Oestrus patterns of progesterone-treated Yankasa ewes in the hot dry and late wet seasons

Differences in oestrus patterns of 20 Yankasa ewes of 2 age groups (Adult vs Yearling) in hot dry and late wet seasons were investigated in a 2 X 2 X 10 factorial experiment. Mean oestrus cycle length was significantly (p0.05). Season significantly affected the frequency of oestrus, while age group did not. No behavioural oestrus were observed for 60 and 0% of the ewes in the hot dry and late wet seasons, whereas 25, 15 and 0% of the ewes in the hot dry and 5, 10 and 85% of the ewes in the cold dry season came on heat once, twice and thrice respectively, within a period of 40 days. The observed disruptions in the oestrus cycle of the ewes in the hot dry season confirm the heat stress effect on the reproductive behaviour of ewes

Genetic and environmental factors affecting weaning weight in rabbits

A total of 139 kid records collected over a 9-month period was analysed to evaluate the effects of parity, breed, litter size born alive (LsizeA), sex and season on the weaning weight of rabbits. Parity, breed and sex had no effect on weaning weight. However, litter size born alive and season significantly (P<0.01) affected weaning weight. Kids born to Chinchilla does were heavier (525.9 g) than those born to New Zealand White (500.5 g) and California (490 g) does. There was no particular trend on the effect of litter size born alive on weaning weight. However, litters in LsizeA of 2 (523.2 g) and four (572 g) were superior to the other litter sizes, while kids in LsizeA of 5 were the lowest (463 g). Kids born during the late wet season (627 g) were also superior to those born during the early wet season (451 g) and late dry season (439 g) (P<0.01)

Environmental factors affecting litter size and gestation length of three breeds of rabbits

Data consisting of 303 records on three different breeds of rabbits ((New Zealand White (NZW), Californian White (CW) and Chinchilla (CH)) were subjected to least squares analysis to ascertain the effects of breed, parity, season and year of breeding on gestation length (GL), litter size at parturition (LSP), alive (LSA) and at weaning (LSW). Least squares means ± SE for GL, LSP, LSA, LSW were 32.4 ± 0.32, 4.7 ± 0.19, 3.7 ± 0.16 respectively. GL was significantly (P<0.01) affected by breed, parity, season and year of breeding, while LSP and LSW were significantly (P<0.01) affected by breed, parity, season and year of breeding. LSA was however, affected by parity and season of breeding only (P<0.001)

Appropriate breeding strategies for small ruminant production in West and Central Africa

Small ruminant production is widespread throughout all the ecological zones of West and Central Africa. The seasonal climate of the area influences growth and reproduction of the animals through its effects on forage availability and disease prevalence. Distribution of the breeds show evidence of ecological adaptation, the dwarf, trypanotolerant breeds being predominant in the humid areas while the larger, long-Iegged breeds predominate in the drier areas. There exist at least 11 sheep and 4 goat breeds indigenous to the regions but many are still poorly characterized. There is a great need for the standardization of breed names across national boundaries. Large gaps still exist in the available performance data for most of the breeds. Generally however, their reproductive rates are fairly high while growth rates and milk yields are low. Genetic improvement should be focussed on growth and reproductive traits. I for breed improvement on a national or regional scale, an open nucleus breeding scheme is recommended, involving central nucleus, multiplier and farmers flocks. Such a scheme should be backed by an effective extension service for maximum effect

Evaluation of Udder traits in West African Dwarf Goats

Udder traits of West African Dwarf (WAD) goats and factors influencing them were studied using 185 does located in South Western Nigeria. Traits evaluated were udder length (UL), udder width (UW), udder circumference (UC) and udder volume (UV). Others were teat length (TL), teat width (TW), teat circumference (TC), distance between teats(DT) and height of teat from the ground (HTG). Udder length was significantly (

