The Reproductive Implementation of Azakheli Buffalo Breed Inference of Khyber Pakhtunkhwa in Swat Pakistan
Khan SU, Qadir A, Salim M, Khan M, Saleem M, Ullah F and Ahmad S
Published on: 2024-04-01
Abstract
The current research was conducted to interpret the reproductive characteristics of the Azikheli buffalo in the home tract of the breed Swat Valley, Pakistan. The mean pubertal age of Azikheli buffalos recorded was 1147.93±13.05 days, and the highest percentage of buffalos (44.89%; n = 202) was observed in pubertal age ranging from 811-1081 days with a mean pubertal age of 1048.81±4.87 days. The mean postpartum estrus interval in Azikheli buffalo observed was 147.56±5.64 days. A highly significant (b = -0.026±0.0044; F (1, 2) = 30.59; p = 0.03) reduction in the mean postpartum anestrus interval was observed as parity increased from first to fourth. Similarly significant (b = - 9.143±1.87; F (1, 2) = 23.77; P = 0.0396) effect of season on postpartum anestrus interval was also observed, with the longest postpartum anestrus interval in the autumn season and the shortest in the summer season. The percentage of Azikheli buffalo conceived after the first service was 64.33 percent. The mean calving interval observed in Azikheli buffalos was 489.16±5.82 days. A highly significant (b = -0.021±0.001; F (1, 2) =213.09; P = 0.004) reduction in mean calving interval was noted as the parity number advanced from first to fourth. The effect of season on the calving interval was statistically not significant. The mean dry period observed was 119.47 ± 2.58 days. A highly significant (b = -0.049±0.0100; F (1, 2) = 24.56; P = 0.03) reduction in mean dry period was observed as parity increased from first to fourth. However, no significant effect of season on the dry period was observed (P > 0.05). The calf sex ratio observed in Azikheli buffalo was 100: 89
. There was no significant effect of parity on the calf-sex ratio. Season significantly (χ2 (1) = 3.985; P = 0.045) affects the calf sex ratio, with more male births in the autumn compared to the spring season. The mean birth weight of male calf observed in this study was 33.42±0.67 kg. Male birth weight in parity second was significantly higher than in first parity (t (33) = 2.26511; P = 0.03) and third parity (t (32) = 3.2725; P = 0.002). No significant (F (3, 46) =0.285456; P = 0.83) differences in male birth weight were found in calves born in different seasons of the year. The mean birth weight of a female calf was 29.67±0.75 kg. No significant effect of parity (F (2, 46) =2.54; P = 0.08) and season (F (3, 45) =0.234732; P = 0.87) was observed on female calf birth weight. Male calves were significantly (t (97) =3.71; P = 0.0003) heavier than female calves at birth. The current study illuminated the basic reproductive physical characteristics of the local Azikheli buffalo in their home tract.
Keywords
Azakheli buffalo; Khyber pakhtunkhwaIntroduction
This study on physical and morphometric characteristics, productivity, and reproductive performance was carried out on Azikheli buffalos and bulls in Khwazakhela, District Swat, and Khyber Pakhtunkhwa, Pakistan. Various physical characteristics studied included color patterns of the coat, forehead, eyelashes, eyes, horns, muzzle, forelegs, hind legs, and hooves of Azikheli buffalos and bulls. Morphometric measurements included heart girth, body length, height at wither, height at hipbone, head region (face length, ear length, and width), horn, neck, back, rump, legs, and tail. Parameters for reproductive performance were pubertal age, postpartum anestrus interval, conception efficiency, calving interval, and dry period.
Pakistan is endowed with rich livestock genetic resources that are well adapted to the local conditions. There are 15 breeds of cattle, 5 breeds of buffalo, 33 breeds of sheep, and 36 breeds of goat [1-8]. The population of cattle in Pakistan is 29.56 million, buffalo 27.33 million, sheep 26.49 million, and goats 53.79 million [1]. There are 177.247 million buffalo heads worldwide in 50 countries, of which 171 million (97%) are found in Asia, while 5.38 million (3%) are found in the rest of the world. Pakistan, with a population of 29.9 million (14%) is the second-highest buffalo-inhabited country in the world after India, which has a population of 98.7 million (56 % of the total world buffalo) [8-11]. Buffalo is the second-largest (75 million tons) source of milk supply in the world [12].
Local indigenous breeds, those adapted to the harsh environment of developing countries, have not yet been sufficiently characterized, and in the case of their extinction, the value lost to humankind is not known [13]. It is, therefore, necessary first to evaluate local breeds for phenotype, special characteristics, performance, performance potential, and crossbreed suitability, especially in their home tracts and under existing management conditions [14]. Traditionally, external or internal phenotypic characters have been adopted to ascribe a given animal to a breed [15]. Phenotypic and genetic characterization of populations, breeds, and species is essential for the development of appropriate breeding strategies, sustainable use of genetic diversity, genetic conservation, and assessment of genetic variability [16,17] and thus the variations at the molecular level are based on the phenotypic variations among breeds [7]. Phenotypic as well as adaptive characteristics are important in identifying breed attributes for immediate use by farming communities [18]. The commonly used phenotypic characteristics are the morphological (physical and morphometric), productive, reproductive performance, birth, and adult body weight of the animals.
