Effect of housing improvement and other factors on the growth of heifer calves on Kenyan smallholder dairy farms.

This trial evaluated average daily gain (ADG) effects of heifer calves (< 1 year old) from affordable housing improvements to the roof and flooring on 150 randomly allocated smallholder dairy farms. During the 16-month data collection period, bimonthly farm visits were used to measure weight and other animal- and farm-level factors on the 187 study calves. Multivariable linear regression was used to model ln ADG and ADG during pre-weaning and post-weaning periods, respectively. Median pre-weaning and post-weaning ADGs were 0.307 (interquartile range (IQR): 0.227-0.398) and 0.487 (IQR: 0.354-0.675) kg/d, respectively. In the final pre-weaning model (p<0.050), factors positively associated with ln ADG were calf age at first acaricide application, and total number of calf pens, while factors negatively associated with ln ADG included calf mortality risk over the last 5 years and calf age at first ad lib access to water. In an interaction term, for calves from parity 3+ dams, ADG was lower when milk was fed twice/day than thrice/day, with no difference in calves of lower parity dams. In the final post-weaning model, housing improvements increased ADG by 5.6%. Other factors positively associated with post-weaning ADG were feeding of calf pellets, wheat bran, maize bran, and hay. Calf age at first introduction of concentrate and calf mortality risk over the last 5 years were negatively associated with ADG. In an interaction term, ADG was high when there were faecal coccidia oocysts and when calves had visual or physical contact with their dams, but low when faecal coccidia cysts were present, and these dam-calf connections were absent. In a second interaction term, ADG increased with more calf pens for female principal farmers, while remaining low for male principal farmers. In conclusion, while controlling for other factors of ADG, making affordable calf housing improvements enhanced ADG, particularly during the post-weaning period.

Factors influencing economic efficiency of milk production among small-scale dairy farms in Mukurweini, Nyeri County, Kenya.

This paper highlights the factors likely to influence the economic efficiency of small-scale dairy farms in Mukurweini, Nyeri County, Kenya. A total of 91 small-scale dairy farms previously involved in a nutritional training in 2013 were administered with semi-structured questionnaires. Data collected were entered into SPSS and FRONTIER 4.1 was used to compute the technical, allocative and economic efficiency scores for each farm. The scores were then regressed against a set of variables using the Tobit model in STATA to determine the factors associated with the scores. The average age of the household members involved in dairy farming, household size, labour, cost of concentrates and size of land owned had a negative significant influence on economic efficiency. It was concluded that lowering costs, proper utilization of hired labour and intensive use of the available land for dairy farming would lead to an increase in economic efficiency. The study recommends subsidized prices for concentrates, intensive dairy farming, minimization of hired labour and organization of dairy training and workshops in order to increase the efficiency of milk production in small-scale farms in the study area and other parts of Kenya with similar agro-ecological and cultural conditions.

Seroprevalence and risk factors associated with Theileria parva infection among calves in Narok County, Kenya.

Background and Aim: East Coast fever (ECF), caused by Theileria parva, is a devastating disease that causes significant economic losses to cattle production in sub-Saharan Africa. Prevention and control of ECF are challenging in pastoral settings due to inadequate epidemiological information. This study aimed to estimate the seroprevalence and risk factors associated with T. parva infection among calves in different production systems to help design appropriate control interventions. Materials and Methods: Blood samples were collected from 318 calves and tested using an indirect enzyme-linked immunosorbent assay targeting antibodies against polymorphic immunodominant molecules found on the surface of T. parva. Information on calf characteristics and management practices was also collected during sampling. Descriptive statistics and logistic regression were used to analyze potential risk factors, such as age and acaricide application, where p < 0.05 was considered significant. Results: Of the 318 calves sampled, 41 (12.89%) were positive for T. parva, with a higher proportion in pastoral systems (36.58%) than in mixed farming systems (34.10%) and agropastoral systems (29.27%). From univariate analysis, calf age (p = 0.002), body weight (p = 0.001), suckling status (p = 0.026), rectal temperature (p = 0.06), calves on pasture (p = 0.022), other feeds (p = 0.004), feed grown within the farm (p = 0.004), acaricide application (p = 0.001), and acaricide application frequency (p = 0.001) were significantly associated with seropositivity. However, calf age (odds ratio [OR], 0.96; 95% confidence interval [CI], 0.91-0.99; p = 0.04), other feeds (OR, 8.82; 95% CI, 1.74-44.63; p = 0.009), and suckling status (OR, 0.38; 95% CI, 0.15-0.99; p = 0.05) were significantly associated with T. parva infection in the multivariable mixed logistic model. Conclusion: T. parva is circulating in young calves in the study area (and possibly in cattle populations due to maternal transfer of antibodies to the calves). There is a need for molecular surveillance to determine the presence and burden of T. parva infection.

