Breeding programmes for smallholder sheep farming systems: II. Optimization of cooperative village breeding schemes

A simulation study was conducted to optimize a cooperative village‐based sheep breeding scheme for Menz sheep of Ethiopia. Genetic gains and profits were estimated under nine levels of farmers' participation and three scenarios of controlled breeding achieved in the breeding programme, as well as under three cooperative flock sizes, ewe to ram mating ratios and durations of ram use for breeding. Under fully controlled breeding, that is, when there is no gene flow between participating (P) and non‐participating (NP) flocks, profits ranged from Birr 36.9 at 90% of participation to Birr 21.3 at 10% of participation. However, genetic progress was not affected adversely. When there was gene flow from the NP to P flocks, profits declined from Birr 28.6 to Birr ?3.7 as participation declined from 90 to 10%. Under the two‐way gene flow model (i.e. when P and NP flocks are herded mixed in communal grazing areas), NP flocks benefited from the genetic gain achieved in the P flocks, but the benefits declined sharply when participation declined beyond 60%. Our results indicate that a cooperative breeding group can be established with as low as 600 breeding ewes mated at a ratio of 45 ewes to one ram, and the rams being used for breeding for a period of two years. This study showed that farmer cooperation is crucial to effect genetic improvement under smallholder low‐input sheep farming systems.     

Defining a breeding objective for Nile tilapia that takes into account the diversity of smallholder production systems

In general, livestock and fish farming systems in developing countries tend to be highly diverse in terms of agro‐ecological conditions and market orientation. There are no studies that have investigated if and how this diversity translates to varying preferences for breeding objective traits. This is particularly important for breeding programmes that are organized on a national level (e.g. government‐supported nucleus breeding programmes). The aim of this study was to investigate whether Nile tilapia farmers with diverse production systems and economic constraints have different preferences for breeding objective traits. The second objective was to derive a consensus breeding goal, using weighted goal programming that could be used for a national breeding programme for Nile tilapia. A survey was conducted among 100 smallholder Nile tilapia farmers in Kenya to obtain preference values for traits of economic importance, by using multiple pairwise comparisons. Individual and group preference values were estimated using analytical hierarchy process. Low‐income farmers preferred harvest weight, while medium‐ and high‐income farmers preferred growth rate and survival. Grouping farmers according to market objective (fingerling production or fattening) showed that fingerling producers preferred growth rate and survival, while fattening farmers preferred harvest weight, height and thickness. Weighted goal programming was used to obtain consensus preference values, and these were used to derive desired gains for a breeding goal of a national breeding programme that takes into account the diversity of smallholder production systems.     

Breeding programs for smallholder sheep farming systems: I. Evaluation of alternative designs of breeding schemes

Village‐ and central nucleus‐based schemes were simulated and evaluated for their relative bio‐economic efficiencies, using Ethiopia's Menz sheep as example. The schemes were: village‐based 2‐tier (Scheme‐1) and 1‐tier (Scheme‐2) cooperative village breeding schemes, dispersed village‐based nuclei scheme (Scheme‐3), conventional 2‐tier central nucleus‐based scheme (Scheme‐4), and schemes linking a central nucleus and village multiplier nuclei with selection in central nucleus (Scheme‐5) or in both central and village nuclei (Scheme‐6). Among village‐based schemes, Scheme‐1 gave the highest genetic progress, while Scheme‐2 was economically the most efficient with genetic gain in the breeding objective of Birr 5.6 and a profit of Birr 37.2/ewe/year. The central nucleus schemes were more efficient than the village schemes. Scheme‐4 was the most efficient with genetic gain in the breeding objective of Birr 13.5 and a profit of Birr 71.2, but is operationally more difficult as it requires a very large central nucleus. The choice between village and central nucleus‐based schemes would depend on local conditions (availability of infrastructure, logistics and technical knowhow and support). Linking central nucleus with village‐based nuclei (Scheme‐6) would be a feasible option to overcome the operational difficulties of the conventional central nucleus scheme. If a village‐based breeding program is envisaged as should be the 1st step in most low‐input systems, then Scheme‐2 is the most efficient. To scale out to an entire Menz breed level, Scheme‐3 would be recommended.     