Indigenous breeds that have been evolved and adapted from time immemorial and exist with their own genetic makeup are disappearing by dilution and replacement [19] because of new market demand, use of new breeding technology (FAO, 1992) changes in the socio-economic environments of a region [20] and modern production techniques [21]. Indigenous breeds were considered inferior to exotic and crossbred animals, but with the passage of time, the performance of indigenous breeds reported was equal to or even better than that of exotic, improved, or crossbred animals [22]. In the production system of harsh environmental conditions, the performance of local indigenous breeds is better than that of exotic breeds in terms of productivity [23,24]. Although the output is low, the inputs required are also low, hence providing better financial returns to the farmer (Scarpa et al., 2003). Indigenous breeds are mainly kept in low-input, low-output production systems [13], are hardy, disease-resistant, survive on little water, scanty vegetation, have tasty meat, and have good adaptability to various environments where modern imported exotic breeds are unable to exist [25,26] (FAO, 2010). Some pictures of Azkheli buffalo are given in Figure 1.
Figure 1: Azakheli Buffalo Breed Various Position of Nature.
Reproductive Performance
Milk production in buffalo is an economically important trait that contributes 12.5% of the total annual world milk production and provides milk to 50 countries around the world [27,28]. In Asia, 40% of milk (74.5 million tons) is obtained from buffalo [27,28]. On the other hand, in Italy, buffalo has sustained a powerful dairy industry [27]. In Pakistan, 29.9 million buffalo provide 62 percent of milk in the country [11]. Estimation of milk yield is useful for dairy producers in making management and breeding decisions and is essential for genetic evaluation [29-31].
Successful reproductive performance is a critical component of profitable dairy enterprises [32] as it affects the amount of milk production per animal per day of herd life [33,34]. Increased herd longevity [35,36] availability of replacement stock [37], and more selective culling and replacements are also associated with reproductive success. Reproductive performance influences the amount of milk produced per animal per day of herd life, breeding, rate of culling, and rate of genetic improvement for the traits of economic importance [37-39]. Reproductive performance is influenced by various factors like milk production [40,41] parity [42-44], season [44], nutrition [45], and diseases [46]. There are several indices, like first-service conception rate and calving interval, that can be used to evaluate reproductive efficiency and fertility in dairy animals [47], and no single trait can adequately summarize reproductive performance [48]. As far as fertility is concerned, the distribution of data is not always normally held, and the traits are expressed differently during life. Traditional measures of fertility are used for assessing fertility [49], as reliable physiological measures associated with the inherent fertility status of dairy animals are not available. The reasons are of a practical nature, e.g., multiple measurements per dairy animal during a certain period are required, or the tests or analyses are too expensive to be used on a large scale. Methodically, fertility measures can be divided into two categories, i.e., interval measures and fertility scores. Interval measures are days from calving to first service or heat (postpartum anestrus interval), days open, and calving interval [50]. Fertility scores include non-return to first service and conception at first service. Non-return to the first service is determined by whether another service follows within predetermined days of 56 or 90 days. Reproductive traits of major importance are pubertal age, postpartum anestrus interval, percentage of pregnant buffalo to various numbers of natural services, calving interval, and dry period.
Pubertal Age
In dairy animals, puberty has been defined as the age at first standing estrus and is characterized by the first ovulation [51,52]. The attainment of puberty is the fine adjusting of central and local endocrine balance and its relationship to the cellular events taking place in the organs of the reproductive tract (Presicci, 2007). Pubertal age is considered an important determinant of reproductive efficiency, and for optimum reproductive performance, an early attainment of puberty is of prime importance [53,54]. It is generally recognized that buffalo heifers have delayed puberty, and the age at which riverine buffalo heifers attain puberty can be highly variable. Many factors influence age at puberty, such as breed, season, climate, nutrition and growth rate, body condition score, and the period of the year at which the animal is born [54-58] and male and female bio-stimulation [59]. Raising heifers is the most expensive component of dairy farm operations, but with better feeding and management, pubertal age can be reduced to 2 years [60].
Postpartum Anestrus Interval
The interval from calving to first estrus is known as the postpartum estrus interval [61,62]. Prolonged postpartum acyclicity and anestrus or subestrus are major sources of economic loss for buffalo dairying. To maintain a calving interval of 13-14 months in buffalo, these events must be accomplished by 60-80 days after calving, with successful breeding occurring within 85-115 days. Hormonal changes during the peri-parturient period, besides regulating lactogenesis and parturition, also have an impact on postpartum reproductive activity [63]. Puerperal uterine soundness is essential for the early establishment of postpartum estrus cyclicity [64]. Postpartum anestrus interval may be affected by several factors such as breed, nutritional plan, milk yield, suckling, uterine involution, and season of calving [65-71]. As far as the effect of parity is concerned, a significant decrease in the postpartum anestrus interval with increased parity order has been reported [72-74]. However, the non-significant effect of parity was also noted by [75-77] in buffalo. The influence of the season of calving on the postpartum anestrus interval has been studied by various workers. Significant effects of season on postpartum anestrus interval have been reported in Kundi buffalo [78], Surti buffalo [79], and Brazilian buffalo [80]. On the other hand, [81] reported a non-significant effect on the trait in Mensoni buffalo, Nili-Ravi buffalo, and Egyptian buffalo, respectively.
Conception Efficiency
According to conception efficiency can be measured by the percentage of animals conceived for the first, second, third, and greater than third service, and the first service conception rate is most widely used in this regard [82]. The first-service conception rate is an important index that measures the ability of the animal to become pregnant after first service and provides a useful estimate of the conception rate for a herd. It is the combined consequence of all events, from fertilization to fetal development [83]. Various factors influencing conception rate in buffalo are breeding time [84-86], body score condition [87], disease [88-90] embryonic death [91-94], Cyclic and non-cyclic ovarian condition Season parity and inherent characteristic [95-102].
