Farmers’ perceptions of goat kid mortality under communal farming in Eastern Cape,South Africa

Rearing of goats under communal farming conditions is characterised by high kid mortality and low weaning percentages. A survey was conducted to determine farmers’ perceptions on the causes of kid mortality during summer under the communal farming system in Nkonkobe Local Municipality in the Eastern Cape, South Africa. This was done by administering questionnaires to a total of 162 respondents in 14 villages around Nkonkobe Local Municipality. The study showed that majority of farmers (75 %) keep flock sizes of less than 10 goats and kids, and this indicates that goat production in Nkonkobe Local Municipality is suppressed. According to the farmers, diseases (89 %), endo-parasites (72 %) and ecto-parasites (68 %) were perceived as the major causes of kid mortality. Other causes reported include starvation (15 %), extreme weather conditions (28 %), abortion (7 %), theft (35 %), diarrhoea (43 %), accidents (10 %) and wounds (9 %). The low number of goats could be attributed to high mortalities. It was also found that all causes reported by farmers played a role in high kid mortality in Nkonkobe Local Municipality. However, the causes which require more emphasis to formulate extension support were tick-borne diseases and parasites. This study provided baseline information on possible causes of kid mortalities in Nkonkobe Local Municipality. There is, however, a need to conduct further studies to determine actual causes of high kid mortalities so as to develop preventive strategies that would minimize kid mortality for good economic returns.     

Calf survival and reproductive performance of Holstein–Friesian cows in central Ethiopia

This study was carried out to evaluate the reproductive performance and calves survival rate of Holstein–Friesian (HF) herd in Holeta, central highland of Ethiopia. A retrospective analysis of 26 years data was carried out, from which records of 724 age at first calving (AFC), 2,022 calving intervals (CI), 2,971 breeding efficiencies (BE), 260 abortions, 111 stillbirths were derived from 795 cows. Moreover, 738 female calves’ records were also included for survival rate study. The overall least squares means of AFC, CI, and BE were 40.9 ± 0.33 months, 475 ± 2.84 days, 81.9 ± 0.26%, respectively, while the incidence rates of abortion, stillbirth, and female calves survival rate for this herd were 8.0%, 3.4%, and 77.5%, respectively. The effects of parity number and year of birth/calving on CI and BE were significant (P < 0.001). Moreover, birth year had significant (P < 0.001) effect on AFC and calves survival rate, while calving season had significant effect on BE. The reproductive performance found in this study was lower than the performance reported in many tropical regions and the genetic potential of HF breed in their origins. Moreover, higher loss due to calf mortality was observed. Thus, the centre should consider appropriate measures to improve its herd reproductive performance and calves survival rate for attaining its aspired objectives.     

Farmers’ perceptions on trypanosomosis and trypanotolerance character of the taurine Sheko

In the humid and subhumid tropics, trypanosomosis is an economically important zoonotic protozoan disease of the commonly kept farm animal species and their wild relatives. For example, more than 20% of the humid western and southwestern Ethiopia, which is home to more than 14 million heads of cattle, is under varying levels of trypanosomosis risk. Our study was, therefore, initiated to document farmers’ perception on trypanosomosis and Sheko’s trypanotolerance character. Our findings showed that trypanosomosis was the most frequently reported cattle disease in the Bench Maji Zone. Accordingly, 76.7% of the farmers reported the epidemiological importance of trypanosomosis, and they also noted that trypanosomosis on average accounted for 63.0% of annualized cattle death. The reported signs of trypanosomosis and trypanotolerance indicators were consistent with literature reports. Moreover, 66.7% of the farmers reported Sheko’s trypanotolerance character. In the course of time, smallholder farmers have developed ethnoveterinary practices that are mainly used to prevent the landing of vector flies on the animal. Wet and warm seasons of the year, i.e., spring and, to some extent, the beginning of summer and autumn, were reported as peak periods of trypanosomosis risk. Therefore, this showed the need for incorporating farmers’ knowledge in trypanosomosis control programs.     