Calf morbidity,mortality and parasite prevalences in the cotton zone of Burkina Faso

The objective of this study is to describe morbidity and mortality in calves <1-year-old and to associate the impact of gastrointestinal and haemoparasitoses on morbidity and mortality by comparing these parameters in ill and well calves in the cotton zone of Burkina Faso. Fifty-nine herds selected in two villages were involved. Calves born between February 1997 and February 1999 were monitored up to 1 year of age or until the end of the study in April 1999. Blood and faecal samples were taken from ill calves and matched with samples taken from well calves (as control) for analysis of haemoparasites and gastrointestinal worms. Infected ill calves were treated with a trypanocidal drug and/or an anthelmintic. Dead calves were necropsied; adult-worm burdens were determined and brain smears taken to detect the presence of Cowdria ruminantium. Diarrhoea was the main clinical observation and most calves shed worm eggs. The EPG for gastrointestinal parasites was higher neither in ill calves nor in diarrhoeal calves. Infections by trypanosome species were observed in ill calves only (prevalences of 8% and 15% in Daboura and Kourouma, respectively). Average PCV in infected calves (28%) was lower than that in non-infected calves (37%). Most ill calves (86%) recovered 2 weeks after the treatment with anthelmintic and/or trypanocide. The post-mortem worm counting in 12 calves revealed that half of necropsied calves had a burden ranging from 2040 to 20,072 helminths. Infection by Babesia bigemina was found in the blood smear of one ill calf and the presence of C. ruminantium was noted in the brain smear of one calf.     

Production objectives and breeding goals of Sahiwal cattle keepers in Kenya and implications for a breeding programme

The Sahiwal breed has been used for upgrading the East African Zebu (EAZ) for improved milk production and growth performance in the southern rangelands of Kenya. Main users of this breed are Maasai pastoralists. Until now, there has been no deliberate effort to understand why these pastoralists specifically prefer to keep Sahiwal genetic resources as well as which traits are considered important by them and what is the underlying reason for this. However, this information is regarded vital for further development of the breed. A survey was conducted between May and October 2009 among Maasai pastoralists in Kajiado and Narok counties in the Southern part of Kenya, and private ranches and government farms to identify production objectives and breeding goals of Sahiwal cattle producers. Sahiwal genetic resources were mainly kept for domestic milk production and for revenue generation through milk sales and live animals. To a limited extent, they were kept for breeding and also for multiple objectives that included insurance against risks and social functions. Production aims were influenced to varying extents by various household and farmer characteristics. Sahiwal cattle and their crosses were generally perceived to be better with respect to productive traits and fertility traits when compared to the EAZ. However, the EAZ was rated higher with respect to adaptation traits. The breeding objective traits of primary importance were high milk yield and big body size, good reproductive efficiency and relatively good adaptation to local production conditions. Performance and functional traits are important breeding goals that play a major role in fulfilling the multiple production objectives. This forms the basis for the optimisation of a breeding programme for sustainable utilisation to meet the needs of Sahiwal cattle producers.     

Characterization of the production system and breeding practices of indigenous goat keepers in Hai district,Northern Tanzania: implications for community-based breeding program

Indigenous breeding practices of the farmers and the livestock production system form the bases for designing community-based breeding programs. The aim of this study was to characterize production system and examine breeding practices of the indigenous goat farmers in Hai district in Northern Tanzania to determine their relevance in establishing a community-based breeding program in the area. A cross-sectional survey was conducted in which information was collected from 160 households randomly selected from 6 villages. Average household herd was 29.2 goats with majority keeping less than 20 goats. Major reasons for keeping goats were income generation, meat and milk production. Controlled mating was practiced mainly using apron and castration. Castration was practiced using traditional methods to control breeding and improve meat quality. Farmers in the study area had large goat flocks and a small buck to doe ratio. Farmers do not have a good understanding of inbreeding and its negative effects but practise other good breeding methods which could impact the productivity of their animals. Diseases and feed shortages were the main constraints to production. Opportunities exist for a community-based breeding program to genetically improve goat productivity.

     

Brucella ovis excretion in semen of seronegative, clinically normal breeding rams

A commercial flock of Suffolk and Suffolk-cross breeding rams was monitored for 5 years in an effort to control epididymitis caused by Brucella ovis. Scrotal palpation, semen evaluations, and vaccination against B ovis were used the first 3 years. Serologic evaluation (complement fixation and ELISA) was added the fourth year, and bacteriologic culturing was added to the program the fifth year. Semen culturing in the fifth year revealed 9 (37.5%) of 24 rams were actively excreting B ovis; 6 of those 9 rams were seronegative. Neither semen quality nor the presence of WBC in the semen were dependable criteria to detect these seronegative carriers. In spite of the high percentage of B ovis excretors, few clinical signs of epididymitis were detected in the flock during the last 3 years of the study. It was hypothesized that vaccination protected rams against the clinical disease but not the carrier state. The importance of culturing semen for assessment of a control program was emphasized.     

Genetic diversity and population structure of South African smallholder farmer sheep breeds determined using the OvineSNP50 beadchip

Tropical Animal Health and Production - A population structure study was performed in South African ovine populations using the OvineSNP50 beadchip. Blood samples were obtained from 295 sheep of...     