Calving Interval
Calving interval in dairy animals is defined as the duration between two consecutive calvings [103,104]. An ideal calving interval of 12-14 months in buffalo is desirable, whereas a longer or shorter calving interval is unprofitable [105]. The Calving interval is one of the most important parameters to evaluate the productive and reproductive efficiency, economic value, and number of calves by lifetime in a farm or in a population [106-107]. Buffalo has an inherent susceptibility to environmental stress, which causes anestrus and sub-estrus that are responsible for a prolonged calving interval, resulting in great economic loss for the buffalo dairy industry [108]. Various factors affecting calving interval are season, parity, and year of calving. Regarding the effect of season on calving interval, both significant and non-significant effects have been reported in the literature reported a significant effect of season on calving interval in Venezuela buffalo, Murrah buffalo, and Nili-Ravi buffalo, respectively, whereas in Murrah buffalo [109,110]. and reported a non-significant effect of season on calving interval. Parity has also been observed as a significant source of variation in calving interval in Murrah buffalo reported a non-significant effect of parity on calving interval in Mehsana buffalo [111-114].
Dry Period
The dry period is a non-lactating period incorporated between successive lactations and is vital in dairy buffalo for the recoupment and replacement of exhausted lacteal tissues [104]. It allows the mammary epithelial component to regress, proliferate, and differentiate, which in turn allows maximal milk production to occur during the subsequent lactation [115,116]. The dry period influences lifetime milk production and is a necessary management practice to maintain profitable milk production in dairy animals [117,118]. In dairy buffalo, the dry period has a marked influence on the replacement rate and cost of milk production. The dry period in buffalo is influenced by various factors, including genetic [119-123] parity and season [124,125]. The significant effect of parity on dry periods was reported by in Murrah buffalo and in Surti and Mehsana buffalo. However, reported a nonsignificant effect of parity on the dry period in Swamp buffalo. Similarly, a significant effect of the calving season was reported on the dry period in Murrah buffalo. However, a non-significant effect of the calving season on the dry period was also reported in Nili-Ravi buffalo in Pakistan [126].
Calf-Sex Ratio
To exploit the production potential of any species of domestic animals, basic information regarding different reproductive parameters such as ovarian activity, cornual implantation, and sex ratio is of prime importance Several attempts have been made to increase the frequency of a desirable sex in animals without much success [127]. If the frequency of a desirable sex is increased, then genetic gain can be maximized through increased intensity of selection [128]. Parity, season, month, year, and sire vary non-significantly in buffalo calf sex ratio and sex determination is controlled by genetic factors [129].
Birth Weight
From an economic point of view, birth weight in dairy animals is one of the most important factors, as it is directly correlated with weight at maturity and can be used as a measure for effective selection. Birth weight is a measure of growth rate and is the first component that can be easily evaluated [130,131]. Birth weight is influenced by breed [132], sex, parity [133], and season. Rao and Rao (1996b) and Naqvi and Shami (1999) reported a significant effect of parity on calf birth weight in Murrah and NiliRavi buffalo, respectively. Chantalakhana et al. (1984) reported a significant effect of season on calf birth weight in Swamp buffalo, whereas Zaman (1996), Singh et al. (2003), and Das et al. (2004) reported a non-significant effect of season on calf birth weight in Swamp buffalo in Thailand, Swamp buffalo in Asam in India, and Swamp buffalo in Assam in India, respectively.
In Pakistan, the most studied buffalo breeds are Nili-Ravi and Kundi, and 37% of the buffalo population (10.13 million) is non-descript [3]. Although these buffalo breeds have been considered non-descript, they are highly adapted to the environmental conditions of the area and have great potential. Azikheli is a buffalo breed in Swat that is acclimatized to the local conditions and is reared by farming communities. Only introductory information about the breed is available, emphasizing the scientific characterization of the breed [134]. It is an important indigenous animal genetic resource in the area and got its name from its original home tract called Azikheil, one of the several tributary valleys of the Swat. The broader home tract includes the watersheds of River Swat (District Swat) and River Panjkora (District Lower and Upper Dir), District Shangla, Bunair, and Malakand agencies. Pockets of the breed can also be found in District Mardan, Charsadda, Nowshera, and Sawabi because of transhumant migration during the winter season from upland pastures in District Swat and Dir. This breed needs characterization, description, and improvement for sustainable future use in the adapted area. The present investigation is thus designed to study the Azikheli buffalo breed with the objective of studying the reproductive performance of Azikheli buffalo under traditional management systems.
Materials And Methods
Study Area
Swat Valley is situated at 34.4° and 35° North and 72° and 74.6° East. It covers an area of 8220 square kilometers, and the elevation above mean sea level varies from 600 meters in the south to 6000 meters in the north, with a human population of 12,49,572 [135]. There are two main rainy seasons: from the end of December to the end of April and from the end of July to mid-September, and the annual precipitation in Azikheil has a range of 1000-1750 mm per year. July is the hottest month, and January is the coolest month of the year. The temperature is, however, not uniform and inversely varies with increasing elevation; however, it never goes above 38 °C and below -10 °C. The two main dry seasons are from the end of May to mid-July and from the start of October to the end of November. Such enormous spatial and temporal seasonal variation compels the residents to evolve a complex farming system and settlement pattern based upon the provisions of relief, climate, and labor requirements for obtaining a particular amount of output from a unit of natural resources [136]. Khwazakhela Valley (Azikheil) of Swat District was selected as the study area, which is a central location in the original home tract of the Azikheli buffalo (Fig. 1). This is one of the most fertile valleys in Swat and lies about 20 kilometers from Mingora, the headquarter of Swat district. The valley is almost 30 kilometers long and 20 kilometers wide. Major crops are wheat, rice, and maize, whereas apples, fersimen (Dyospirus kaki), and shaftalo (Prunus persicum) are the main orchards. Different ethnic groups mostly occupy different ecological niches or units; hence, landowners are dominant in valley bottom, tenants on hill slopes and hilltops with cropping potential, and Gujar (settled livestock herders with cattle and buffalo herders; Ur-Rahim and Viaro, 2002) at hill slopes and hilltops with grazing potential. This stratification, however, is not a strict or watertight compartment, and tenants and gujars may be present in specific locations at the valley bottom and landowners at hill slopes and hilltops. For this study, the seasons were classified as autumn (September October, temperature 24-26 oC), winter (November-February, temperature zero to minus eight oC), spring (March-April, temperature 22-24 oC), and summer (May-August, temperature 21-38 oC; Urdu Tourists Guide).
