Reproductive performance of goats in Eastern and North-eastern India

S Zeshmarani, K C Dhara*, A K Samanta, R Samanta and S C Majumder

Department Of Animal Production and Management, WestBengal Universityof Animal and Fishery Sciences, 37, Belgachia Road,
Kolkata - 700 037, India
* AICRP(G), Department of APM, WBUAFS, Kolkata-700037, India
jesmaraniapm@rediffmail.com

Abstract

Present study was conducted on 45 Black Bengal and 43 Assam Hills goats of the college of Agriculture, Central Agricultural University farm, Iroisembam, Imphal and 30 Manipuri non descript around Imphal with similar age group. During the experiment the numbers of male animals were reduced by culling and castration. All female goats were of first parity.

The Black Bengal attained age at puberty, age at conception and age at first kidding earliest followed by Assam Hills and Manipuri non descript goats (P<0.05). Winter born kids are more efficient for Assam Hills and Manipuri non descript, whereas in Black Bengal it was monsoon born kids. In all the three groups, single born kids have shortest period for the reproduction characters. Black Bengal was found to be superior in all the reproductive characters indicating efficient reproduction in this breed than Assam Hills and Manipuri non descript.

Key word: Assam hills, Black Bengal, India, Manipuri non descript, reproductive performance

Introduction

Goat is one of the earliest discoveries of mankind in prehistoric times as ready and easy source of meat and gain importance mainly on account of their short generation interval and higher rate of prolificacy. Eastern and north eastern part of India is proud of prevailing very good quality goat breeds like Black Bengal, Assam hills, Ganjam etc. Black Bengal is a famous breed known for high prolificacy, superior chevon quality, best quality skin, early sexual maturity, low kidding interval and very good adaptability. The home tract of the breed is throughout West Bengal although it is distributed in the adjoining part of Jharkhand, Orrisa, Bihar, Tripura states of India and also available in Bangladesh. Assam Hill Goat breed is found in Assam and its adjoining areas. The body coat is black and sometimes white and the breed is famous for meat production. It is a poor milk yielder. This breed was utilized by the poor farmers of Assam and its adjoining areas for their economic upliftment. Local non-descriptive goats at Imphal, Manipur is also preferred by the rural farmers at this area as there livelihood. The present study was made with the objective to determine the reproductive performance of Black Bengal, Assam Hills breeds along with local non-descriptive goats at Imphal, Manipur, India for ascertaining the most efficient breed in relation reproductive performances for economic goat keeping in this agro climatic condition.

Materials and methods

Experimental period

The research work was conducted for a period of two years and two months from December 2002 to January 2005. Each year was divided into three seasons according to the climatic period of the areas: summer (March to June), monsoon (July to October) and winter (November to February).

Site of experiment and experimental animals

Agro-climatic condition

The goat farm was located at 23'83º N to 25'68 º N latitude and 93.03 º E to 94.78 º E longitude. Altitude of Imphal above sea level is 790m with minimum temperature of 2.0 º C and maximum temperature 38.0 C. Average rainfall of the area is 1467.5mm.

Managemental practices

The experimental animals were kept in semi-intensive condition throughout the period of study. The animals were allowed to graze from 9.00 am to 4.00 pm. Concentrates were given in the morning at 8.00 am. The kids were allowed to run with their dams. Weaning was done at 3 months of age. Ad libitum drinking water was made available in all times. Routine deworming was done on the basis of faecal examination. All the animals were vaccinated against Peste des Petits Ruminants, goat pox, Foot and Mouth Disease, enterotoxaemia.

Reproductive traits

The age at puberty, age at conception, age at first kidding and gestation period were estimated as per Ahamed (1992).

Statistical analysis

The effect of the different breeds, seasons and litter size on the variability of different important reproductive traits was estimated by analysis of variance. The formulae used for statistical analysis were:

Y_ijkl = μ+Ai +Bj + C_k+e_ijkl

Where:

Y_ijkl= l^th animal of the i^th breed under j^th season of k^th littersize

μ = overall mean,
Ai = Effect of Breed (i = 1 to 3),
Bj = Effect of Season (j = 1 to 3)

C_k = Effect of Litter size (k = 1 to 3) and
e_ijkl = Random error on observation distributed NID (0, σ2e)

From the above model, it was calculated

CF = (GT) ²/N
SS_A (Between breeds) = ∑ Ai² - CF
SS_B (Between seasons) = ∑ Bj² - CF

SS_C (Between litter size) = ∑ Ck² - CF
SS_T (Total) = ∑ Yijkl² - CF

SSe (error) = SS_T - SS_A - SS_B -SS_C

The critical difference test (CD test) was carried out for the traits, which showed significant differences. This is done to compare between the means of sub-classes by applying the following formula.

| B₁- B₂ | > t_1/2α(N-5) X √MSe (1/N₁ + 1/N₂)

Result and discussion

Effect of genetic group

Black Bengal goat has the shortest age at puberty, age at first conception, age at first kidding and gestation period in comparison to Assam Hills and Manipuri non-descriptive goats (Table 1).