Beef traders’ and consumers’ perceptions on the development of a natural pasture-fed beef brand by smallholder cattle producers in South Africa

Beef traders’ and consumers’ perceptions on the development of a natural pasture-fed beef (NPB) brand by smallholder cattle producers were investigated. In total, 18 meat traders (five abattoirs and 13 beef retailers) and 155 beef consumers were interviewed using structured questionnaires. All meat traders had the potential but were not willing to support the development of a NPB brand citing smallholder farmers’ limited ability to supply sufficient volumes of high-quality cattle. Consumers (81%) were prepared to purchase NPB upon availability on the market but were not willing (80%) to pay a brand premium. Logistic regression model results showed that consumers’ willingness to buy NPB and pay a premium were influenced (P < 0.05) by gender, household size, income source, meat preference, meat consumption frequency, money spent on beef, frequency of beef purchases and consumption. Overall, beef traders and consumers held positive impressions regarding the development of a NPB brand by smallholder cattle producers but were not willing to support its development. Positive impressions held by value chain partners on the development of a NPB brand provide a basis for advancing development of a NPB brand. Initial efforts should enhance farmers’ capacity to supply sufficient volumes of high-quality cattle.     

The effect of non-genetic factors on the reproductive performance of Sanga and Friesian × Sanga crossbred dairy cattle breeds kept under hot and humid environment

A study was conducted to assess the effect of non-genetic factors on the reproductive performance of Sanga and Friesian?×?Sanga crossbred dairy cattle kept at Amrahia Dairy Farm, Ghana. Records on 66 crossbred Friesian?×?Sanga and 105 purebred Sanga cattle from 2005 to 2012 were used. The effect of sex of calf (male or female), season of calving (major, minor and dry), year of calving (2005–2012) and parity (first to third) on birthweight, calving interval and age at first calving were determined. The data were analyzed using the general linear model procedures of GenStat (Discovery Edition). The effect of parity of dam, year of calving, season of calving and sex of calf were considered as fixed effects for evaluating the different reproductive traits. Data on calving and conception rates over the period were 74.3 and 76.1 %, respectively. The overall mean values for birthweight, age at first calving and calving interval obtained were 23.9?±?1.5 and 22.8?±?1.4 kg, 38.8?±?2.5 and 40.2?±?2.4 months and 390.8?±?12.5 and 413.6?±?12.1 days for the crossbred and Sanga, respectively. It was observed that all the major determinants of reproductive performance studied apart from birthweight were significantly influenced by year of birth, parity, season of calving and sex.     

Relationship between ketosis and dairy cows’ blood metabolites in intensive production farms of the periurban area of Dakar

This study which involved 140 Holstein and Montbeliard was carried out in the periurban area of Dakar with the aim to establish the relationship between ketosis, milk production and biochemical blood metabolites. The results showed that ketosis is a real problem in periurban farms around the city of Dakar with high proportions of 33.57% for subclinical ketosis and 6.43% for clinical ketosis. In their second month of milking, cows with subclinical ketosis had a decrease of 12.4 and 15.,6% in milk yield respectively for Montbeliard and Holstein, whereas cows with clinical ketosis had a decrease of 18.6 and 26%. Ketogenic cows (subclinical and clinical) have significantly lower average levels of blood glucose (p<0.05) and significantly higher average levels of blood urea (p<0.05) than cows with normal blood beta-Hydroxy Butyrate (BbHB) levels. Also, from one farm to another, significant difference was recorded with concentration of total proteins and globulin, calcium and magnesium.     

Seroprevalence of Neospora caninum antibodies and its consequences for reproductive parameters in dairy cows from Dakar–Senegal,West Africa

The aim of this study was to determine the seroprevalence of Neospora caninum antibodies and its effects on reproductive parameters in cows in intensive dairy herds in Dakar. Randomised blood samples were taken for serology from 196 cows in four herds with a history of sporadic abortion. All of the sera were assayed for antibodies against N. caninum, Candida guillermondii, Coxiella burnetii, and Chlamydophila sp. The associations between serostatus and reproductive parameters (abortion, number of inseminations to conception, and calving to conception interval) were assessed over a period of 5 years (2004–2008). The seroprevalence of N. caninum antibodies in dairy cattle was 17.9%. The local Gobra breed and crossbreeds had higher levels of N. caninum antibodies than exotic breeds (p < 0.05). For the most recent pregnancies, seropositive cows required more inseminations to establish conception than seronegative cows (p < 0.05). The results indicate that dairy cattle from Dakar are exposed to N. caninum. Neosporosis should, therefore, be systematically considered as a cause when the calving to conception interval is prolonged.     

