Motility and fertilizing capacity of boar semen stored in raffia palm (Raffia hookeri) sap extender at 15°C

Two separate experiments were conducted to test the ability of new semen extenders containing various levels of tropical raffia palm sap in sustaining the motility and fertilizing capacity of boar spermatozoa during storage at 15°C. Highly significant variations (P < 0.01) occurred in the ability of extenders to sustain progressive motility from days 1 to 4 of storage. One of the new extenders, raffia palm extender 2 (RPE–2) was superior to other trial extenders including the control (coconut milk extender, CME) in sustaining progressive motility of boar sperm from 24 - 72 h of storage; average motility scores at 24 and 72 h were 73.0 and 50.0% for RPE-2, 65.0 and 41.0% for CME (control), 55.0 and 36.0% for RPE-1 and 45.0 and 6.5% for RPE-0. Sperm tail vibratory movement was observed in sperm stored in RPE-1 and RPE-0 from day 2 of storage. Sperm in RPE-0 and RPE-1 lost motility completely at 96 h while motility of sperm in RPE-2 showed a sharp drop in motility values from 72 – 96 h relative to control. Average conception rates in 24 gilts inseminated per treatment with semen stored for 24, 48 and 72 h respectively were 83.3, 66.6 and 16.6% for RPE-2, 50, 16.6 and 0.0 percent for RPE-1, 16.6, 0.0 and 0.0% for RPE-0 and 75.0, 50.0 and 26.6% for CME (control). Average number of piglets born using semen stored for 24, 48 and 72 h respectively were 8.0, 8.0 and 6.5 for RPE-2 and 8.2, 8.2 and 6.0 for the control. RPE-2 supported better fetal survival rate than other trial extenders and control. Highly significant variations (P < 0.01) occurred among extenders in conception rate and number of piglets born. These results portray RPE-2 as a reliable short-term liquid semen storage medium for swine artificial insemination in the humid tropics

Morphological characteristics and egg production of forced-moult layers under different moult induction techniques

A study was conducted to investigate the morphological characteristics and egg production of forcedmoult layers. Different feeding patterns designated T1, T2 and T3 representing ad libitum supply of feed and water, no feed but water given ad libitum and no feed or water, respectively, were used to induce moult. T1 served as the control. One hundred and twenty 84-week old layers in their 64 weeks in lay were randomly assigned to each treatment, which was replicated 4 times with 30 hens per replicate.Forced-moult treatments were imposed for 10 days, after which the moulting hens were fed moult diet for 50 days and returned to the same feed as the control. The results of the study revealed that morphological characteristics following moult induction included loss of feathers, dullness of theeyeballs, shriveling and paleness of the comb, wattle and ear lobes. Also the moulting birds emaciated with T2 and T3 losing 18.18 and 25.97%, respectively, of their initial body weights by day 7 of moult induction. The forced-moult groups T2 and T3 stopped egg production by&nbsp; 6 days of moult induction and resumed egg production by day 25. T2 and T3 attained a peak egg production of 71% by the second month following resumption of lay. On the other hand, in the T1 egg production progressively decreased with age

Plasma progesterone profile and ovarian activity of forced-moult layers

Different techniques of moult induction were used to force moult 360 commercial old layers, aged 85 weeks. The techniques were: natural day length with feed and water ad libitum, natural day length with water but no feed, natural day length with no feed and no water, reduced day length with feed and water ad libitum, reduced day length with water but no feed, reduced day length with no feed and no water, designated as T1, T2, T3, T4, T5 and T6, respectively. The T1 served as the control. Sixty hens wererandomly assigned to each treatment which was replicated 3 times. The moult induction period was for 10 days coupled with 50 days of recovery period when the birds were fed low protein moult diet. At day 7, the ovaries of T2, T3, T5, T6 regressed weighing 3.43, 7.03, 5.00, 4.80 g, respectively. These were significantly (P&lt;0.05) lower than the ovarian weights of 34.73 and 35.13 g of T4 and control (T1), respectively. By day 35 of moult induction, the ovaries of T2, T3, T5 showed the greatest recoveryincreasing to 18.53, 20.73, 13.27 g, respectively, while T4 decreased to 13.00 g. The number of large yellow follicles of T2, T3, T5, T6 decreased from 3.33 on day 0 to 0.00 on day 7. By day 21 the large yellow follicles of T2, T3, T5 and T6 started regenerating, ranging between 2.33 and 3.00 and by day 49 were significantly (P&lt;0.05) higher than T4 (1.67). Plasma progesterone levels decreased from between 0.50 and 0.60 ng/ml on day 0 to undetectable levels by days 7 and 14 in T2, T3, T5, T6. By day 21,plasma progesterone levels (ng/ml) started rising in T2 (0.40), T3 (0.33), T5 (0.40), T6 (0.33) although these were significantly (P&lt;0.05) lower than those of T1 (0.77) and T4 (0.81). As the number of large yellow follicles increased, the concentration of progesterone in the plasma increased