Reproductive Performance
Data on reproductive performance of Azikheli buffalo were collected from farmers rearing Azikheli buffalo, randomly selected through pre-designed, tested questionnaires (annexure). Data were grouped according to parity and season for the study of both of these effects. The low number of records for the season effect was due to the unavailability of information on the calving season of the buffalo cows. Data collected for pubertal age was recorded on 450 buffalo cows. For the postpartum estrus interval, 483 buffalo cows were recorded for the parity effect and 388 buffalo cows for the season effect. Buffalo cows recorded for the percentage of pregnant buffalo cows were 429 in number. Data on calving interval for the parity effect was based on 303 buffalo cows and for the season effect on 278 buffalo cows. Information on dry periods was obtained from 445 buffalo cows for the parity effect and 364 buffalo cows for the season effect. The following reproductive traits were recorded.
Pubertal Age
The pubertal age in Azikheli buffalo was taken as the age at first estrus based on bellowing and mucus discharge from the vulva, and a pubertal age of 450 buffalo was available for analysis in the present study.
Postpartum Anestrus Interval
The postpartum anoestrus interval was considered the interval from calving to the first observed estrus. On a parity basis, the mean postpartum anoestrus interval for the present study was recorded for 483 buffalo cows, with 194 buffalo cows between first and second parity, 211 buffalo cows between second and third parity, 66 buffalo cows between third and fourth parity, and 12 buffalo cows between fourth and fifth parity. Data was also grouped according to calving season, and a postpartum anoestrus interval of 365 buffalo cows was thus available for analysis, with 73 buffalo cows calving in the spring season, 233 in the summer, 29 in the autumn, and 53 in the winter season.
Conception Efficiency
Conception efficiency of Azikheli buffalo cows was calculated as the number of Azikheli buffalo cows conceived for any number of services (first, second, third, fourth, and more than fourth (fifth and sixth)) divided by the total number of buffalo cows provided with natural service × 100 (Fetrow et al., 1990) and expressed as the percentage of Azikheli buffalo cows conceived after availing of first, second, third, fourth, and more than fourth (fifth and sixth) natural services. Data for 429 Azikheli buffalo cows was available for this trait.
Calving Interval
The calving interval was taken as the interval between the last two successive calvings. On a parity basis, the mean calving interval for the present study was calculated for 303 buffalo cows, with 144 buffalo cows between first and second parity, 102 buffalo cows between second and third parity, 45 buffalo cows between third and fourth parity, and 12 buffalo cows between fourth and fifth parity. Data was also grouped according to calving season, and a calving interval of 278 buffalo cows was thus available for analysis, with 50 buffalo cows calving in the spring season, 169 in the summer, 23 in the autumn, and 36 in the winter season.
Dry Period
The dry period was taken as the non-lactating period between the last two successive calvings. On a parity basis, the mean dry period for the present study was calculated for 445 buffalo cows, with 183 buffalo cows between first and second parity, 190 buffalo cows between second and third parity, 60 buffalo cows between third and fourth parity, and 12 buffalo cows between fourth and fifth parity. Data was also grouped according to calving season, and a calving interval of 364 buffalo cows was thus available for analysis, with 66 buffalo cows calving in the spring season, 223 in the summer, 26 in the autumn, and 49 in the winter season.
Calf-Sex Ratio
Sex of 507 calves, including 108 calves born to buffalo cows registered for milk yield recording, and 399 calves recorded during farmer interviews through a questionnaire for reproductive performance were used to calculate the calf sex ratio. On a parity basis, the sex ratio for the present study was calculated for 507 buffalo calves, with 209 buffalo calves between first and second parity, 198 buffalo calves between second and third parity, 89 buffalo calves between third and fourth parity, and 11 buffalo calves between fourth and fifth parity. Data was also grouped according to calving season, and a calving interval of 507 buffalo calves was thus available for analysis, with 83 buffalo calving in the spring season, 304 in the summer, 54 in the autumn, and 66 in the winter season.
Statistical Analysis Means
The standard error and Student’s t-test were calculated for various comparisons. The chi-square test and analysis of variance were also performed using GraphPad Prism-5 (GraphPad Software, San Diego, CA).
Results
This study was carried out on 618 Azikheli buffalo and bulls. The recorded parameters were morphological characteristics, milk production, and reproductive performance. The morphometric characteristics of 135 Azikheli buffalo and bulls were studied. Reproductive performance included pubertal age (n = 450), postpartum estrus interval (n = 483), percentage of Azikheli buffalo conceived after various natural services (n = 429), calving interval (n = 303), and dry period (n = 445).
Reproductive Performance
Reproductive traits studied were pubertal age, postpartum anoestrus interval, conception efficiency, calving interval, and dry period.
Pubertal Age
The mean pubertal age of the Azikheli buffalo observed in this study was 1147.93±13.05 days, ranging from 540 to 1800 days. Pubertal age was divided into five groups with an interval of 270 days (Table 1) (16). The lowest percentage of buffalo reached puberty at an early age, ranging from 540 to 810 days. The highest percentage (44.89%; n = 202) of buffalo reached pubertal age, ranging from 811 to 1081 days with a mean of 1048.81±4.87 days. Those buffalo who take a longer time to reach pubertal age were very small in number. The minimum and maximum age at maturity recorded in this study were 540 days and 1800 days, respectively. The mean pubertal age of this buffalo ranged from 704.57±7.41 days to 1788.46±7.99 days (Table 1) (16).
