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1.
Twenty-one Bunaji (White Fulani, Zebu) and 21 Friesian X Bunaji cross-bred bull calves, approximately 6 months of age, were each divided after weaning into two groups and fed isocaloric rations containing 14.45% (high protein) and 8.51% (low protein) crude protein for 10 months. Serum samples were collected biweekly for 10 months and analysed for serum proteins. Age had no significant effect. The Bunaji had significantly (P less than 0.05) higher total protein, albumin, and alpha 1-globulin than Friesian X Bunaji. While there was no significant difference in body condition score between the two breeds, the Friesian X Bunaji had a significantly (P less than 0.05) higher growth rate. Animals on high protein diets had significantly (P less than 0.05) higher total protein, albumin, alpha 2-globulin, gamma-globulin and total globulin than those on low protein. However, alpha 1-globulin and beta-globulin were not significantly (P greater than 0.05) different for the two treatment groups.  相似文献   
2.
Serum testosterone concentrations and the spermiograms of prepuberal bulls fed two levels of protein diets were investigated at 7, 10, 14 and 18 months of age. Scrotal circumference, body condition score and total sperm counts of those animals on a high protein diet were significantly (P <0.05) higher than those on a low protein diet. However, sperm motility, total dead sperm and abnormal sperm did not differ between the treatment groups (P <0.05). One bull fed a high protein diet had significantly higher testosterone concentrations (basal and peak) than a bull fed low protein throughout the four sampling periods (P <0.05). Testosterone concentrations, scrotal circumference, volume of semen, sperm concentration and sperm output of bulls on low and high protein diets increased significantly with age (P <0.05). Peak testosterone concentrations ranged from 1.1. ng ml−1 at 7 months to a maximum of 5.3 ng ml−1 at 18 months. The 24 h secretory patterns of testosterone were episodic, pulsatile or temporal in nature. The peaks occurred mostly in the morning hours and ranged from one to five in number. Protein intake in prepubertal bulls could have significant influence on spermiogram and testosterone production.  相似文献   
3.
Detailed studies of sperm morphological abnormalities were carried out on 12 Zebu x Friesian crossbred bulls used in a study of the effects of trypanosomosis. Four bulls were infected with T. vivax, another four with T. congolense, while four served as controls. The infected bulls developed chronic trypanosomosis. All the bulls initially had very low sperm morphological abnormalities that were within acceptable limits for fertile animals. After infection there was a rapid and progressive increase in all sperm abnormalities. Spermatozoa of infected bulls were highly deformed with multiple morphological defects. Mean percentage pre-infection baseline values prior to infection for acrosomal, sperm-head, detached heads, proximal cytoplasmic droplets, distal cytoplasmic droplets, sperm-tail, midpiece and total sperm morphological defects ranged between 0.1 +/- 0.1 for acrosomal and 8.3 +/- 3.2 for total morphological abnormalities in the semen of the bulls. All the infected bulls developed sperm morphological abnormalities of more than a mean of 40.0% from the 4th week after infection until the end of the investigation and were considered unfit for breeding. At 7 weeks post-infection (PI) until the end of the study (12 weeks PI), the controls had a mean of less than 5% sperm morphological defects, while the infected bulls had 100%. Mean percentage values of sperm morphological defects throughout the duration of the investigation for control bulls were low and within the normal range for fertile bulls. These values differed significantly (p<0.001) from the elevated values of the infected bulls. The results show that trypanosomosis due to T. vivax or T. congolense infection can render Zebu x Friesian crossbred bulls unfit for breeding within a very short time. The resultant infertility could be of economic importance in trypanosomosis-endemic sub-Saharan Africa where Zebu x Friesian crossbred bulls are kept.  相似文献   
4.