Effect of Induced-Moult on the Number Small Ovarian Follicles and Egg Production of Old Layers

Abstract: Influence of induced-moult on small ovarian follicles and egg production of old laying flock was investigated. Small follicles were graded thus: small yellow follicles (SYF), large white follicles (LWF) and small white follicles (SWF). A total of 360 old layers in their 64 weeks in lay were used in a 2x3 factorial arrangement in a Completely Randomized Design (CRD). The induced-moult treatments were natural day length with feed and water ad libitum, natural day length with water but no feed, natural day length with no feed and no water, reduced day length with feed and water ad libitum, reduced day length with water but no feed, reduced day length with no feed and no water, represented as T1, T2, T3, T4, T5 and T6, respectively. Each treatment was replicated 3 times with 20 hens per replicate. At the commencement of the experiment the numbers of the small follicles of the Control (T1) were 7.67 ± 0.88, 18.33 ± 0.88, 2121.67 ± 5.78, for small yellow, large white and small white follicles, respectively. The results showed that with the exception of T4, the numbers of all the small follicles of the rest of the induced-moult groups were significantly decreased (P&lt;0.05) by day 7 of moult induction. The numbers of the small follicles of T2, T3, T5 and T6 gradually increased and became Significantly higher (P&lt;0.05) than the control (T1) by day 49 of moult induction. By day 49, the numbers of the small follicles of the induced-moult hens ranged from 2500± 17.56 to 3670.00± 4.05 (SWF), 24.33±0.88 to 41.00± 0.58 (LWF) and 5.00± 0.58 to 6.67± 0.20 (SYF). The mean egg production of the flock was about 50 % prior to moult induction. The hen-day percent production of the moult groups ranged from 50 to 79 % whereas that of the unmoulted control ranged from 35 to 55 %. In conclusion, moulting initiated regeneration and rejuvenation of follicles. This in turn led to increase in post moult egg production of the induced-moult groups

Subtle genetic changes enhance virulence of methicillin resistant and sensitive Staphylococcus aureus

<p>Abstract</p> <p>Background</p> <p>Community acquired (CA) methicillin-resistant <it>Staphylococcus aureus </it>(MRSA) increasingly causes disease worldwide. USA300 has emerged as the predominant clone causing superficial and invasive infections in children and adults in the USA. Epidemiological studies suggest that USA300 is more virulent than other CA-MRSA. The genetic determinants that render virulence and dominance to USA300 remain unclear.</p> <p>Results</p> <p>We sequenced the genomes of two pediatric USA300 isolates: one CA-MRSA and one CA-methicillin susceptible (MSSA), isolated at Texas Children's Hospital in Houston. DNA sequencing was performed by Sanger dideoxy whole genome shotgun (WGS) and 454 Life Sciences pyrosequencing strategies. The sequence of the USA300 MRSA strain was rigorously annotated. In USA300-MRSA 2658 chromosomal open reading frames were predicted and 3.1 and 27 kilobase (kb) plasmids were identified. USA300-MSSA contained a 20 kb plasmid with some homology to the 27 kb plasmid found in USA300-MRSA. Two regions found in US300-MRSA were absent in USA300-MSSA. One of these carried the arginine deiminase operon that appears to have been acquired from <it>S. epidermidis</it>. The USA300 sequence was aligned with other sequenced <it>S. aureus </it>genomes and regions unique to USA300 MRSA were identified.</p> <p>Conclusion</p> <p>USA300-MRSA is highly similar to other MRSA strains based on whole genome alignments and gene content, indicating that the differences in pathogenesis are due to subtle changes rather than to large-scale acquisition of virulence factor genes. The USA300 Houston isolate differs from another sequenced USA300 strain isolate, derived from a patient in San Francisco, in plasmid content and a number of sequence polymorphisms. Such differences will provide new insights into the evolution of pathogens.</p