Evaluation of Petrifilms(TM) as a diagnostic test to detect bovine mastitis organisms in Kenya.

The study purpose was to validate Petrifilms(TM) (3M Microbiology, 2005) against standard culture methods in the diagnosis of bovine mastitis organisms in Kenya. On 128 smallholder dairy cattle farms in Kenya, between June 21, 2010 and August 31, 2010, milk samples from 269 cows that were positive on California Mastitis Test (CMT) were cultured using standard laboratory culture methods and Petrifilms(TM) (Aerobic Count and Coliform Count -3M Microbiology, 2005), and results were compared. Staphylococcus aureus was the most common bacterium isolated (73 % of samples). Clinical mastitis was found in only three cows, and there were only two Gram-negative isolates, making it impossible to examine the agreement between the two tests for Gram-negative- or clinical mastitis samples. The observed agreement between the standard culture and Petrifilm(TM) (3M Microbiology, 2005) results for Gram-positive isolates was 85 %, and there was fair agreement beyond that expected due to chance alone, with a kappa (κ) of 0.38. Using culture results as a gold standard, the Petrifilms(TM) had a sensitivity of 90 % for Gram-positive samples and specificity of 51 %. With 87 % of CMT-positive samples resulting in Gram-positive pathogens cultured, there was a positive predictive value of 93 % and a negative predictive value of 43 %. Petrifilms(TM) should be considered for culture of mastitis organisms in developing countries, especially when Gram-positive bacteria are expected.

Evaluation of antibody and antigen cross-reaction in Kenyan dairy cattle naturally infected with two pestiviruses: Bovine viral diarrhea virus and classical swine fever virus.

Background and Aim: Bovine viral diarrhea virus (BVDV) and classical swine fever virus (CSFV) are important pathogens of cattle and pigs, respectively, and belong to the genus Pestivirus. As CSFV has been shown to infect cattle, it can create diagnostic challenges of BVDV results through possible cross-reactivity where cattle could be exposed to pigs and CSFV. This study aimed to determine the possible cross-reactivity of BVDV and CSFV enzyme-linked immunosorbent assay (ELISA) results for antigen (Ag) and antibody (Ab) among smallholder dairy cattle in Kenya. Materials and Methods: This was a cross-sectional study based on a single visit to farms to collect serum samples and other descriptive farm-level and animal-level information. Testing for BVDV Ag and Ab was conducted on serum samples from 320 dairy cows and heifers, with CSFV Ag and Ab testing conducted on a subset of 133 and 74 serum samples, respectively. CSFV testing was based on BVDV test results and the availability of enough sample volume from farms that kept pigs. The Ag and Ab tests utilized IDEXX ELISA for both BVDV and CSFV. Results: For the 74 samples with Ab tests for both viruses, 40 (54.0%) were BVDV Ab positive, while 63 (85.1%) were CSFV Ab positive. Of the 40 BVDV Ab positive samples, 36 cattle (90.0%) tested positive for CSFV Ab. However, of the 34 BVDV Ab negative samples, 27 (79.4%) were CSFV Ab test-positive. For the 133 samples with Ag tests for both viruses, 125 (94.0%) were BVDV Ag positive, while 2 (1.5%) samples were CSFV Ag positive. None of the eight BVDV Ag negative samples was positive for CSFV Ag and only two (1.6%) of the 125 BVDV Ag positive samples were positive for CSFV Ag. Conclusion: The results indicate either substantial cross-reactivity of the two Ab ELISA tests, or reactivity with some other protein in the samples that led to the positive Ab test results. There was only limited evidence for cross-reactivity of the two Ag ELISA tests. We recommend that Pestivirus genus cross-reactivity be considered when interpreting BVDV ELISA results in cattle, more for Ab than Ag tests. Further research is needed to clarify the levels of cross-reactivity between BVDV and other Pestivirus Ag and Ab tests from animals on mixed-species farms.

