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| Articles
by
U. Herbert |
Total Records (
3 ) for
U. Herbert |
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I.P. Ogbuewu
,
U.E. Ogundu
,
M.N. Opara
,
I.C. Okoli
,
D.O. Umesiobi
,
U. Herbert
and
M.U. Iloeje
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The application of technologies in the field of male reproductive physiology has advanced greatly during past couple of decades. Since, the advent of frozen semen and artificial insemination, reproductive physiologists have attempted to manipulate male reproductive rates of mammals, sometimes successfully or sometimes not. The past five decades has resulted in phenomenal expansion in the improvement spermatozoa with direct application to livestock and medicine. Spermatogenesis had been reported to be induced in male animals using synthetic fertility drugs and local plant extracts. Sperm production and function have been improved via the use of nutritional regiments, semen extender and semen pool admixture. Currently, the sex of animal has been predetermined with 85-95% accuracy by sexing spermatozoa. The current success recorded in male assisted reproductive techniques came about due to advances in computer science, biophysics, cell biology and genetic engineering. This review will briefly cover the developments and modifications of existing sperm manipulation techniques that have direct practical applications today and in the near future in animal agriculture and bio-medicine. |
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Audifax N. Iwu
,
C.S. Ebere
,
I.P. Ogbuewu
,
I.F. Etuk
,
M.N. Opara
,
M.C. Uchegbu
,
I.C. Okoli
,
F.C. Iheukwumere
and
U. Herbert
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Forty eight crossbred male and female rabbits aged 12-14 weeks were used to
study the effects of supplementing Coconut Shell Ash (CSA) on reproductive organ
characteristics and serum sex hormone concentrations of growing rabbits. The
rabbits were divided into 24 males and females, respectively. Each group was
divided into four experimental treatments T1, T2, T3
and T4 of six animals and was further replicated three times with
two animals per replicate in a Completely Randomized Design (CRD). The animals
were fed a commercial grower rabbit ration which was supplemented with CSA at
the rate of 0, 1, 2 and 3 g kg-1 b.wt., respectively. At the end
of 12 weeks feeding, three rabbits were selected from each group, slaughtered
and used to determine reproductive organ characteristics. Blood samples from
the slaughtered animals were collected from the jugular vein and assayed for
serum reproductive hormones concentrations. Data collected were subjected to
analysis of variance. Testicular morphometry result showed that 1 to 2 g kg-1
b.wt. CSA supplementation could improve the weight of testis, size and epididymal
weights indicating that up to 2 g kg-1 b.wt. CSA supplementation
supported superior testicular development. This was associated with increasing
serum testosterone concentration indicating probably a CSA enhancement of metabolic
activity. One gram kg-1 b.wt. was the optimal CSA supplementation
rate in female rabbits, since this led to improved weight of whole reproductive
tract, weight of ovary, oviduct and uterus. This was equally associated with
increased estrogen concentration, which increased with increasing CSA supplementation. |
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U.K. Oke
,
U. Herbert
,
N.M. Anigbogu
and
E.N. Nwachukwu
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Twelve young white Fulani bulls with average live weight of 97kg and age 40 weeks were used to determine rumen metabolites of bovine feed cassava peel in a 3 x 4 factional treatment for a complete randomized design experiment. Three diets containing increasing percentage of cassava peels (0, 20 and 40 percent) in sun-dried form were offered ad-libitum to the experimental animals. Feed intake and body weight changes were measured. Samples of rumen liquor was taken through a rumen tube using a vacuum pump at 0, 0.5, 1.5 and 2.5h after feeding. The pH, total volatile fatty acid, rumen ammonia-nitrogen and osmolality were determined. The average daily intake of total dry matter was highest in diet T2 (20%) on the 10 day of feeding. However treatment had no significant effect (p > 0.05) on mean average daily intake level. When their average daily intake was adjusted to their respective metabolic body weights (Kg BW0.075) those on diet T1 (control) had almost the same value with T2 and T3, respectively. Inclusion level had no significant effect (p > 0.05) on rumen pH, and osmolality. Mean NH3-N was statistically the same (p > 0.05). However correlation coefficient between time and NH3-N was positive in diet T2. (p < 0.05) Concentration of total VFA in rumen fluid increased for all level of cassava peel inclusion and was affected by time after feeding (p < 0.05) with highest value occurring at 1.5h inclusion level of cassava peel. At 40% level of inclusion caused a decrease in rumen NH3-N concentration when sampled at 1.5h. Knowledge of pH and osmolality may benefit the animal through improvement of acid base status. Inclusion of cassava peels in the diet of cattle up to 20% or slightly above 30% is recommended since it gave better NH3-N accumulation in the rumen after ingestion. |
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