A survey of the ATP-binding cassette (ABC) gene superfamily in the salmon louse (Lepeophtheirus salmonis)

Salmon lice,Lepeophtheirus salmonis(Kr&oslash;yer, 1837), are fish ectoparasites causing significant economic damage in the mariculture of Atlantic salmon,Salmo salarLinnaeus, 1758. The control ofL.salmonisat fish farms relies to a large extent on treatment with anti-parasitic drugs. A problem related to chemical control is the potential for development of resistance, which inL.salmonisis documented for a number of drug classes including organophosphates, pyrethroids and avermectins. The ATP-binding cassette (ABC) gene superfamily is found in all biota and includes a range of drug efflux transporters that can confer drug resistance to cancers and pathogens. Furthermore, some ABC transporters are recognised to be involved in conferral of insecticide resistance. While a number of studies have investigated ABC transporters inL.salmonis, no systematic analysis of the ABC gene family exists for this species. This study presents a genome-wide survey of ABC genes inL.salmonisfor which, ABC superfamily members were identified through homology searching of theL.salmonisgenome. In addition, ABC proteins were identified in a reference transcriptome of the parasite generated by high-throughput RNA sequencing (RNA-seq) of a multi-stage RNA library. Searches of both genome and transcriptome allowed the identification of a total of 33 genes / transcripts coding for ABC proteins, of which 3 were represented only in the genome and 4 only in the transcriptome. Eighteen sequences were assigned to ABC subfamilies known to contain drug transporters,i.e. subfamilies B (4 sequences), C (11) and G (2). The results suggest that the ABC gene family ofL.salmonispossesses fewer members than recorded for other arthropods. The present survey of theL.salmonisABC gene superfamily will provide the basis for further research into potential roles of ABC transporters in the toxicity of salmon delousing agents and as potential mechanisms of drug resistance

A comparative study of the semen and seminal characteristics of two breeds of goats (Zambia)

From a group of mature males goats of Boer and native Zambian goats, eight goats from each breed were selected and semen obtained by means of an electro-ejaculator. Two ejaculates were obtained each week at 24-hour intervals, for a total of six weeks. Ejaculate colours were strikingly variable between goats both within and among breeds, and also within ejaculates of the same goats collected on different days. Semen colour ranged from creamy-white to bright yellow. Boer goats yielded ejaculate volumes twice as large as those of native goats, although sperm motility were not different (P>0.5) between breeds, weeks or ejaculates. Approximately 65 per cent of all spermatozoa in the ejaculates of both breeds were of normal morphology and about 87 per cent were live. Sperm concentration was higher (

Factors affecting the calving rate in local breeds of cattle in Zambia

The reproductive performance of indigenous cattle in Zambia are examined. Information on general causes of infertility, age of puberty for males and females, oestrus cycle, pregnancy and calving rate of cows, and sperm production of bulls as well as chemical composition of semen are provided

The oestrus cycle of Zebu and Sanga breeds of cattle in Central Africa

The oestrus cycle and its manifestation in the Angoni, Barotse and Boran cattle are investigated. The time of onset and manifestation of oestrus and ovulation are observed, and changes in the size, colour, appearance and contents of the cervical organs reported

Effect of diminazene aceturate Isometamidium Chloride and Trypanosoma Brucei on epididiymal and testicular sperm reserves of mice

No Abstract. Bulletin of Animal Health and Production in Africa Vol. 50 (2) 2002: pp. 76-8