Heterosis and Reciprocal Effect For Body Weight and Leather Properties in Hybrid Goats

Identification and evaluation of economically important traits in livestock is central to genetic improvement. The objective of this study was to evaluate heterosis and reciprocal effects for bodyweight and leather properties among progenies of pure and reciprocal crossing of West African Dwarf (WAD) and Red Sokoto (RS) goats. Bodyweights of 96 kids were recorded at birth, weaning and yearling. Skins collected from slaughtered goats at yearling were processed to leather using vegetable tanning approach. The leathers were subjected to physical analysis to determine Thickness, Percentage Elongation (PE), Surface Area, weight and grain properties comprising Load at Crack, Load at Tear, Distension at Crack and Distension at Tear.  Heterotic effect for bodyweight was negative at birth (-8.99%) and weaning (-11.15%) but positive at yearling (6.64%). Specific heterosis for bodyweight at yearling was higher for progenies of WAD does serviced with RS bucks. General and specific heterosis were positive for all the leather traits except PE. Specific heterosis was higher when RS does were serviced with WAD bucks. Reciprocal effects for bodyweight reduces with increase in goats’ age (Birth Weaning Yearling: 9.88 6.28 5.62).Reciprocal effects for grain properties were generally higher than other leather traits. This study concluded that WAD and RS goats are dissimilar in leather traits and bodyweight at different ages, and that choice of sire or dam for successful crossbreeding programme is trait dependen

Repeatability Estimates for Body Weight, Skin and Leather Properties in Pure and Reciprocal Crosses of Nigerian Goats

This study evaluated repeatability estimates for body weight, skin and leather properties using progenies of pure and reciprocal crossing of West African Dwarf (WAD) and Red Sokoto (RS) goats. The progenies were labelled as RSxRS, WADxWAD, WADxRS and RSxWAD. Data on bodyweights of the progenies were taken at birth, weaning and at yearling when the males were slaughtered to obtain skins which were tanned to leather. Data on physical properties of the skin and the leathers were also taken. The result revealed a low range repeatability estimate for birth weight (0.01 – 0.23) and yearling weight 0.05 – 0.20, while weaning weight ranged from low – high (0.05 – 0.51). Repeatability estimates for leather properties generally ranged from low to moderate among the goat genotypes except for thickness (0.41) and surface area (0.64) of WADxWAD, and distention at crack (0.47) of RSxWAD. The results revealed that genotype is of variable influence on the repeatability estimate of bodyweight, skin and leather traits in the goats. It is therefore concluded that long term breeding of Nigerian goats would result in more consistent body weights, skin and leather properties.Keywords: Breed, Bodyweight, Leather, Reciprocal crossin

Fertility, hatchability and growth performance of native and crossbred chickens in a tropical climate

Fertility and hatchability serve as measures of genetic and reproductive fitness of individual bird. These two along with growth performance are important yardsticks in evaluating the economic efficiency of parent stocks. There is no previous study on the evaluation of Goliath and Sussex chickens for hatchability, growth and crossbreeding potentials in Nigeria. The present study was conducted to evaluate fertility, hatchability and early growth performance of Yoruba ecotype, Marshall, Sussex, Goliath and their crossbred chickens in Nigeria. A total of 895 eggs were used to evaluate fertility and hatchability of eggs. 583 chicks were used to evaluate early growth performance in the 10 genetic groups. Mean %Fertility of egg, %Hatchability of egg set and %Hatchability of fertile eggs were 74.44%, 61.50% and 82.09%, respectively. Crossbreeding (reciprocal) between Yoruba ecotype and either Marshall or Goliath chicken gave better fertility and hatchability than the cross between Yoruba ecotype and Sussex chicken. Reciprocal effects on fertility and hatchability and liveability generally favour the use of Yoruba ecotype cocks on exotic hens. Marshall chicks were significantly higher (p<0.05) in weekly body weights than all the other nine genotypes from the 5th to the 8th week of age. Crossbred chicks produced by Marshall cocks and Yoruba ecotype hens were significantly higher (p<0.05) in weekly body weights than other crossbred chicks from the 5th to the 8th week of age. Male chicks were significantly higher (p<0.05) in weekly body weights than female chicks. Interaction between genotypes and sex was significant (p<0.05) on the weekly body weights. It was concluded that the highest genetic gain in body weight and Feed efficiency through crossbreeding would be achieved by crossing Marshall cocks with local Yoruba ecotype hens. However, higher fertility and hatchability of eggs and survivability of chicks may be achieved by mating Yoruba ecotype cocks with any of the female exotic hens.Key words: Crossbreeding, Feed efficiency, Hatchability, Reciprocal effects, Yoruba ecotyp

Effects of genotypes and sex on growth performance of Yoruba ecotype and crossbred grower chickens

Information on adaptability and crossbreeding potentials of exotic birds are important to improve animal protein supply in the tropics. The aim of the present study was to evaluate the performance of exotic grower chicks and their crossbred under a humid tropical environment. A total of 547 chicks which belong to 10 genotypes (Yoruba ecotype, YEC; Sussex, SS; Goliath, GO; Marshall, ML and six crossbred genotypes) were evaluated for growth performance from 8 to 20 weeks of age. Marshall grower chicks were significantly higher (p<0.05) in weekly body weights than, Yoruba ecotype, Sussex and Goliath, and the six crossbred genotypes throughout the 12 weeks study. Crossbred chicks that were produced from Marshall cocks and Yoruba ecotype hens were significantly heavier (p<0.05) in weekly body weights than SS x SS, Go x GO and other crossbred chicks. Male chicks were significantly higher (p<0.05) in weekly body weights than female chicks from 9 to 20 weeks of age. There were significant (p<0.05) interaction between genotype and sex on body weights of crossbred chicks. Reciprocal effect was significant (p<0.05) on body weight of chicks in all the crossbred groups. Reciprocal effect favoured chicks that were born to purebred cocks and Yoruba ecotype hens. The study therefore recommends the use of Marshall cocks and Yoruba ecotype hens to improve poultry meat production in Nigeria.Key words: Body weight, Crossbred chicks, Genotype, Interaction, Reciprocal effect, Tropical climat

Somatic Cell and Cheesemaking Variables of WAD Goat Milk: Influence of Parity and Lactation Stage

The suitability of any goat breed for dairy purposes depends on its assessment of milk-related traits. This study evaluates the influence of parity and lactation stage on somatic cell count (SCC) and cheese-making variables of West African Dwarf (WAD) goat milk. A total of 48 lactating WAD does of three different parities (the 1st, 2nd, and 3rd) were milked over a period of time-phased into three stages of lactation (early, mid, and late). The milk was subjected to SCC and cheese-making during which coagulation time, cheese yield (CY), whey volume, and whey pH were recorded. Collected data were subjected to analysis of variance and Pearsons’ correlation. The result revealed that the milk SCC of the does in the 3rd parity (2.16 x 105 cells) was significantly (p<0.05) higher than 1.89 x 105 and 1.87 x 105 cells in the milk of the 1st and the 2nd parity does respectively. There was a similar variation trend of SCC as lactation progresses in each of the parities. The CY significantly increased (p<0.05) as lactation progresses in the 1st parity (early – 16.95%; mid – 17.21%; late – 20.85%) while, the milk of the 2nd and the 3rd parity from mid to late lactation stage yielded statistically similar cheese that was comparable with late lactation CY of the 1st parity does. The lactation stage and SCC were positively correlated with CY. The volume and pH of the whey were neither affected by the lactation stage nor parity. The study concludes that parity uncovers the effect of lactation stage on the milk SCC of WAD does while the milk obtained from mid to late lactation stage yields more cheese