Semen quality of Yankasa rams

Presents results of a study carried out to determine the ejaculate characteristics of Yankasa rams in Nigeria. Three rams of proven fertility from the breeding herd at shika, of average age of 29 months were investigated. Ejaculates collected during the wet season had higher volume, pH, sperm motility and percentage of normal sperms than those collected in the dry season. Differences between rams were insignificant for all traits except ejaculate volume and sperm motility. The average sperm output per ejaculate was 2.558 x 109 spermatozoa, sufficient to inseminate between 5 and 20 ewes depending on condition of storage. Yankasa rams produced semen which compared favourably in terms of total sperm output per ejaculate and qualitative traits to values for semen of better known temperate breeds of sheep. The observed differences did not appear severe enough as to prevent all year round breeding

Effects of method and length of storage on egg quality of giant african land snail (a. Marginata)

Seventy five giant African land snails were used to investigate the effect of method and length of storage on snail egg quality. Snail eggs were stored either in fridge (cold), in a container on a shelf (ambient) or in earthen pot (earthen) for 1, 2 3 and 4 weeks. Parameters measured were: external (egg length, egg weight, egg circum- ference, egg shape index, percentage egg weight loss, percentage egg volume loss) and internal (albumen weight, albumen height and egg pH). Storage method had no effect on external egg parameters measured but affected internal parameters (p<0.001). Length of storage had significant effect (p<0.01) on albumen height, and weight and volume percentage losses (internal parameters). Egg weight loss was highest in earthen pot and lowest in both cold and ambient for the first two weeks of storage, thereafter, it increases with length of storage. Egg volume loss was also found to be highest in earthen pot and lowest in cold storage. It can be concluded that room and cold storage can be used for snail egg (Archachatina marginata) between 1-2 weeks of storage for better egg quality.Setenta y cinco caracoles gigantes africanos fueron empleados para investigar el efecto del método y duración del almacenamiento sobre la calidad de sus huevos. Los métodos de almace- naje fueron: refrigerador (cold), contenedor en una estantería (ambient) y olla de barro (earthen) durante 1, 2, 3 y 4 semanas. Se midieron carac- terísticas externas (longitud, peso, circunferen- cia, forma y pérdidas de peso y volumen) e internas (peso y altura del albumen y pH del huevo). El método de almacenamiento no tuvo efecto sobre las características externas, pero afectó a las internas (p<0,001). La duración del almacenamiento influyó (p<0,01) sobre altura del albumen, y pérdida de peso y volumen. La mayor pérdida de peso del huevo durante las dos prime- ras semanas de almacenamiento se registró en la olla de barro y aumentó con la duración del alma- cenamiento. La pérdida de volumen también fue mayor en la olla de barro y menor en el almacena- miento en frío. Se concluye, que el almacenamien- to en frío o a temperatura ambiente de los huevos de (Archachatina marginata) durante 1-2 sema- nas permite mejor calidad

Effect of environmental changes on some physiological parameters in the Yankasa ewe

Three experiments were conducted to determine the effects of heat stress oil pulse rate (P), respiratory rate (R), rectal temperature (I} and sweating rate (S) with respect to pregnancy, coat type, pigmentation and dium.al variation, and also the heat stress of the animal in each group. Non-pregnant ewes had lower P (90.7 vs 103.5 beats/min) and higher H (0.76 vs 0.65) (P<0.001) than the pregnant ewes. However, the effects of pregnancy on R and t were insignificant (P>0.05). Sheep with smooth, curly and intermediate coat types differed significantly (P<0.01) in P (75.0 vs 80.1 vs 82.5 beats/min, respectively). Effect of coat on R, T and H were insignificant (P>0.05). Non-pigmented ewes had significantly higher (P<0.05), T (39.1 vs 38.9"C) and H (1.37 vs 1.30) than pigmented ones. However, the former had lower (P<0.01) sweating rate (13.5 vs 15.9 min) and sweat gland density than the latter, but P and R were not significantly affected by the pigmentation level of the animals. Time of sampling significantly affected (P<0.001) most of them