A comparison of the effects of two low‐calcium diets on egg production in the domestic fowl

1. Hens fed on a diet containing 0–05% calcium virtually ceased egg laying (production <4%) whereas those fed on a diet containing 0–5% Ca maintained production at between 20 and 30%.

2. After a return to a normal diet (3% Ca) egg weight, shell weight, ovarian characteristics and oviduct size were of a similar nature in the two groups, though the differences in egg weight, shell weight and shell calcium were significant at the 1 % level.

3. Bone weight and bone ash did not differ significantly between the groups but after a return to normal rations, bone weight and bone ash became higher in the group that had received the 0.05% Ca diet.

4. There were no clinical signs of bone demineralisation during the experiments.     

Drivers and trajectories of social and ecological change in the Karoo,South Africa§

This review article explores past, present and possible future drivers of change in Karoo social-ecological systems. Biogeographically, the Karoo comprises the arid Succulent Karoo and Nama-Karoo biomes covering significant portions of the Northern Cape, Eastern Cape and Western Cape provinces and a smaller part of the Free State. Despite the Karoo’s specific environment and spatial importance nationally (covering some 30% of South Africa), no government structures address its needs holistically. Today it is a politically and economically marginalised region; perceptions of it as a desert easily morph into perceptions of it as deserted and ripe for exploitation for the benefit of external constituencies, whether in the name of astronomy, shale-gas and uranium mining or renewable energy. To manage the Karoo better for present and future generations, it is clearly desirable for social and natural scientists to work collaboratively, yet there is relatively little interdisciplinary work to date. Against this background this review article provides an overview of social and ecological changes historically and in the present, and offers some cautious reflections concerning climate change, changing land use and governance as key drivers affecting trajectories of change into the future.     

Communal farmers’ ecological knowledge and perceptions of grasses in the central Eastern Cape province,South Africa: similarities with field studies and scientific knowledge and their implications

The local ecological knowledge (LEK) and perceptions of grasses were investigated in six semi-arid communal areas in the central Eastern Cape province, South Africa, and compared with field studies and scientific knowledge. Of the total of 21 grasses identified in the field survey, communal farmers had vernacular names only for 11 species. Respondents rated Digitaria eriantha and Pennisetum clandestinum to have the highest (p < 0.05) grazing value. Respondents’ ratings of Eragrostis obtusa and Sporobolus africanus as having similar (moderate) grazing values to Themeda triandra is against the established knowledge. Respondents’ ratings of T. triandra and S. africanus as having higher (p = 0.01) ecological value than the other grasses concur with the scientific knowledge, whereas their nomination of E. obtusa and D. eriantha as providing less ecological benefits than Aristida conjesta disagrees with some ecologists. The study hinted at the complementarity and discrepancies between LEK and scientific knowledge that need ratification. The respondents’ lack of detailed knowledge is suggestive of a gradual eroding of LEK among the local communities that will adversely impact the local people’s ability to implement sustainable rangeland utilisation practice. The current study also recognised farmers’ familiarity as well as training needs that would expound their knowledge and management of grasses.     

Does virginiamycin supplementation affect the metabolism and performance of Nellore bulls grazing under low and high gain rates?

This study aimed to evaluate the effect of virginiamycin on the metabolism and performance of growing Nellore bulls under low and high gain rates on pasture. In experiment 1, 80 Nellore bulls (age = 12 ± 2 months, body weight = 258 ± 15 kg) were assigned to 16 paddocks in a 2 × 2 randomized block factorial arrangement. In experiment 2, 12 cannulated Nellore bulls were assigned to three 4 × 4 balanced Latin squares. The factors were: (1) mineral salt without or with virginiamycin, and (2) low or high gain rate. No interaction was noted between factors (p > .10). Animals fed virginiamycin had greater average daily gain (14%, p < .01), body weight (11 kg, p = .05), plasma nonesterified fatty acid (20%, p < .01), serum calcium concentration (2.62%, p = .04), and total protozoa (p = .03) and had the same bacterial proportion (p > .27). Animals with a low gain rate had greater serum urea concentration (19.6%, p < .01) and ruminal ammonia nitrogen (62%, p < .01). Thus, virginiamycin increases the performance and changes the metabolism of growing Nellore bulls under low and high gain rates on pasture.     