A comparison of submicroscopic changes in the testes of rams after experimental ischemia with findings in orchitis in breeding rams

Submicroscopic changes in the testes of rams were studied after experimental ischaemia induced by ligature on a. testicularis. The obtained findings were compared with those after traumatic orchitis in breeding rams. Both groups of animals showed marked changes in the germinal as well as Sertoli cells, which were characterized by generalized vacuolization of cell cytoplasm, accompanied by cell caryolysis. The Sertoli cells showed lipid cumulation and glycogen multiplication. The tubule wall had undulated layers. A pronounced reduplication of the lamellar layer of the tubule wall was recorded in the rams with orchitis. The interstitial tissue shows multiplication of collagenous fibres. The findings warn against traumatic injury of testes. The disordered spermiogenesis is irreversible.     

Melatonin improves testicular haemodynamics,echotexture and testosterone production in Ossimi rams during the breeding season

The objective was to determine effects of a single parenteral dose of melatonin on testicular blood flow indices, testicular echogenicity and plasma testosterone concentrations in rams during the physiological breeding season. We hypothesized that melatonin enhances testicular blood flow, echogenicity and plasma testosterone concentrations during the breeding season in rams. During the breeding season, 12 sexually mature Ossimi rams were randomly allocated to either a melatonin group (n = 8) that received 18 mg of melatonin in 1 ml of corn oil (injected SC) or a control group (n = 4) that received 1 ml corn oil only. Blood collection and ultrasonographic assessment of the testes and supratesticular arteries were conducted immediately before treatment (W0) and once weekly for 6 weeks after melatonin injection (W1-W6). Mean plasma testosterone concentrations were greater (p < .05; at least 1 ng/ml) in the melatonin-treated group compared to the control group from W4 to W6 after treatment. A decrease (p < .05) in both resistive index (RI) and pulsatility index (PI) began 1 week after melatonin injection (W1) and persisted until the end of the experiment, with mean RI and PI values in the melatonin group lower (p < .05) than those in the control group on W3 and W4. Furthermore, plasma testosterone concentrations in melatonin-treated rams were inversely correlated to both RI and PI (r = −.7 and −.6, respectively, p < .01). Testicular echogenicity decreased (p < .05) 1 week after melatonin injection (W1) and remained lower (p < .05) in the melatonin-treated group compared to the control group until the end of the study (W6). In conclusion, melatonin administration significantly altered testicular blood flow and echogenicity and increased plasma testosterone concentrations in Ossimi rams during the breeding season.     

Controlled breeding in sheep using the prostaglandin analogue,ICI 80996

A series of experiments was conducted to investigate the potential of an analogue of prostaglandin-F_{2 α}, namely ICI 80996, to control ovulation in the cyclic ewe. A single intramuscular injection of 100 μg of this material during the mid-luteal phase of the oestrous cycle resulted in rapid luteolysis with a consequent synchronised return to oestrus. Moreover, the endocrine changes during the induced cycle were not significantly different from those during a natural cycle. Two injections given 9 days apart controlled ovulation in all ewes no matter what stage of the cycle treatment commenced. There was a high degree of synchrony in the return to oestrus following the second injection (38.6 ± 0.8 h) and the time interval from injection to ovulation (72.9 ± 1.5 h). Fertility of treated ewes to natural service was not significantly different from controls when assessed in terms of both the conception rate (68 vs 710, respectively) and prolificacy (147 vs 141%, respectively).     

Epidemiology and microscopic diagnosis of tuberculosis in pigs and small ruminants slaughtered at Bobo-Dioulasso abattoir,Burkina Faso

Bovine tuberculosis (bTB) is a zoonotic, infectious, chronic and contagious disease, caused by Mycobacterium bovis that mainly affects cattle. This pathology has a negative impact on animals and animal products trade. Unfortunately, in Burkina Faso where agriculture and livestock sectors represent around 80% of the socio-economic activities, the real situation of the disease is not well known especially in small ruminants and swine. Thus, our study focused on both the epidemiology and the microbiological diagnosis of tuberculosis (TB) in small ruminants and pigs slaughtered at Bobo-Dioulasso abattoir. A prospective study was conducted between August 2017 and December 2017. Epidemiological data collection was performed during routine meat inspection; moreover, samples were taken and transported to the Bacteriology laboratory of Centre Muraz for microbiological analyses. This diagnosis consisted in search of Acid Fast Bacilli (AFB) using the hot Ziehl–Neelsen staining. Out of a total of 14 648 small ruminants and 2430 pigs slaughtered during the study period, 156 and 17 had lesions suggestive of bTB with prevalence of 1.07% and 0.7%, respectively. Females and those between 2 and 4 years old were mainly infected. The most affected organs were: lungs, liver, spleen and lymph nodes. Finally, microscopy revealed 43.35% (75/173) of positive cases for AFB. These results confirm the presence of bTB in small ruminants and pigs in Burkina Faso. Efforts must still be made in the fight against this zoonosis in order to limit its economic and public health impacts.     