Factors associated with total coliform and total viable bacterial count in camel milk from Isiolo County, Kenya.

Background and Aim: Camels have adaptive features to harsh climatic conditions, which make them a valued stable source of livelihood in arid lands. This study estimated the total bacterial and coliform counts (CCs), their associated factors in raw camel milk from the pastoral camel keepers, and the entire milk value chain in Isiolo County and Nairobi, Kenya. This study elucidates the bacterial load in camel milk and its potential risk. Moreover, this study provides recommendations on how to avert a human health hazard. Materials and Methods: This cross-sectional study targeted the camel pastoralists in Isiolo County, in the northern central part of Kenya. The study was conducted in July and August 2021. In addition, camel milk samples were collected along the value chain key points, including the producers, transporters, one bulker, and small traders in Isiolo town, and other retailers in Nairobi City. Eight camel herds were purposively selected and visited for a sample collection from pooled milking containers (10 mL each). In addition, milk was collected from pooled milk through the transporters, two milk bulkers, and several milk retailers in Isiolo town. Milk was further collected from retailers in Eastleigh town, Nairobi City. At each sampling point, 20 mL of milk sample was collected aseptically. The milk samples were assessed for total viable bacterial counts (TVBC) and CCs using the plate count and digital colony count, respectively. Results: A total of 76 respondents were selected and 213 milk samples were collected in this study. The respondents included the 1 (1.3%) bulker, 32 (42.1%) producers, 26 (34.2%) traders, and 17 (22.4%) transporters. Most respondents were male (62%), with most being over 40 years old. Overall, the TVBC had a mean of 2436835 ± 9276636 and a median of 3600. Furthermore, the multivariable multilevel mixed-effects linear regression model indicated that gender and practice of smoking milk-handling containers were positively and negatively associated with high counts of the natural logarithm of total viable bacteria, respectively. Of the milk samples evaluated for the CC, 10.3% (22/213) had counts greater than or equal to (≥) 100,000, where some also indicated extreme outliers of about 9.3 million. Conclusion: This study reports a low proportion of camel milk samples with high total viable bacterial and CCs. The material of the milk container and level of education interactively affected the total viable bacteria.

The prevalence, antimicrobial sensitivity, and factors associated with camel mastitis in Isiolo County, Kenya.

Background and Aim: The one-humped camels (Camelus dromedarius) adapt very well to arid and semi-arid (ASALs) environments and continue to thrive and produce milk even during severe droughts when cattle, sheep, and goats experience high mortalities. These attributes make the dromedaries very vital for the survival of pastoralists, especially in the ASALs of Africa. Mastitis is among the most important diseases of camels and can cause significant economic losses, thereby endangering the livelihoods of pastoralists. This study aimed to estimate the prevalence, risk factors, and antimicrobial sensitivity of mastitis-causing pathogens in lactating camels in Isiolo County, Kenya. Materials and Methods: This was a cross-sectional study conducted in July and August 2021. A questionnaire was administered to the camel keepers to capture data on herd-level factors. Lactating camels were then examined for any visible signs of clinical mastitis and as well as to capture data on other animal-level factors such as age, weight, and body condition score. A composite milk sample was collected aseptically from randomly selected camels in a herd. The samples were initially tested for somatic cell counts (SCC) using Somatos mini® automatic cell counter. Culture and sensitivity testing was then carried out on any milk sample that had SCC ≥ 200,000 cells/mL. The descriptive analysis was initially used to summarize the continuous and categorical farm and camel factors, while mixed regression models were used to explore the association between/across mastitis and the farm as well as camel-level factors. Results: A total of 210 lactating camels from 23 herds were selected and sampled in this study. The average age of camel keepers was 48.3 ± 16.3 years and they were involved in rearing camels for a mean of about 14.3 ± 8.6 years. The total number of camels in a herd ranged from 10 to 287, with the mean total herd milk production being 34.5 ± 24.9 L/day. The mean daily milk production per camel was 2.8 ± 1.7 L while the range for days in milk was between 21 and 787 days. The average age of camel first calving and the inter-calving interval was 56.3 ± 9.9 and 27.7 ± 9.9 months, respectively. The median parity of the dam was three and the body condition score was two. About 39.7% (83/210) of the sampled camels had clinical mastitis during the current lactation. The overall prevalence of mastitis (SCC ≥ 200,000 cells/mL) in camels was 17.6%. The main pathogens isolated were Streptococcus and Staphylococcus bacteria. Streptococcus isolates were mainly sensitive to ampicillin and resistant to cefaclor. All 18 Staphylococcus isolates were sensitive to tetracycline, while 12/18 isolates were resistant to ampicillin. The factors that were significantly associated with mastitis were the age of the respondent (p = 0.038), the number of years involved in camel rearing (p = 0.024), presence of clinical mastitis since calving (p = 0.039), body condition score (p = 0.040), and age of the dam at the time of examination (p = 0.072). Conclusion: Results from this study revealed that mastitis is an important condition among camels in the pastoral communities of Isiolo County, Kenya. Thus, pastoralists should continue to be aware of and trained on mastitis occurrence and its control in the pastoral ecosystem to reduce potential economic losses.