Table 1: Pubertal age (days) of Azikheli buffalo in Khwazakhela valley of District Swat, Khyber Pakhtunkhwa, Pakistan.
Pubertal Age in Azikheli Buffalo (Days) |
|||
Range |
Mean+SE |
Number |
Percentage |
540-810 |
704.75±7.41 |
61 |
13.56 |
811-1081 |
1048.81±4.87 |
202 |
44.89 |
1082-1352 |
1191.17±7.93 |
68 |
15.11 |
1353-1623 |
1443.23±2.53 |
93 |
20.67 |
1624-1894 |
1788.46±7.99 |
26 |
5.78 |
Postpartum Anoestrus Interval
Overall sample: A postpartum anoestrus interval of 483 buffalo was recorded. The overall mean postpartum anoestrus interval was 147.56± 5.64 days, which ranged between 10 and 570 days. The postpartum anoestrus interval was divided into seven groups with an interval of ninety days. The longest mean postpartum anoestrus interval (560.00±5.00 days) was noted in the postpartum anoestrus interval ranging from 546 to 636 days. The highest percentage of buffalo (50.10%, n = 242) with a mean postpartum anoestrus interval of 51.80±1.76 days was observed in the postpartum anoestrus interval ranging from 10-90 days (Table 2) (17).
Table 2: Postpartum Anoestrus Interval of Azikheli Buffalo in Khwazakhela Valley of District Swat, Khyber Pakhtunkhwa, Pakistan.
Postpartum Anoestrus Interval (Days) |
|||
Range(days) |
Mean+SE |
Number |
Percentage |
Up to 90 |
51.80±1.76 |
242 |
50.1 |
91-181 |
153.46±02.49 |
117 |
24.22 |
182-272 |
225.75±03.03 |
40 |
8.28 |
273-363 |
358.71±00.95 |
70 |
14.49 |
364-454 |
474.64±17.34 |
14 |
2.9 |
Conception Efficiency
Conception efficiency based on the percentage of Azikheli buffalo conceived after availing of first, second, third, fourth, and more than fourth natural (fifth and sixth) services is shown in Table (3)20. The highest percentage of Azikheli buffalo conceived was after the first service, whereas buffalo who conceived after three services were only 5.83 percent. Regression analysis of variance shows no significant differences in these percentage reductions of pregnant buffalo from first to fourth and above services (b = - 0.01±0.003, F (1,2) = 9.31; P = 0.09) (Table (4) 21).
Table 3: Number and Percentage of Azikheli Buffalo Conceived After Various Number of Natural Services in Khwazakhela Valley of District Swat, Khyber Pakhtunkhwa, Pakistan.
Percentage of Pregnant Buffalo |
|||
1st service |
2nd service |
3rd service |
and more than 4th (5th and 6th) service |
No- % |
No- % |
No-% |
No-% |
276-64.33 |
105-24.47 |
23-5.36 |
25-5.83 |
429* |
*Total number of pregnant buffalo conceived |
Table 4: Regression analysis of variance showing differences in percentage of pregnant Azikheli buffalo after first, second, third, fourth, and above services in Khwazakhela valley of District Swat, Khyber Pakhtunkhwa, Pakistan. b=-0.00986±0.00323.
Source |
df |
SS |
Ms |
F |
P |
Regression |
1 |
4.11 |
4.11 |
9.31 |
0.9 |
Residual |
2 |
0.88 |
0.44 |
|
|
Total |
3 |
5 |
|
|
|
Calving Interval
Overall Sample
The Calving interval was recorded in 303 Azikheli buffalo. The overall mean calving interval was 489.16±5.82 days, which ranged between 345-750 days. The Calving interval was divided into five groups with an interval of ninety days. The highest percentage of buffalo (35.31%; n = 107) with a mean calving interval of 396.16±2.18 days was observed in calving intervals ranging from 340 to 430 days (Table 5). The highest mean calving interval was in the range of 704-794 and the lowest was in the range of 340-430 days.
Table 5: Calving Interval of Azikheli Buffalo in Khwazakhela Valley of District Swat, Khyber Pakhtunkhwa, Pakistan.
Calving Interval (days) |
|||
Range |
Mean±SE |
Number |
Percentage |
340-430 |
396.16±2.18 |
107 |
35.31 |
431-521 |
471.73±2.38 |
106 |
34.98 |
522-612 |
545.83±2.96 |
42 |
13.86 |
613-703 |
677.5±2.01 |
40 |
13.2 |
704-794 |
727.5±4.91 |
8 |
2.64 |
Table 6: Regression Analysis of Variance Showing Differences in Mean Calving Interval in First, Second, Third, and Fourth Parity of Azikheli Buffalo in Khwazakhela Valley of District Swat, Khyber Pakhtunkhwa, Pakistan.
Source |
df |
SS |
Ms |
F |
P |
Regression |
1 |
4.9535 |
4.9535 |
213.09 |
0.005 |
Residual |
2 |
0.0464 |
0.0232 |
||
Total |
3 |
5 |
Dry Period
Overall Sample
A dry period was recorded in 445 Azikheli buffalo. The overall mean dry period was 119.74±2.58 days, ranging from 10-255 days. Ranges for the dry period, their mean, and percentage are given in Table 7. The dry period was divided into nine groups with an interval of thirty days. The highest percentage of buffalo (25.74%; n = 115) was observed in the dry period, ranging from 93 to 123 days with a mean of 105.66±0.28 days (Table 7) 26). The minimum dry period was 10 days, and the maximum dry period was 255 days.