Scavenging Pullets in Burkina Faso: Effect of Season,Location and Breed on Feed and Nutrient Intake

A study on scavenging local (n = 64) and crossbred (n = 64) pullets was undertaken in the dry and rainy seasons in two villages in Burkina Faso: Korea in the arid northern Sahelian region and Bounouna in the sub-humid south. After 4 weeks of scavenging, the birds were killed and the crop contents were subjected to physical and chemical analysis. Cereal grains, brans, green and dry forages, insects/worms and household leftovers were the main physical components. The proportion of cereal grains was higher in the rainy season, whereas the proportion of bran, peanut and sand/grit was higher in the dry season (p < 0.05). The proportion of kitchen waste and millet/milo grains was higher in local than in crossbred birds, whereas the opposite was the case for millet/milo bran (p < 0.05). Rice and local beer residues were not found in the crops of birds from Korea. Dry matter, ash, crude fibre and potassium contents were higher in the dry season (p < 0.05), while calculated metabolizable energy content was higher in the rainy season (p < 0.05). There were no location or breed effects on chemical composition parameters (p > 0.05), except that potassium content was higher in Korea. Mean live weight at slaughter was 806 ± 22.0 g (local breed) and 881 ± 22.0 g (crossbreds) (p < 0.05). Digestive organ weights, including contents, were higher for crossbred birds (p < 0.05). Gastrointestinal tract percentage was higher in the rainy season and in Bounouna (p < 0.05). The nutrient composition of the crop contents indicates the need for supplementation, particularly of protein, for higher levels of production.     

Assessing actors in rural markets of sheep and goats in the Nyando Basin of Western Kenya: a key to improving productivity from smallholder farms

Livestock traders are a key conduit for incentives in livestock production systems. Their actions affect producer prices, investment decisions, and their livelihoods. However, smallholder farmers in rural communities of eastern Africa often have limited understanding of the marketing process and the interactions among market actors. This study was undertaken following the introduction of improved indigenous goat and sheep breeds in Climate Smart Villages of Nyando in western Kenya. We sought to understand the marketing of sheep and goats in five key rural markets used by the smallholder farmers of Nyando, to generate information on key market actors, their functions in the value chain, and their preferences for attributes in sheep and goats. Most traders (65%) in all the markets were men. Four different types of traders operated in the markets, producers, retailers, wholesalers, and brokers, each making a profit. Preference for selling sheep or goats and the animal attributes desired by the traders differed depending on the surrounding community. Markets in Kericho County of Nyando traded more goats than sheep while those in Kisumu County of Nyando traded more sheep than goats. There were no clear policies guiding pricing of animals. Prices offered to producers depended on previous days, and the number of animals available for sale at the marketing point. The collaborative group actions of the producers in the Climate Smart Villages did not extend beyond the level of production to the marketing of their livestock. A critical change is required for the smallholder farmers to derive better incomes from improved quality of animals following adoption of improved breeding and management practices. The results illustrate the need to engage rural market actors when implementing livestock improvement programs for smallholder farmers for better farm gate prices of animals, and thus achieve the improved incomes envisioned.     

Lincomycin and spectinomycin in the treatment of breeding rams with semen contaminated with ureaplasmas

Ureaplasma species were isolated from semen samples collected sequentially from one Awassi and three Assaf breeding rams. Each ram was injected subcutaneously with an aqueous solution of lincomycin and spectinomycin for five consecutive days at a dose equivalent to 4·5 mg kg⁻¹ lincomycin and 9·0 mg kg⁻¹ spectinomycin daily. Serum and semen samples were collected at intervals during the treatment and assayed for lincomycin. No Ureaplasma species were isolated from semen samples collected during the course of the treatment and at intervals for 17 days after the last treatment. The concentration of lincomycin in semen ranged from 0·51 μg ml⁻¹ four hours after treatment to 0·08 μg ml⁻¹ 24 hours after treatment, and these levels were three to nine times higher than the corresponding serum concentrations.     

Influence of high risk exposure to trypanosoma infection on the reproduction of the Baoulé cattle in Burkina Faso

Trypanosome infection influences reproductive function in trypanotolerant as well as trypanosensitive cattle. Abortions and anoestrus behaviour have been noted in short horned Baoulé cattle in high risk areas of trypanosome infestation. These reproductive disturbances, which are systematically encountered in sensitive animals as well as some resistant animals, seem to be linked with a degradation in the physical state of the animal, anemia, and hyperthermia. Finally, a considerable amount of individual variation has been reported in what concerns the animals response to trypanosome infection.