observation and 10-day post-observation phases) to ensure complete coverage of reproductive cycles.

Within FM pairing, the correlational patterns were markedly different. Egg production was negatively correlated only with resting behaviour (P < 0.05). No other behaviours showed statistically significant associations with reproductive output in this group (P > 0.05 for nesting, walking, preening, allopreening, and courtship feeding).

Plasma reproductive hormone profiles across four physiological periods

We detected the plasma concentrations of FSH, LH, E₂ and PRL in female pigeons during the egg-laying interval (Fig. 4). Within both the FM and FF groups, plasma concentrations of FSH, LH, and E₂ exhibited a significant increasing trend across the four time points from LI1 to LI7 (P < 0.05, Fig. 4A-C), which is consistent with follicular recruitment and maturation processes necessary for subsequent ovulation. In contrast, PRL concentrations within each group decreased significantly over the same temporal period (P < 0.05; Fig. 4D).

Fig. 4.

Reproductive hormone profiles in female pigeons during the egg-laying interval (LI) under FM and FF pairings. (A) Plasma concentration of FSH in female pigeons in LI. (B) Plasma concentration of LH in female pigeons in LI. (C) Plasma concentration of E₂ in female pigeons in LI. (D) Plasma concentration of PRL in female pigeons in LI. Statistical significance between groups at each time point is indicated as follows: ***P < 0.001, **P < 0.01, *P < 0.05; "ns" denotes not significant (P > 0.05). For within-group comparisons across different time points, different uppercase letters (for the FM group) and lowercase letters (for the FF group) indicate significant differences (P < 0.05), whereas bars sharing the same letter indicate no significant difference. Abbreviations:​​ FF, female-female pairing; FM, female-male pairing; LI, laying interval; FSH, follicle-stimulating hormone; LH, luteinizing hormone; E₂, estradiol; PRL, prolactin.

At LI3, the concentrations of FSH (FF: 17.08 ± 0.22 vs. FM: 14.18 ± 0.70 mIU/mL), LH (FF: 87.51 ± 1.41 vs. FM: 74.60 ± 1.14 mIU/mL), and E₂ (FF: 667.37 ± 11.35 vs. FM: 547.69 ± 34.30 pg/mL) in FF pairing were significantly higher than those in FM pairing (all P < 0.05, Fig. 4A-C). Conversely, at this same time point (LI3), PRL concentrations were significantly lower in FF pairing compared to FM pairing (FF: 61.19 ± 1.48 vs. FM: 72.79 ± 0.90 ng/mL; P < 0.05).

By the late period of the interval (LI7), PRL concentrations in FF pairing became significantly higher than those in FM pairing (FF: 54.31 ± 0.97 vs. FM: 38.78 ± 3.00 ng/mL; P < 0.001, Fig. 4D). During these later stages (LI5 and LI7), the concentrations of FSH, LH exhibited a non-significant trend toward higher values in FM pairing (for example, at LI7, FSH: FM 19.45 ± 1.89 vs. FF 18.97 ± 0.49 mIU/mL; LH: FM 101.45 ± 7.07 vs. FF 94.09 ± 0.85 mIU/mL; P > 0.05).

Discussion

This study systematically analyzed the effects of different sex paring patterns on reproductive performance, behaviour, and plasma reproductive hormone profiles of pigeons. The results showed that social structure significantly affected the function of the reproductive axis on multiple levels. Compared with the traditional FM pairing, FF pairing showed unique endocrine and behavioural characteristics. In natural contexts, homosexual pairing remains relatively rare in obligate monogamous birds (Adkins-Regan, 2020). However, our findings are consistent with previous observations that male removal promotes same-sex pairing in pigeons (Jankowiak et al., 2018). The phenomenon that two female pigeons can stimulate each other to lay eggs in the absence of male pigeons is widespread, which indicates that FF pairing is a feasible breeding mode in the commercial production of pigeon eggs. Under controlled environmental conditions, no significant difference in egg weight between FM and FF pairings was observed, indicating that pairing pattern primarily affects egg production frequency rather than egg quality. In poultry, egg weight is a highly heritable trait primarily determined by genetics, maternal body weight, age, and nutritional provision (Penz Júnior and Jensen, 1991; Lin et al., 2016; Ding et al., 2025). While higher laying frequencies are typically associated with reduced egg weight, our data showed no such decline in the high-frequency FM group. We attribute this stability to the pigeon's naturally extended laying interval and adequate nutritional supply, which provide sufficient time and resources for the physiological deposition of yolk and albumen.

In commercial production, FF pairing may yield economic benefits by reducing male pigeon feed consumption while maintaining lower egg-laying frequencies. However, a limitation of the study is its 270-day observation period, which precludes definitive conclusions about long-term reproductive performance under FF pairing. Future research should employ extended observation windows to evaluate sustainability across multiple breeding cycles.

Birds can recognize various stimuli from their partners, including auditory (Cheng, 2008b; Szipl et al., 2014; Hernandez et al., 2016), behavioural (Faust and Goldstein, 2021; Wang et al., 2022), visual (Henderson et al., 2018), and olfactory cues (Jennings et al., 2022), which are known to activate the HPG axis and influence hormone secretion.