Table 7: Dry Period (Days) of Azikheli Buffalo in Khwazakhela Valley of District Swat, Khyber Pakhtunkhwa, Pakistan.
Dry Period (days) |
|||
Range |
Mean±SE |
Number |
Percentage |
Up to 30 |
24.41±1.97 |
16 |
3.6 |
31-61 |
50.00±1.02 |
52 |
11.69 |
62-92 |
78.85±0.76 |
74 |
16.63 |
93-123 |
105.66±0.28 |
115 |
25.84 |
124-154 |
135.83±0.40 |
72 |
16.18 |
155-185 |
165.94±0.52 |
49 |
11.01 |
186-216 |
195.32±0.46 |
34 |
7.64 |
217-247 |
225 |
22 |
4.94 |
248-278 |
255 |
11 |
2.47 |
Sex Ratio
Overall Sample
The overall sex ratio of male and female calves of Azikheli buffalo recorded was 100: 89
. The differences between the two sexes are not significant (χ 2 (1) = 1.66; P ≈ 0.20).
Discussion
Azikheli buffalo is an indigenous breed of District Swat, Khyber Pakhtunkhwa. Very little information is available on the phenotypic, productive, and reproductive characteristics of this breed. The present study was conducted to investigate some of the reproductive performance of Azikheli buffalo in District Swat, Khyber Pakhtunkhwa. Reproductive traits included pubertal age, postpartum anestrus interval, conception efficiency, calving interval, and dry period.
Data on reproductive performance, including pubertal age, postpartum anestrus interval, conception efficiency, calving interval, and dry period, were collected from farmers through a questionnaire, and these questionnaire-based results are discussed in the following paragraphs. The pubertal age of animals is an important determinant of reproductive efficiency, and early attainment of puberty is necessary for optimum reproductive performance. It provides the availability of replacement stock [137], which creates opportunities for more selective culling and allows the herd to sell replacements (Evans et al., 2006; Chang et al., 2006). The mean pubertal age of Azikheli buffalo recorded in this study was 1147.93±13.05 days, and the highest percentage of buffalo (44.89%) was observed in pubertal age ranging from 811-1081 days with a mean pubertal age of 1048.81±4.87 days (Table 1). It is evident from this study that Azikheli buffalo attain puberty at a later age as compared to Mediterranean buffalo (603.7 days) [138], Swamp buffalo (720 days) [139], Asian Buffalo (720 days) [140], Nili-Ravi buffalo (1110 days; Bashir, 2006; 1020 days; 1044±171 days) [141] and Indian buffalo (1080 days; Ingawale and Dhoble, 2004). Late pubertal age in buffalo has been attributed to poor nutrition (Akhtar et al) [142] and poor management [143,144]. Individual selection of buffalo and better nutrition can reduce pubertal age in buffalo [145]. Longer pubertal age than the present study has been reported in Gaddi buffalo (1368 days) [146] and Bangladeshi buffalo (1411.58±43.01 days) [147] Prolonged postpartum anestrus interval is a major source of economic loss to buffalo breeders [148,149] hence, early return to ovarian cyclic activity is a prerequisite for high reproductive efficiency [150]. To maintain a calving interval of 13-14 months in buffalo, resumption of anestrus postpartum must be accomplished by 60-80 days, with successful breeding occurring within 85-115 days [151]. The overall mean postpartum anestrus interval in Azikheli buffalo observed was 147.56±5.64 days in this study. A longer postpartum anestrus interval than the present study was reported in Nili-Ravi buffalo in Pakistan (183.42±2.37 days, 176.73±2.71) [152,153]. Indian Murrah buffalo (178 days) [154] and Bangladeshi buffalo (179.32±10.31 days [147]. But others had reported lower values for postpartum anestrus interval than the present study in Nili-Ravi buffalo (124±14.58 days, 52.22±4.12 days, 69.03±6.03 days) [155-157]. Surti buffalo in India (126 day) [158]. Sri Lankan Murrah buffalo (133±91 days) [159]. Anatolian buffalo (15-82 days) [160] and Egyptian buffalo (18-65 days) [161]. The postpartum anestrus interval observed in this study ranged from 10-570 days (mean: 147.56±5.64 days). A wide range of 11-526 days [162], 21-749 days [163], 30-750 days [164], and 21-915 days [165] have been reported for the post-partum anestrus interval in the Nili-Ravi buffalo in Pakistan. It was observed in the present study that 50.10% of Azikheli buffalo showed estrus up to 90 days postpartum. Ahmad et al. (1981) reported 49% of Nili-Ravi buffalo showing estrous up to 90 days post-partum. However, in Egyptian buffalo (34%, Youssef et al., 1988) and Indian Murrah buffalo (45%, Shrivastava and Kharche, 1986), lower percentages of buffalo were observed to show estrus up to 90 days post-partum than in the present study. In this investigation, 24.22% of Azikheli buffalo were observed to show estrus from 91-181 days post-partum. In the literature, it has been reported that 24% of the Egyptian buffalo (Youssef et al., 1988), 55% of the Indian Murrah buffalo [166] and 20% of the Nili-Ravi exhibit estrus, which ranges from 91-150 days postpartum. This wide variation in post-partum anestrus interval might be the effect of limited suckling and non-suckling practices, inadequate estrus detection, or failure to detect estrus and nutrition [167-171]. A highly significant (P = 0.02) reduction in the mean postpartum anestrus interval was observed in the present study. These differences in the post-partum anestrus interval might be due to differences in the environment, management, and breed of buffalo [155]. According to Mohammed and Jayaruban (1991), variation in climatic conditions has a direct effect on the physiological functions of the animal and indirectly affects the availability of required nutrients (Mohammed and Jayaruban, 1991). Sometimes the anestrus interval is prolonged due to sudden climatic variation, such as a fall in temperature, exposure to cold wind, or heavy rain associated with low temperatures or hot weather, without any possibility of bathing or sheltering from the sun [172]. Apart from the breeding season, mating is another reason for the prolonged anestrus [172]. The long postpartum anestrus interval in Azikheli buffalo calved in the autumn season might be due to the fact that autumn calvers immediately entered the winter season, which is the coldest of all the seasons in the study area [136] and there is also a fodder shortage as compared to other seasons. Shah et al. (1989) also