A survey of the prevalence of blowfly strike and the control measures used in the Rûens area of the Western Cape Province of South Africa

Blowfly strike and the methods used to combat blowfly strike were recorded on 33 properties in the R?ens area of South Africa during 2003/2004. Data were recorded on Merino and Dohne Merino hoggets (n = 4951) with at least 3 months' wool growth. The following data were captured: presence or absence of strike, site of the strike (body or breech), presence or absence of dermatophilosis as well as subjective scores for wool quality and wool colour. Control measures recorded include: chemical treatment (preventative and spot treatment), crutching, mulesing and the use of the Lucitrap system. Blowfly strike was not significantly influenced by gender or breed. Hoggets suffering from dermatophilosis were more likely to be struck, compared with contemporaries not suffering from the skin disorder (0.057 vs 0.027; P < 0.05). Merino hoggets generally had higher scores than their Dohne Merino contemporaries for wool quality (32.6 vs 27.4; P < 0.05) and wool colour (29.0 vs 27.2; P < 0.05). There was an indication that the Lucitrap system may have reduced flystrike, but the effect was not statistically significant (P = 0.19 for overall strikes and P = 0.12 for body strike). The Mules operation benefited overall flystrike (0.013 vs 0.110; P < 0.05); mainly through an effect on breech strike (0.010 vs 0.109; P < 0.05). The proportion of fly strikes increased with wool length, and declined with an increase in farm size in wool colour score. None of the ethically acceptable control measures assessed could substantially reduce blowfly strike on their own, and an integrated pest management programme was proposed.     

Influence of fibrolytic enzymes in total mixed ration containing urea-molasses-treated sugarcane bagasse on the performance of lactating Holstein–Friesian crossbred cows

The aim of this study was to determine the effect of different levels of fibrolytic enzyme on nutrient utilization and milk production in dairy cows. Four multiparous early-to-mid-lactation Holstein–Friesian crossbred cows were randomly allocated in a 4 × 4 Latin square design. Cows were fed a balanced total mixed ration (TMR) on a dry matter (DM) basis containing 0, 1.2, 2.4, and 3.6 g/kg DM of fibrolytic enzyme in TMR, where the TMR comprises 60% concentrate supplemented with a fibrolytic enzyme at 0, 2, 4, and 6 g/kg DM of concentrate, and 40% urea-molasses-treated sugarcane bagasse (UMSB) was used as a roughage source. Fibrolytic enzyme supplementation in TMR containing UMSB did not affect dry matter intake (DMI) of dairy cows (p > 0.05). There was a quadratic effect of fibrolytic enzyme levels on the digestibility of DM, organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) (p < 0.05), and the maximal response was reached at 1.2–2.4 g/kg DM of fibrolytic enzyme added in the TMR. Furthermore, 3.5% fat-corrected milk, milk fat, total volatile fatty acids, and propionic acid were greater in a cow fed with 1.2–2.4 g/kg DM of fibrolytic enzyme, resulting in a lower ratio of acetic acid to propionic acid (p < 0.05). In conclusion, adding a fibrolytic enzyme in TMR containing UMSB improved nutrient utilization, rumen fermentation, and milk production of lactating dairy cows.     

Assessing the success of experimental rehabilitation on a coastal mineral sands mine in Namaqualand,South Africa§

The success of different rehabilitation treatments following surface mining on the arid west coast of South Africa was assessed. Treatments consisting of one or a combination of topsoil addition, plant translocation and seeding were applied to experimental rehabilitation sites in 2001, while the treatment of another site in 2008 combined all three techniques. Vegetation and species cover, species richness, diversity and evenness, and grazing capacity of rehabilitation sites were sampled during winter 2009 and summer 2010, and compared with a reference site. All rehabilitated sites achieved the objective to attain a minimum grazing capacity of 20 ha per small stock unit. Rehabilitation trials were successful in establishing a vegetation cover, but were unable to return species richness and diversity to reference levels and did not resemble the reference site in species composition. Common species in reference sites were absent or only occurred in low numbers. No treatment outperformed the others and further experimentation is needed to determine the most suitable combination. It is recommended that rehabilitation should be done in multiple stages in future to improve seedling survival and to return species that are unable to establish in the adverse conditions present at the onset of rehabilitation.     