Under the agricultural production model, domestication has likely promoted continuous, year-round reproduction and tolerance to high-density rearing in pigeons. While individual cage housing reduces physical conflicts and predation pressure, the wire-mesh design subjects the birds to continuous visual and auditory stimuli from surrounding neighbors. Therefore, both direct partner interactions and the environmental effect jointly regulate pigeon hormones and behaviours, which ultimately influence their reproductive output.

We observed a significantly lower monthly egg production in FF pairing compared to FM pairing, consistent with existing literature: female ring doves paired with healthy, actively courting males exhibited better egg-laying performance and oviduct development compared to those paired with males that did not display courtship behaviour or had been castrated (Erickson and Lehrman, 1964; Friedman, 1977). In our study, we quantified six distinct behavioural patterns, among which courtship feeding and allopreening are particularly important for establishing and maintaining pair bonds (Nisbet, 1973; Kenny et al., 2017). The frequency of courtship feeding and allopreening in FF pairing was significantly lower than in FM pairing, which may contribute to a decline in egg-laying performance in FF pairing. In addition, we found that egg production performance in FF pairing was significantly positively correlated with the frequency of courtship feeding and allopreening. These findings suggest that the reproductive performance of female pigeons may be affected by behaviour and hormone secretion from their spouses. There were differences between the two groups in other non-interactive behaviours. FF pairing shows more frequent nesting behaviour, which may be related to the change of PRL secretion and may further inhibit egg-laying (Hu et al., 2025). Previous studies have confirmed that changes in external behaviour can typically influence hormone secretion, and hormones in turn can induce changes in behaviour (Ball and Balthazart, 2020). The neuroendocrine mechanisms underlying these behavioural effects are critical for understanding reproductive regulation.

In the study, we revealed a coordinated hormonal response following the first oviposition event, characterized by increases in FSH, LH, and E₂, and by a decrease in PRL. This endocrine profile aligns with established reproductive physiology, where elevated pre-ovulatory GnRH levels stimulate pituitary secretion of FSH and LH, which subsequently promote ovarian production of progesterone (P₄) and E₂. This mechanism promotes follicular development and ultimately leads to ovulation (Sharp et al., 1998; Dubois et al., 2002). After birds enter the incubation stage, PRL secretion typically increases gradually. In contrast, eggs were removed immediately after laying and did not enter a sustained incubation state in our experiment, which may result in a continuous decline in prolactin levels. This reduction in PRL secretion probably alleviates its inhibitory effect on the hypothalamic-pituitary-gonadal (HPG) axis, thus promoting the reactivation of reproductive cyclicity (Freeman et al., 2000). The secretion of reproductive hormones such as GnRH usually peaks several hours before ovulation (Miao et al., 2024). LI1 corresponds to the day after laying the first egg, while LI3 refers to the day after laying the second egg within the same clutch. Therefore, the typical pre-ovulatory surges of LH were not observed at LI1 and LI3. These two time points likely reflect the basal hormonal levels following oviposition. While upstream GnRH triggers this cascade, our measurements of the downstream hormones (FSH, LH, and E₂) provide direct insight into this follicular recruitment process. High levels of FSH and LH are critically required to maintain a high laying frequency (Prastiya et al., 2022). In contrast, the elevated PRL levels in FF pairing may be associated with their increased nesting behaviour, which could further suppress HPG axis activity and subsequent ovarian function.

The decline in FF pairing reproductive ability appears to be driven by a complex endocrine shift: diminished sociosexual stimulation from mates disrupts the normal temporal rhythms of the HPG axis, leading to abnormal early hormonal fluctuations (as seen at LI3) and prematurely elevated PRL levels at the late stage (LI7). This elevated PRL may further inhibits sustained gonadotropin secretion, ultimately delaying sustained follicular maturation and ovulation. By integrating behavioural and endocrine pathways, this study provides a systematic framework for understanding how pigeon sexual paring patterns affect reproductive efficiency and offers a theoretical basis for optimizing the same sexual mating system of female pigeons in commercial feeding.

Conclusions

In conclusion, this study demonstrates that female-female pairing pattern leads to a decline in individual egg-laying performance compared with female-male pairing. Female-female pairing showed a lower frequency of social behaviour (allopreening, courtship feeding) and a higher nesting frequency. These behavioural changes coincided with higher PRL levels in the late period of the egg-laying interval. Combined with previous studies, these results show that the intensity of pigeon mate interaction behaviour can affect the hormone secretion and egg-laying performance of female pigeons.

Declaration of generative ai and ai-assisted technologies in the writing process

During the preparation of this work, the author (s) did not use any AI and AI-assisted technologies.

CRediT authorship contribution statement

Ying Duan: Writing – review & editing, Writing – original draft, Visualization, Formal analysis, Data curation, Conceptualization. Cheng Chi: Visualization, Data curation. Kadirya Iskandar: Data curation. Mike Li: Data curation. Ali Hassan Nawaz: Writing – review & editing, Supervision. Shanjin Xu: Supervision, Resources. Runzhi Wang: Supervision. Yanqun Huang: Supervision. Chungang Feng: Writing – review & editing, Writing – original draft, Supervision.

Disclosures

The authors declare that they have no competing interests.