Effectiveness of dry cow therapy and/or internal teat sealant on existing infections in smallholder dairy farms in Kenya.

BACKGROUND AND AIM: Dry cow therapy (DCT) can be an effective treatment of mastitis that has not responded to conventional treatment during lactation. The aim of this study was to establish the effectiveness of DCT options available in reducing intramammary infections in smallholder dairy farms in Kiambu County, Kenya. MATERIALS AND METHODS: The study targeted smallholder dairy farms which were registered at the local dairy cooperatives and which had cows that were at the point of dry-off. A total of 32 cows with 121 quarters that were California Mastitis Test (CMT) positive were recruited, with the quarters randomly allocated to receive either DCT (DCT - neomycin sulfate, penethamate hydriodide, and procaine benzylpenicillin) and internal teat sealant (ITS) or ITS alone (bismuth nitrate) after aseptically collecting quarter milk samples for bacterial culture. Farm- and animal-level factors were captured through a questionnaire which was administered to the principal farmer or a person who was managing the animals. Post-calving, milk samples were also collected for bacterial culture to establish if the infection was cleared or if there was a new infection. RESULTS: DCT with ITS significantly reduced the proportion of quarters infected with Staphylococcus aureus from 64.0% at dry-off to 44.0% post-calving (35% reduction). In the control group, ITS alone, there was a small reduction in proportions of S. aureus from 46.8% to 40.4%. Proportions of quarter infections by coagulase-negative Staphylococcus in the treatment group reduced from 16.0% at dry-off to 2.0% post-calving, with a significant reduction in the control group too from 19.1% to 4.3%, which could be due to self-cure. Actinomyces species, Escherichia coli, Streptococcus species, and Pseudomonas species proportions slightly increased in the treatment group, as did E. coli and Pseudomonas species proportions in the control group. CONCLUSION: In smallholder dairy farms with subclinical mastitis, DCT of CMT-positive cows leads to a significant decrease of S. aureus infections at calving.

Causes of calf mortality in peri-urban area of Nairobi, Kenya.

The study reported data from 507 post-mortem records in the Department of Pathology, Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Nairobi, Kenya. The records were from carcasses obtained from the peri-urban area of Nairobi during a 20-year period between 1990 and 2009. Approximately 80% (393/507) of the calf carcasses had their diagnosis made through post-mortem examination, while the rest (114/507) were inconclusive. Just less than half (48.3%) of the calf carcasses presented had their age specified by the owners compared to 51.7% whose age was not specified. For calf carcasses whose age was specified by the owners, those indicated as more than 3 months were one-and-a-half times as many as those below 3 months old. The proportion of female carcasses (53.8%, 273/507) presented for post-mortem were slightly higher than the male carcasses (46.2%, 234/507). Diseases or conditions of the respiratory system were the most common 17.7% (97/507) while gastrointestinal tract (GIT) was second and affected 16.1% (88/507) of the cases. Another small number, 3.3% (18/507), died from bloat giving the total cases associated with GIT as 19.4% (106/507). Severe calf malnutrition and septicaemia were the third most reported causes of calf mortality in similar proportions at 14.3% (78/507) and 14.4% (79/507), respectively. Other minor causes of calf mortality were tick-borne diseases 8.6% (47/507), helminthiasis and poisoning, 2.9% (16/507) and 1.8% (10/507), respectively.