Table1. Mean ± SE (describe) of the reproductive traits of Black Bengal, Assam Hills and Manipuri non descript
Reproductive traits, days	Black Bengal (45)	Assam Hills (43)	Manipuri non descript (30)
Age at Puberty	190 ±1.89^c	264 ± 1.68^b	317 ±1.7^a
Age at Conception	220±2.43^c	291± 1.92^b	344±2.27^a
Age at first kidding	366±2.41^c	441±2.28^b	496±2.43^a
Gestation Period	145±0.41^c	148±0.37^b	152±0.49^a
^a,b,c Values bearing same superscript between columns do not differ significantly (P<0.05)

The effect of genetic group on those reproductive traits were highly significant (p<0.01). The literature comprising these three genetic groups was not available, however the reproductive performance of Black Bengal goat has been corroborated with other workers and it was found that result regarding age at puberty and age at first kidding was in agreement with Mayenuddin and Waheb (1989) and Ahamed (1992) while age at first conception and gestation period was similar to the finding of Mia et al. (1996). A higher value for age at conception and age at first kidding than the present findings were observed by Nahendeka et al (1995). Das and Goswami (1992) reported a lower length for gestation period in Assam Hills breed.

Effect of season

In all the three breeds, significant (p<0.01) seasonal variation was observed in age at puberty, age at first conception and age at first kidding, while in case of gestation period seasonal variation was found to be non-significant (P>0.05). Winter borne kids of Assam Hills and Manipur non-descriptive breeds were more efficient regarding reproductive performance while in case of Black Bengal breed monsoon borne kids were more efficient (Table 2).

Table 2. LSM ± SE of reproductive traits of Black Bengal, Assam Hill and Manipuri non descript in different seasons.
Reproductive traits	Summer			Monsoon			Winter
Reproductive traits	Black Bengal (11)	Assam Hill (12)	Manipuri non descript (8)	Black Bengal (15)	Assam Hill (13)	Manipuri non descript (9)	Black Bengal (19)	Assam Hill (18)	Manipuri non descript (11)
Age at puberty, days	198±3.28^a	274±2.7^a	320±2.82^a	186±3.51^b	266±2.92^a	320±2.95^a	188±2.98^b	253±3.1^b	309±3.04^b
Age at Conception, days	229±4.22^a	298±3.08^a	345±3.77^a	215±4.52^b	292±3.34^a	350±3.95^ab	216±3.84^b	283±3.54^b	337±4.06^b
Age at 1^st Kidding, days	375±4.19^a	448± 3.67^a	498±4.04^a	360±4.49^b	444±3.7^a	502±4.22^ab	362±3.81^b	432±4.21^b	487±4.35^b
Gestation period, days	145±0.71^a	148± 0.59^a	153±0.82^a	145±0.76^a	147±0.64^a	152±0.86^ab	146±0.64^a	148±0.68^a	150±8.84^b
Values bearing same superscript between columns do not differ significantly (P<0.05).

Same to the present findings, significant effect of season on reproductive character was observed by Kumar et al (1980) and Singh and Singh (1999) in Black Bengal goat.

Effect of litter size

Significant (p<0.01) variation among different litter size was observed in age at puberty, age at first conception and age at first kidding while in case of gestation period the variation was found to be non-significant. It is evident that age at puberty, age at conception and age at first kidding were earliest in single born goats in all the three genetic groups. The reproductive cycle was most delayed in triplets and twin born goats were intermediated (Table 3).

Table 3. LSM ± SE of reproductive traits of Black Bengal, Assam Hill, and Manipuri non descript in different season in different type of birth.
Reproductive traits	Single			Twin			Triplet
Reproductive traits	Black Bengal (12)	Assam Hill (17)	Manipuri non descript (16)	Black Bengal (24)	Assam Hill (20)	Manipuri non descript (8)	Black Bengal (9)	Assam Hill (6)	Manipuri non descript (6)
Age at puberty, days	174 ±3.29^c	259±2.5^b	309±2.35^b	190±2.25^b	265±2.4^a	317±2.11^a	207±4.02^a	269±3.66^a	324±3.99^a
Age at Conception, days	210±4.23^b	288±2.86^b	334±3.14^b	220±2.90^ab	290±2.75^a	346±2.82^a	229±5.17^a	295±4.18^a	351±5.34^ab
Age at 1^st Kidding, days	355±4.20^a	437±3.40^b	486±3.36^a	366±2.87^ab	440±3.27^a	498±3.02^a	375±5.13^a	446±4.97^a	504±5.71^a
Gestation period, days	144±710^b	147±0.55^a	151±0.68^a	145±0.49^a	148±0.53^a	151±0.61^a	147±0.87^a	149±0.8^a	153±1.16^a
Values bearing same superscript between columns do not differ significantly (P<0. 0.05).

Conclusion

It is concluded from the present study that Black Bengal goat is best choice breed in relation to reproductive performance under this agro climatic condition for economic goat keeping.

References

Ahamed J 1992 Reproductive pattern of Black Bengal, Recent advances in Goat Production in Goat Production. Proceedings of the 5^th International Conference on goats, New Delhi P 1215 - 1220

DasD and Goswami R N 1992 recent advances in goat production proceedings of papers presented at V International Conference on goats, New Delhi, India, March, pp 519-525

Kumar A, Bight G S and Siddu N S 1980 Age at first kidding of indigenous exotic and crossbreed goats. Indian Journal of Dairy Sciences 33(2): 207 -208

Mia M M, Ali A and Bhuijan A K F H 1996 The reproductive performance of Black Bengal, Barbari, Barbari x Black Bengal and Anglo Nubian goats. Indian Veterinary Journal 73 (10):1048 -1052

Mayenuddin M and Wahab M A 1989 Reproductive performances of Black Bengal goats in Manikganj. Bangladesh Veterinarian6(1): 48-49

Nahardeka N, Das A, Goswami R N, Roy T C and Gogi P K 1995 Reproduction performance of Assam Hills goats and their cross breeds with Bengal. Indian Journal of small ruminants 1: 8-14.

Singh D K and Singh N K 1999 Genetic Breeding on reproductive performance of Black Bengal and its half breeds with Beetal under farm condition. Indian Veterinary Medical Journal 23: 97-100