The experiments were performed in order to determine the effect of 8-h road transportation of pigs on erythrocytes osmotic fragility during the hot-dry season, and the ameliorative role of ascorbic acid. Twenty-three adult pigs comprising of both sexes served as subjects for the study. Thirteen pigs administered ascorbic acid (AA) per os 30 min before transportation, at a dose rate of 100 mg/kg served as experimental animals, while ten pigs administered with distilled water per os served as control, and were transported for 8 h during the hot-dry season. EDTA blood samples collected a day before (pre-transportation), immediately after 8-h transportation and 7 days post-transportation were used to determine erythrocyte osmotic fragility. The ambient temperature (AT) and relative humidity (RH) measured within the vehicle ranged between 30.5 – 39.0°C and 40.0 – 71.0% respectively. These values were outside the thermoneutral zone for the pig, indicating that the season was thermally stressful. Results obtained showed a significant difference (p < 0.05) in percent haemolysis recorded at NaCl concentrations of 0.4% and 0.6% immediately after transportation in experimental pigs and at 0.5, 0.6, 0.8 and 0.9% NaCl concentrations in experimental pigs 7 days post-transportation. In conclusion, result from the present study indicated that 8-h road transportation during the hot-dry season could induce stress resulting in haemolysis of erythrocytes and AA administration ameliorated the stress.  相似文献   
5.
A total of 51 pluriparous post-partum Bunaji (Zebu) cows belonging to agropastoralists were involved in a 2 x 2 factorial experiment for a period of 180 days. The cows were assigned randomly at calving to four treatments: (1) grazing only (no supplementation) and exposure to bull (NSBE); (2) grazing only (no supplementation) and no exposure to bull (NSNE); (3) grazing plus feed supplementation (each cow received 600g of 20.8% crude protein of whole cottonseed supplement per day) and exposure to bull (FSBE); (4) grazing plus feed supplementation and no exposure to bull (FSNE). Cows with an increase in milk progesterone (P(4)) concentration of > or =1 ng/mL from the weekly milk samples were used to analyse the number of days from calving to the time of resumption of ovarian activity. The mean interval from parturition to cyclic ovarian activity for FSBE cows was 95 days, compared to 119 days for the FSNE cows. Intervals to onset of post-partum ovarian activity were 24, 33 and 39 days which were significantly earlier in the FSBE cows, than the FSNE, NSBE and NSNE cows, respectively. Intervals to cyclic activity were 9 and 15 days earlier in FSNE cows than in NSBE and NSNE cows. By 150 days post-partum, 100% and 92% of the cows in the supplemented groups (FSBE and FSNE), had resumed cyclic ovarian activity compared with 75% and 69% for the unsupplemented cows (NSBE and NSNE). It is concluded that nutritional supplementation and exposure to bulls synergistically shortened the length of post-partum anoestrus in zebu cattle. The economic benefits of using exposure to bulls and cottonseed supplementation in this study to enhance early resumption of post-partum ovarian activity of cattle may serve as a management tool in tropical areas where livestock production has some constraints.  相似文献   
6.
A study was conducted to determine the influence of maize stover and cottonseed cake supplementation on age and live weight at onset of puberty in Bunaji heifers. A total of 49 pre-pubertal Bunaji heifers approximately 12 months of age were allotted randomly to one of two treatments of feed supplementation: (i) supplementation with maize stover and (ii) supplementation with cottonseed cake. The heifers were monitored for a period of 18 months for first observable oestrus or onset of puberty. The maize stover group were given maize stover (crop residue) supplementation ad libitum during the dry season; in the cottonseed cake group each heifer received 500 g of cottonseed cake per day during the dry season. The heifers supplemented with cottonseed cake attained puberty at an earlier age (23.9+/-1.2 months) than the heifers supplemented with maize stover (28.2+/-1.3 months; p<0.05). Similarly, heifers on the cottonseed cake supplementation attained puberty at a live weight of 270.5+/-3.5 kg; while the heifers on maize stover attained puberty at 237.6+/-5.8 kg (p <0.05). The cottonseed cake-supplemented heifers had higher daily gains than the maize stover-supplemented heifers. It is concluded that provision of cottonseed cake as a supplement for heifers hastened the onset of puberty when compared to the maize stover supplemented heifers. Puberty can be achieved at an early age with improved nutrition and this can in turn reduce the generation interval and thus increase the rate of genetic gain of indigenous animals. Provision of protein supplements in cattle is recommended, especially in the tropics where marked seasonality of rainfall results in extremely poor pastures and herbage and low available protein.  相似文献   
7.
