Mizoram is a small hilly state of India encompassing a total geographical area of 21,081 km². According to the Livestock Census (2019), the state had a goat population of 14,720, with the majority comprising non-descript goats.
       
Goats reared in Mizoram are predominantly characterized by small body size and low milk yield; however, they exhibit a remarkable capacity to adapt to diverse climatic conditions (Talukdar et al., 2023). In Mizoram, the indigenous non-descript goat population is widely recognized as Zokel and is also identified locally by names such as Kel, Mie and Meheh. For generations, these goats have formed an integral component of the traditional livestock system of tribal communities, including the Lushai, Lai, Hmar, Lakher and Paite groups (Lalhruaipuii et al., 2025). The body coat colour of this goat varies from black, white and brown, occurring either as solid colours or as mixed combinations of black, brown and white (Lalhruaipuii et al., 2025). It is characterized by a cylindrical body conformation and remarkable resistance to diseases. These goats are broadly distributed across the mountainous areas of Mizoram, which extends between 21^o56ʹ and 24^o31ʹ in North latitude and 92^o16ʹ and 93^o26ʹ in East longitude. Their population is relatively higher in the southern zone of the state, with the greatest concentration in Lunglei district, while lower numbers are recorded in Lawngtlai and Siaha districts (Lalhruaipuii et al., 2025).
       
Mizoram is predominantly characterized by rugged, mountainous terrain and a moderately temperate climate. Seasonal temperatures typically range from 8 to 21^oC during winter and from 21 to 33^oC in the summer months. The state receives a mean annual rainfall of approximately 2648 mm, although considerable regional variation exists, ranging from 1001 to 4462 mm annually. These goats are predominantly reared under an extensive production system. The rapid population growth, economic advancement, increasing income levels and shifting consumer preferences have collectively driven a growing demand for these goats as a valued source of palatable meat. Simultaneously, there is an essential need for greater understanding of sustainable genetic improvement and conservation programmes. Reproductive efficiency is a key economic trait in small ruminants, as it has a direct impact on the annual number of offspring produced (Greyling, 2000).
       
A comprehensive understanding of the reproductive anatomy of small ruminants is essential for attaining optimal reproductive performance. Morphometric evaluation of the female genital tract offers important insights into the reproductive health status and physiological condition of the animal. A detailed knowledge of the biometric parameters of the female genital tract is essential for carrying out reproductive procedures, including artificial insemination, pregnancy diagnosis and the effective management and treatment of infertility disorders (Kunbhar et al., 2003; Kumar et al., 2004). Advanced reproductive technologies designed to enhance population productivity, including in vitro fertilization (IVF) and artificial insemination (AI), also necessitate a comprehensive understanding of the biometric parameters of the female reproductive system (Cognié et al., 2003).
       
However, limited information is available regarding the morphometric evaluation of goat ovaries and other reproductive organs. Several studies have documented the physiology, morphology and pathological aspects of the reproductive organs in goats (Torres and Badiongan, 1989; Gupta et al., 2011). Nevertheless, information pertaining to the biometric evaluation of the reproductive tract in local goats of Mizoram remains very limited. It is essential to undertake studies focused on the characterization and conservation of this native goat population in order to facilitate dissemination of superior germplasm and improve the livelihoods of resource-poor farmers. Accordingly, the present study was undertaken to document the morphometric characteristics of normal reproductive organs and to generate baseline reference values for different segments of the genital tract in non-descript female goats native to Mizoram.

The twenty female goats were chosen from the local farms in and around Mizoram’s Aizawl region to study the reproductive habits of non-descript native female goats. Twenty female non-descript local goats that were Slaughtered at four abattoirs in the Aizawl area of Mizoram were used for the female genital biometry investigation.
       
Samples were collected from four designated abattoirs during routine slaughter procedures. The reproductive tracts of adult non-pregnant female goats were carefully collected, placed in sterile plastic bags and properly labelled. Initially, the samples were maintained under refrigerated conditions and then transported to the Department of Animal Reproduction, Gynaecology and Obstetrics, College of Veterinary Sciences and Animal Husbandry, Central Agricultural University, Selesih, Aizawl, Mizoram. On arrival, all specimens were stored at -20^oC until further analysis. Before examination, the frozen samples were thawed by immersion in cold water. A metric ruler, a thin flexible graduated steel tape, a weighing balance, a dissection tray and protective gloves were used for the morphometric evaluation of the specimens (Fig 1). All linear dimensions were measured in centimeters, whereas body weights were recorded in grams.


       
Each specimen was examined for the presence of any gross abnormalities. The reproductive tracts were thoroughly washed, freed from adherent connective tissues and arranged on a flat surface in their normal anatomical orientation (Fig 1). Morphometric measurements were recorded for different components of the genital tract, including the vulva, vagina, cervix, uterine body, uterine horns, oviducts and ovaries. Measurements were taken using a metric ruler, thread and a hand lens. The ovaries were excised by cutting the ovarian ligament as near to the ovarian tissue as possible, following detachment of the fimbriae. Ovarian length was measured along the line of excision at the attachment site of the ovarian ligament, while ovarian width was recorded as the greatest distance perpendicular to the longitudinal axis. Ovarian weight was assessed using an electronic balance. The number of follicles and corpora lutea in each ovary was enumerated under magnification using a magnifying glass (Singh et al., 1974). The length of each oviduct was measured in its fully extended state from the fimbrial end to the utero-tubal junction. Oviductal diameters were estimated from circumference measurements (Gupta et al., 2011).
       