reported a low frequency of estrus in buffalo during the winter season (November, December, and January) in Swat and attributed it to the fodder shortage during the winter season in the area. However, a nonsignificant effect of season has also been reported in Nili-Ravi buffalo under farm conditions in Pakistan [155, 156] and Egyptian buffalo [173]. In the present study, the percentage of Azikheli buffalo conceived after first service was higher (64.33%), whereas a low percentage of buffalo conceived after first service in buffalo of Bangladesh (50.88%) [147]. Murrah buffalo of India (40%) [144] buffalo in Sri Lanka (45%; Perara and Abeygunawadena, 2000), Nili-Ravi buffalo of Pakistan (47%) [174,175] Egyptian buffalo (55%) [174] and in other various buffalo (56.8%; Barnabe, 1994; 48.3%; Baruselli, 1994; 38.1% to 55.5%; Riveiro et al., 1994). However, the highest percentage of pregnant buffalo to first service was reported in indigenous buffalo of Sri Lanka (77%) [176]. Jainudeen (1986) also reported that the first service conception rate varied from 50% to 75% in water buffalo. According to Shah et al. (1989), the ideal value for the percentage of buffalo conceived after first services is 50%. In the present study, the observed percentage of pregnant buffalo after first services is 64.33 % which is above the ideal value. It was observed in the present study that Azikheli buffalo conception after second service was 24.47 %. Alam and Ghosh (1993) also reported 24.56% of Bangladeshi buffalo conceived after availing of a second service. Azikheli buffalo conceived after availing of third (5.36%) and fourth and more than fourth services (5.83%) were lower than reported for Bangaldshi buffalo, which were 12.28% for third and 12.28% for fourth service [147]. Calving interval is one of the most important parameters to evaluate the productive and reproductive efficiency, economic value, and number of calves by lifetime in a farm and/or in a population [105,106,177]. An ideal calving interval is considered to be 12 to 14 months, whereas a longer or shorter calving interval than the ideal is unprofitable [104]. The overall mean calving interval observed in Azikheli buffalo in this study was 489.16±5.82 days. A close value of calving interval to the present study has been reported in Murrah buffalo (481±13 days) [178] (492 days) [179]. Nepali buffalo (486 days) [180] and Marathwada buffalo (496.251±5.94 days) [181]. However, a shorter calving interval than the present study was reported in Nili-Ravi buffalo of Pakistan (420 days) [182]. Anatolian buffalo in Turkey (441.97±7.93 days) [120]. Surti buffalo in India (461.68±8.429 days) [183], crossbred of Jafarabadi, Murrah, and Mediterranean buffalo in Brazil (409±105 days) [184], Romanian buffalo (437 days; Paraschivescu et al., 2007), Murrah, Mediterranean, and Carabao buffalo of Brazil (446.7±10.4 days) [185] and buffalo in Venezuela (473.9±3.0 days) [107]. Longer calving interval than the present study was also reported in Nili-Ravi buffalo in Pakistan (522.72±2.66 days; 517.29 days; 508.06±2.76 days) [156,174,186]. Murrah buffalo in India (560±38.85 days; Narasimharao and Sreemannarayana, 1994), Bhadawari buffalo (524 days) [187]. Nagpuri buffalo (510 days; Shrikhande et al., 1998), Swamp buffalo in Indonesia (540-630 days) [188] Azerbaijan buffalo in Iran (510±30 days) [189] and Bangladeshi buffalo (544.04±17.57 days) [147]. In this study, a highly significant (P = 0.004) reduction in mean calving interval was noted as the parity number advanced from first to fourth. A significant effect of parity on calving intervals was also reported in Nili-Ravi buffalo, where the first and second calving intervals were significantly longer as compared to the calving intervals in later parities [156] Shah et al. (1989) reported that the calving interval is significantly shorter in the higher parity than in the first parity. Lundstrom et al. (1982) also reported that the calving interval was significantly longer between the first and second calvings than subsequently. In Surti buffalo, the effect of parity reported was significant, with a longer calving interval in first parity than later parity [183]. The long calving interval in Azikheli buffalo in first parity compared to other parities might be due to the lactation stress and longer open period required by buffalo, which have still not reached mature size [178]. The selection of buffalo with better reproductive efficiency might be another reason for the short calving interval in Azikheli buffalo, as Usmani and Mirza (2000) believed farmer selection or retaining of the buffalo with better reproductive efficiency could be a reason for the short calving interval in subsequent parities as compared to the first parity. However, in Mehsana buffalo, Siddique et al. (1984) reported a non-significant effect of parity on calving interval. A non-significant effect of season on calving interval was observed in this study. Similar results regarding the effect of season on calving interval have also been reported in Nili-Ravi buffalo [157], Murrah buffalo [111,112] and Egyptian buffalo [190]. However, the season of calving was reported to significantly affect the calving interval in Nili-Ravi [156,186,163]. Murrah buffalo [191,185], Surti buffalo [183], Anatolian buffalo [120], and buffalo in Venezuela [107,192]. The dry period is one of the important factors that influence lifetime milk production and has been established as a necessary management practice to maintain profitable milk production in dairy animals [117]. In dairy buffalo, the dry period has a marked influence on the cost of milk production and replacement rate [112]. The mean dry period observed in this study was 119.47 ± 2.58 days. A comparable dry period of 115±15 days has been reported in Azerbaijan buffalo [189]. Longer dry period than the present investigation has been reported in Nili-Ravi buffalo (216.07±16.62 days) [193] 131 days [194] Kundi buffalo (335 days) [195], Murrah buffalo (144±26 days) [194] 174.06±9.50 days; [121], Pandharpuri buffalo (140.00±10.57 days) [196] 189.54±2.09 days) [197] Kalahandi buffalo (218.59±3.97 days) [128]. Marathawada buffalo (174.17±5.77 days) [181] and Chilika buffalo (192±20 days) [198]. In this study, a