The aim of the experiment was to evaluate the effect of 4-h load carrying (packing) on donkeys administered with ascorbic acid (AA) during the harmattan season. Six donkeys administered orally with ascorbic acid (200 mg/kg) and subjected to packing served as experimental animals, while six others given only distilled water served as control animals. The rectal temperature (RT) of each donkey and dry-bulb temperature (DBT) and relative humidity (RH) of the research pen were recorded at 0600 hours pre-packing; while post-packing, the values were obtained at 1430, 1600 and 1800 hours. The DBT values (ranges) recorded before, during and after packing were 13.7?±?1.3 °C (11–15 °C), 28.4?±?1.0 °C (22.7–30.3 °C) and 30.6?±?3.0 °C (19.8–45 °C), respectively. The highest temperature–humidity index (THI) of 83.4?±?6.9 was obtained at 1430 hours after packing, and the value decreased to 64.2?±?5.8 at 1800 hours. The thermal environmental conditions were outside the thermoneutral zone for the donkeys. The RT values recorded immediately after packing did not differ (P?>?0.05) in experimental and control donkeys; but at 1600 and 1800 hours, values obtained in control donkeys (38.48?±?0.12 and 38.12?±?0.12 °C, respectively) were significantly higher (P?<?0.05) than those recorded in experimental donkeys (38.16?±?0.14 and 37.85?±?0.14 °C, respectively). In conclusion, administration of ascorbic acid reduced the rise in RT due to packing and may be of value in the amelioration of adverse effects of heat stress associated with work in donkeys.  相似文献   
8.
A total of 137 cycling zebu cows, each receiving a single dose of prostaglandin PGF(2alpha)were used in an oestrus synchronization programme on three different farms. Of the cows on the three farms, 60.6 and 90.5% showed overt oestrus and luteolysis, respectively. Pregnancy rate to fixed time inseminations following single injection of PGF(2alpha)was 61.4% for farm 1, significantly higher than the values of 45.7 and 46.9% for farms 2 and 3, respectively. The pregnancy rates to second service of rebred cows were 53.3, 50.0 and 50.0% for the three farms, respectively, with no significant differences between each.Fertility classification of the cows based on progesterone (P(4)) concentration showed that 6.6% of cows on the three farms were incorrectly diagnosed as having corpora lutea; 2.9% of them had incomplete luteolysis and 5.1% may have lost their embryos between days 21 and 45 post-insemination. The pregnancy rate was 10% higher in the rainy season than in the dry season. Cows with body condition scores of 3 and 4 had a higher overall pregnancy rates than those with a body condition score of 2. The findings of this study further confirm the luteolytic efficacy of prostaglandin in inducing oestrus in zebu cattle and indicate that the nutritional status of the cows must be satisfactory before embarking on oestrus synchronization programmes.  相似文献   
9.
Tropical Animal Health and Production - The aim of the study was to determine some ergonomic parameters of donkeys administered with Pycnogenol® (PYC) and subjected to packing during the...  相似文献   
10.
The study investigated concomitant effect of gestation and high ambient temperature under a tropical environment on rectal temperature (RT), respiratory rate (RR) and heart rate (HR) responses in Yankasa ewes. Twenty Yankasa ewes, consisting of ten pregnant and ten non-pregnant ewes, were used for the study. Ewes were synchronised and bred, such that each gestation phase coincided with different periods of the dry-seasons, early-gestation (cold/harmattan), mid-gestation (peak hot-dry) and late-gestation (late hot-dry). The RT, RR and HR were recorded thrice, 2 days apart at middle of each gestation period at 06:00, 14:00 and 18:00 h, concurrently with dry- (DBT) and wet-bulb temperatures of the experimental pen. The DBT was positively correlated with RT, RR during the different gestation stages. The RT significantly (P < 0.001) increased with the hour of day, regardless of the physiological status of the ewes, with peak at 14:00 h. Values of RT and RR were higher (P < 0.05) in pregnant than non-pregnant ewes at mid- and late-gestation, respectively. Mean RT was lower (P < 0.001) at 06:00 h in pregnant than non-pregnant ewes at early-gestation (cold-dry). The HR was (P < 0.05) higher in pregnant than non-pregnant ewes during the different gestation phases. In conclusion, ambient temperature and gestation concomitantly modulate diurnal thermoregulatory responses of the ewes to hot-dry season. Adequate measures should be adopted to mitigate adverse impact of prolonged high RR on the dam and the foetus during the peak of ambient temperature prevailing in the tropical Savannah environment.  相似文献   
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