Sero-prevalence and risk factors of infectious bovine rhinotracheitis virus (type 1) in Meru County, Kenya.

The aim of the study was to determine the antibody sero-prevalence of Bovine Herpesvirus-1 which cause Infectious Bovine Rhinotracheitis (IBR) and to identify risk factors associated with BHV-1 antibody seropositivity among smallholder dairy farms in Meru County, Kenya. A cross-sectional study was conducted in the Naari area of Meru County, Kenya between September-October 2016 and March-April 2017. The 149 farmers were randomly selected from members of the Naari Dairy Farmers Cooperative Society who were actively delivering milk to the society at the time of the study. Serum samples were obtained from 403 female dairy cattle. Farm level management and animal factors were collected through direct interviews with the owner or someone who was knowledgeable about the animals. All serum samples were processed with an indirect enzyme-linked immunosorbent assay (gB ELISA) to determine the presence of antibodies to BHV-1. The overall farm-level and animal-level sero-prevalences of BHV-1 antibodies were 30.9 % (95 % CI: 23.6%-39.0%) and 17.4 % (95 % CI: 13.8%-21.4%), respectively. In the final multivariable analysis, the factors significantly associated with BHV-1 antibodies included; age of the dairy cattle (OR = 1.200, p = 0.001), age of the principal female farmers (OR = 0.182, p = 0.001) and rearing goats in the farm (OR = 26.77, p = 0.000). There was a significant interaction between rearing goats on the farm and age of the dairy cattle (p < 0.010); younger cattle seemed to have been exposed to BHV or a cross-reacting caprine herpesvirus when goats were on the farm. The results showed that BHV-1 was circulating among the cattle population in the Naari area of Meru County. Given that there is not BHV-1 vaccination use in this study population, training on the importance of biosecurity and vaccination for BHV-1 are recommended to reduce the transmission and impacts of BHV-1.

Assessment of farmers' compliance in implementing recommended cow comfort changes and their effects on lying time, stall and cow cleanliness within smallholder dairy farms in Kenya.

Our study aimed to evaluate farmers' compliance in implementing recommendations of farm-specific cow comfort changes, and the effects of these changes on lying time, stall cleanliness and cow cleanliness using a randomized controlled trial carried out on 100 smallholder dairy farms in Kenya, with 62 and 11 farms remaining in the intervention and control groups, respectively. On the first farm visit, data loggers were attached on lactating cows to determine lying time and questionnaires utilized to collect baseline data. Three days later, stall design and management recommendations were given to the intervention group of farmers orally and in written form. After an average of 39 ±â€¯7 days, data loggers were re-attached, compliance was assessed, and a post-intervention questionnaire was administered to the intervention group on the third visit. Three days subsequent to the first and third visits, data loggers were removed from all cows. Data were analysed in Stata 14.2® using proportion tests and Kruskal-Wallis rank tests to compare cleanliness scores and lying time, respectively. Interaction effects between treatment groups and visits were assessed using multivariable mixed linear and logistic regression models. While 46 of the 62 intervention farmers (74%) made at least one recommended change to cow comfort, 63% of the 324 overall recommendations were implemented. The odds of a recommendation being implemented were significantly higher when:1) major recommendations were given relative to minor recommendations (OR = 6.28); 2) recommendations were related to floor characteristics (floor softness and flatness) in comparison to recommendations related to stall design (OR = 3.14). The odds of compliance were lower on: 1) farms where the farm-hands received the recommendations compared to farms that had the female principal farmer receive the recommendations (OR = 0.01); 2) farms that had recommended changes related to roof, alley and sharps fixes relative to stall design fixes (OR = 0.13). Post-intervention, stall, udder and upper hind-leg cleanliness scores improved significantly (p < 0.0001, p = 0.021 and p = 0.017, respectively) in the intervention farms but not in the control farms. There was no significant difference in lying times between intervention and control farms, with 0.6 and 0.2 h/day increases being recorded in the intervention and control groups, from the 10.9 and 10.4 h/day at baseline, respectively. Giving farm-specific cow comfort recommendations to smallholder dairy farmers in Kenya, and providing them with a participatory role in the formulation and implementation of improvement recommendations ensured good acceptance and a high degree of implementation, and led to a subsequent improvement in cow comfort and cleanliness.