The effect of delaying the onset of laying in pullets with a low‐calcium diet on subsequent egg production

1. A low‐calcium diet (0.5 g calcium/kg) was used to prevent the onset of laying in young pullets.

2. It was fed at 16 weeks of age to five separate groups (groups 2 to 6) each of 50 to 60 birds.

3. Group 2 was fed on a normal layers’ diet at 23 weeks of age, group 3 at 27 weeks, group 4 at 31 weeks, group 5 at 35 weeks and group 6 at 55 weeks while the control group (group 1) of similar size to groups 2 to 6 was subjected to a normal commercial treatment for laying stock.

4. In all the experimental groups the onset of sexual maturity occurred normally, but only one or two eggs were laid before laying ceased under the influence of the treatment.

5. Laying re‐started when the hens were fed on a normal diet and production rapidly rose to a high level.

6. Groups 1, 2 and 3 differed little in the total number of eggs produced up to 72 weeks of age.

7. In all experimental groups there were fewer very small, small and medium eggs than in the control group.

8. It is suggested that the use of a low‐calcium diet before the onset of lay may have advantages which could be exploited on a commercial scale.     

Near-shore distribution of Heaviside’s (Cephalorhynchus heavisidii) and dusky dolphins (Lagenorhynchus obscurus) at the southern limit of their range in South Africa

Photo-identification surveys over three years along 390 km of coastline north of Cape Town, revealed that Heaviside’s dolphin distribution was consistent between years and higher in areas more exposed to swells and with greater long-term availability of small hake Merluccius capensis (their principal prey). Dusky dolphin sighting rates varied considerably between years, but were generally higher in areas with lower hake availability and sandier shores (mostly straighter coastline). Large groups of 50–200 dusky dolphins were only seen in St Helena Bay, the site of a wind-driven upwelling zone. Heaviside’s dolphins were found in shallower, cooler water than dusky dolphins and were more likely to be seen during brighter phases of the moon (when nocturnal light conditions may influence the vertical migration patterns of prey) and in areas of high hake abundance. Near-shore fishing activity was higher in the northern half of the study area and clustered around harbours. Set netting occurred only at Yzerfontein and St Helena Bay, but due to changes in the industry is currently thought to be a low threat to the population. Interactions between Heaviside’s and dusky dolphins were usually neutral and sympatry appears to be mediated by differences in overall range and the type and size of prey species taken.     

Vegetation responses to seasonal weather conditions and decreasing grazing pressure in the arid Succulent Karoo of South Africa§

The Succulent Karoo biome is a renowned centre of biodiversity and endemism in the arid winter rainfall region of South Africa that is threatened by climate change. On 20 permanently marked plots within a biodiversity observatory, species richness and cover were assessed annually from 2002 to 2017 during the growing season. We were interested, firstly, in whether the vegetation showed any trends in response to the strong decrease in grazing pressure, which occurred at the beginning of the monitoring period, and secondly, in the effect of seasonal climate on the vegetation. We analysed the responses of species richness and cover in four life forms to seasonal rainfall and the standardised precipitation–evapotranspiration index (SPEI) using linear mixed-effect models. Time had a positive effect on richness of annual species and a negative effect on cover of shrubs and annuals, which increased in response to SPEI and less strongly to rainfall during autumn and winter. Habitat did not have any effect and geophytes and perennial herbs did not show any significant response. The importance of SPEI during autumn and winter is discussed in relation to potential germination cues and the projected decrease in rainfall and increase in temperature during these seasons.     

Finding best exotic breed proportion in crossbred lactating sheep kept under farmers’ conditions in Ethiopia determined by use of nested Legendre polynomials with limited data

ABSTRACT

The present study was conducted to estimate milk production performance and fit lactation curves for groups of ewes of Local and of Awassi crosses, with a variable blood level, reared under farmer’s environment. The Weigh-Suckle-Weigh method plus hand milking was used to estimate milk yield for ewes. A total of 466 observations from 115 ewes were used. Estimated least-squares adjusted means for the milk production over 120 days were 0.56?kg day^?1 (Local), 0.67 (<30% Awassi), 0.86 (30–50% Awassi), and 0.96 (>50% Awassi). Groups with 30–50% Awassi and >50% Awassi ewes produced significantly (p?<?0.05) more milk than Local ewes. Significant differences were observed between <30% Awassi and >50% Awassi crossbred groups. The best crosses (>50% Awassi) produced over 70% more milk than the local ewes which demonstrates the potential that exists in increasing milk production through the initiated crossbreeding programme with sheep in Ethiopia.