The uterine horns were separated from their ligamentous supports and gently extended to their full length for accurate measurement. Each horn was then incised along the dorsal aspect to expose the lumen, extending from the utero-tubal junction up to the bifurcation of the uterine body. The uterine body was also opened along the dorsal aspect and the incision was extended caudally along a linear path up to the dorsal commissure of the vulva, allowing full exposure of the cervical canal and vagina. This method also enabled a comparative evaluation of the wall thickness of the uterine horns, uterine body, cervix and vagina. The uterine body length was recorded as the distance extending from the bifurcation of the uterine horns to the internal os of the cervix. Cervical length and overall condition were also recorded. Cervical length was measured as the distance between the internal and external os, whereas cervical diameter was derived from the circumference recorded at the mid-portion of the cervix. Vaginal length was measured from the external cervical os to the ventral commissure of the vulva. Vaginal width was recorded approximately 3 cm caudal to the external cervical os before the dorsal incision was extended through the vagina. Vulvar length was measured from the external opening of the vulva to the vestibule, whereas vaginal length was described as extending from the vestibule to the external cervical os (Drennan and Macpherson, 1966).
 
Statistical analysis
 
All the observations were systematically compiled and organized in tabular format. The recorded data were then entered into a Microsoft Excel spreadsheet and subjected to descriptive statistical analysis. A Student’s t-test (SPSS, version 21) was applied to determine the level of significance between measurements of the right and left side ovaries of the reproductive genitalia.

The oestrus behavioral signs like restlessness, standing, frequent bleating, tail wagging and frequent urination and physiological signs like vulvar swelling, vulvar reddening and cervico-vaginal discharge were observed visually in 100% of animals with other peri-oestral parameters like oestrus duration was recorded as 46.83 ± 3.17 hours. The present findings were similar with the findings of Chemineau (1986) and Chemineau et al. (1992).
       
The average vulva length of Mizoram’s non-descript native goats was 2.51±0.03 cm. The measurement of the vaginal length was 6.96±0.11 cm. The recorded dimensions of the cervix were 2.88±0.13 cm in length and 1.61±0.05 cm in width. The vulvar and vaginal length recorded in the current study were similar to the values described by Rahman et al. (1977) and Gupta et al. (2011) in Black Bengal goats. Nevertheless, the measurements reported by Sisson and Grossman (1972) and Adigwe and Fayemi (2005) were lower than present research. It was noted that the average vulvar length in the present study higher than the measurement reported by Adigwe and Fayemi (2005). The length of the cervix was found to be slightly greater than that reported by Sisson and Grossman (1972). In addition, the cervical breadth obtained in this study was somewhat higher than the value recorded by Adigwe and Fayemi (2005).
       
The average uterine body length and width of Mizoram’s non-descript local goats were 2.7±0.03 and 2.55±0.10 cm, respectively. In non-descript local goats of Mizoram, the uterine horn measured 13.69±0.53 cm in length and 2.80±0.42 cm in breadth. The average number of caruncles observed in the uterine horn was 57.5±1.20. A mean uterine caruncle number of 54.714±1.70 was previously documented by Gupta et al. (2011) in Black Bengal goats. The mean non-gravid uterine volume of non-descript local goats of Mizoram was 22.5 ml. The average uterine horn length observed in these goats was within the range of 10-12 cm, as reported by Sisson and Grossman (1972) in small ruminants. The present findings were comparable to those reported by Gupta et al. (2011) in Black Bengal goats. Adigwe and Fayemi (2005) reported comparatively higher values. The breadth of the uterine horn in non-descript local goats of Mizoram exceeded the measurement described by Adigwe and Fayemi (2005) in Sokoto goats of Nigeria. The average uterine body length in the present study was almost similar to the value reported by Sisson and Grossman (1972), although it was lower than that recorded by Adigwe and Fayemi (2005). These findings were comparable to those reported by Gupta et al. (2011) in Black Bengal goats. The average length of the oviduct of non-descript local goats of Mizoram was 10.42±0.41 cm. The present finding was lower than the value reported by Adigwe and Fayemi (2005). The present finding was similar with Gupta et al. (2011) in Black Bengal goat.
       
The average length, breadth, weight, follicular count and number of corpora lutea (CL) per ovary in non-descript local goats of Mizoram are summarized in Table 1. The ovaries of adult goats were found to be almond-shaped. The mean length of the right ovary was higher than that of the left ovary (Table 1). The present observations were similar to those described by Gupta et al. (2011) in Black Bengal goats. Lower ovarian lengths for both ovaries were reported by Islam et al. (2007). On the other hand, higher ovarian lengths compared with the current findings were documented by Mahammadpour (2007) in Iranian native goats, Adigwe and Fayemi (2005) in Maradi goats of Nigeria and Sharma and Sharma (2004) in Gaddy goats of India. The average ovarian weight recorded in this study was similar to that reported by Gupta et al. (2011), although lower than the values reported by Islam et al. (2007). The mean follicular count on the surface of each right and left ovary exceeded the values documented by Islam et al. (2007). Significant differences (P<0.05) were observed in the number and diameter of corpora lutea (CL) between the right and left ovaries, with the right ovary containing more CL and larger CL diameters. No genital abnormalities were observed in the non-descript local goats of Mizoram examined in the current study.


       
The discrepancies between the present results and earlier published reports in goats might be associated with breed-related variations. Differences in genital tract dimensions may additionally result from environmental influences, since young goats in tropical climates frequently face the impact of the first dry season, during which growth can be severely restricted. As most available studies involve Jamnapari, crossbred and local goats, elucidating the causes of variation among breeds and species is important for improving the understanding of reproduction in these animals.

The present investigation revealed that the right ovary of non-descript native goats in Mizoram was broader, longer and heavier than the left ovary, thereby supporting the notion that the right ovary exhibits greater activity than the left. These findings have established baseline dimensions for the different segments of the female reproductive tract of non-descript native goats of Mizoram and the data may assist in the diagnosis of various abnormalities.

The authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish, or preparation of the manuscript.