significant effect of parity was noted on the dry period, with a highly significant reduction in the mean dry period as parity increased (P=0.03). A significant effect of parity on dry period was also reported by Kanaujia et al. (1975) in Indian buffalo: dry period was longest in first parity and there was a significant reduction in dry period in later parities. In Surti buffalo, Bharat et al. (2004) observed that the dry period was longer in early parity, reduced significantly up to fifth parity, and increased again in later parities. Variation in dry period could be attributed to the yielding capability of the buffalo; in higher-yielding buffalo, the dry period will be shorter [199]. As the first parity buffalo seems to have poor lactation yield, the dry period may be longer as compared to the second and later parities. An increased dry period causes an increased calving interval, which in turn reduces the calf crops. Optimizing the dry period to 45-60 days depends on reproductive management [200]. Selection, feeding schedule, and managemental practices favor the trait of a short dry period in buffalo [121]. However, Das et al. (2005) reported a non-significant effect of parity on the dry period in Swamp buffalo. No significant effect of season on the dry period was observed in this study (P > 0.05). A non-significant effect of the calving season on the dry period was also reported in Nili-Ravi buffalo in Pakistan [125]. However, a significant effect of the calving season was reported on the dry period in Murrah buffalo [156]. To exploit the production potential of any species of domestic animals, basic information regarding different reproductive parameters such as ovarian activity, cornual implantation, and sex ratio is of prime importance [126]. Several attempts have been made to increase the frequency of a desirable sex in animals without much success. If the frequency of a desirable sex is increased, then genetic gain can be maximized through increased intensity of selection [201]. The overall calf-sex ratio observed in Azikheli buffalo in this study was 100 : 89
. Male to female calf ratio has been reported as 52.28:47.55 in Nili-Ravi buffalo (Malik and Ahmad, 1969), 48.3:51.7 [202], and 50:50 [129] in Murrah buffalo. In this study, a non-significant (P > 0.05) effect of parity on the calf-sex ratio was observed. Similar results were also reported by Rao and Rao (1996a) and Jogi et al. (1998). In the present study, there was a highly significant (P = 0.045) increase in male births in the autumn compared to the spring season. However, a non-significant influence of season on sex ratio has been reported in Murrah buffalo [129,202]. No extrinsic factors (month, season, year of calving, and lactation number) either during the prenatal or postnatal life of an animal were found to influence the sex ratio [203-207] and sex determination is controlled by genetic factors only [129]. However, certain sires produced a higher number of female calves. Hence, by selecting certain sires, a greater number of females can be obtained [208,209]. Similar findings have been reported by Mishra et al [210]. Pander et al [211] in goats, and Jogi and Johar in pigs [212,213].
Conclusion
The present study evaluated the management effect of social groups and topographic conditions on key reproductive traits. The Azikheli buffalo is kept in its home tract by different social groups (landowners, Gujars, and tenants) under different topographic conditions (hill slopes, undulating areas, and valley bottoms). They are currently caring more for the breed as they are primarily dependent on the sale of livestock and livestock products for their livelihood. A total of 3140 data records of various performance traits were collected, representing the pubertal age, postpartum estrus interval, percentage of pregnant buffalo cows, calving interval, and dry period afore mentioned and analyzed.
The earlier puberty age at the valley bottom and undulating zone and a short postpartum anestrus interval at the undulating zone provide scope for improvement through genetic selection and better feeding in other ecological zones as well. The higher first service conception rate and a smaller number of services per conception in comparison to other buffalo breeds. Suggest it to be a specific genotype trait of Azikheli buffaloes and indicate good adaptability of the Azikheli buffaloes to different ecological zones in the study area. The comparatively better reproductive performance of the Azikheli buffalo makes the Azikheli an important genetic resource in mountain environments and therefore warrants conservation of its key reproductive traits through appropriate breeding programs. In the current study, traditional measures of fertility like postpartum anoestrus interval, conception efficiency, and calving interval have been investigated. Physiological parameters of fertility, such as the commencement of luteal activity postpartum, ovulation time, lifespan of the corpus luteum, pattern of estrus cyclicity, and maintenance of pregnancy, assessed by milk progesterone levels, are necessary to be investigated to obtain information on the inherent capability of the Azikheli buffalo cow to resume ovarian cyclicity postpartum, which is useful for selecting buffalo for improved fertility. There is a need to investigate the causes of late pubertal age, the long postpartum anoestrus interval, the long calving interval, and the long dry period and devise strategies to optimize these reproductive performances.
Conflict of Interest
The authors declare that there are not any potential conflicts of interest regarding the publication of this paper.
Data Availability
The data used to support the findings of this study are included within the article.
Acknowledgements
The authors are thankful to anonymous reviewers for their valuable comments, suggestions, and critical reading of the manuscript. I am also very appreciative of the co-authors for their critical and technical improvements to our manuscript. I express my sincere thanks to our Research Team/Group for their kind collaboration and assistance. Special thanks to Professor Dr. Samina Jalali for their supervision and guidance.
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