Knowledge and practices regarding Middle East Respiratory Syndrome Coronavirus among camel handlers in a Slaughterhouse, Kenya, 2015.

Dromedary camels are implicated as reservoirs for the zoonotic transmission of Middle East Respiratory Syndrome coronavirus (MERS-CoV) with the respiratory route thought to be the main mode of transmission. Knowledge and practices regarding MERS among herders, traders and slaughterhouse workers were assessed at Athi-River slaughterhouse, Kenya. Questionnaires were administered, and a check list was used to collect information on hygiene practices among slaughterhouse workers. Of 22 persons, all washed hands after handling camels, 82% wore gumboots, and 65% wore overalls/dustcoats. None of the workers wore gloves or facemasks during slaughter processes. Fourteen percent reported drinking raw camel milk; 90% were aware of zoonotic diseases with most reporting common ways of transmission as: eating improperly cooked meat (90%), drinking raw milk (68%) and slaughter processes (50%). Sixteen (73%) were unaware of MERS-CoV. Use of personal protective clothing to prevent direct contact with discharges and aerosols was lacking. Although few people working with camels were interviewed, those met at this centralized slaughterhouse lacked knowledge about MERS-CoV but were aware of zoonotic diseases and their transmission. These findings highlight need to disseminate information about MERS-CoV and enhance hygiene and biosafety practices among camel slaughterhouse workers to reduce opportunities for potential virus transmission.

A cross-sectional study of the welfare of calves raised in smallholder dairy farms in Meru, Kenya, 2017.

AIM: This study was aimed at describing calf comfort and determining the individual and pen level factors that affect comfort status (in particular, calf leg hygiene scores) of smallholder dairy farms in Meru County, Kenya. MATERIALS AND METHODS: A cross-sectional study was carried out on 52 calves that were up to 1 year old in 38 dairy farms (mean±standard deviation: Herd size=1.71±0.7 milking cows and milk production=6.7±3.1 L/day) in Meru, Kenya, in 2017, with the intention to describe their comfort and determine the factors associated with leg hygiene as a critical parameter for calf comfort assessment. Calves' biodata, health status, and leg hygiene were assessed, along with pen characteristics such as area, hygiene, and knee impact and knee wetness scores, while a questionnaire was administered to the farmers to gather information regarding calf housing management practices in the farm. RESULTS: The calves had a mean body weight of 85.2±32.8 kg and average daily weight gain of 0.50±0.45 kg per day. 71% of calves had a good body condition score (≥2.5), and the mean space allowance per calf was 2.52±1.56 m2. Approximately 75% of the calves (39/52) were kept in pens, and the rest were reared outdoors. For 39 calves kept indoors, 26% (10/39) of them had wooden or concrete floors while 74% (29/39) had dirt floors. Nearly two-thirds (62%) of indoor calves (26/39) were reared in pens with bedding, and 23% (9/39) and 33% (13/39) of the calves reared indoors were kept in pens displaying a failed knee impact test and failed knee wetness test. Indoor housed calves had an increased probability of having dirty calf legs (cleanliness score of >2.5) by 8.6 times (p=0.031), compared to outdoor-housed calves. In the final multivariable logistic regression model of 39 calves in pens, concrete or wood floors (odds ratio [OR]=7.9, p=0.047), poor body condition (OR=17.1, p=0.020) and use of bedding (OR=12.5, p=0.046) appeared to be positively correlated with dirtiness of calf legs, compared to dirt floors, good body condition, and no bedding, respectively. CONCLUSION: Overall, some calf comfort aspects were covered for the majority of calves examined, but 69% of the pens were categorized as dirty, especially those with wooden or concrete floors and poor bedding management. Smallholder dairy farmers in Kenya should be trained on calf housing management to improve calf comfort and productivity.

Randomized controlled trial on impacts of dairy meal feeding interventions on early lactation milk production in smallholder dairy farms of Central Kenya.

There is limited field-based research and recommendations on the effect of cattle feeding management practices on smallholder dairy farms (SDF) for the growing dairy industry in Kenya. This controlled trial aimed to determine the effect of feeding locally produced dairy meal (DM) on early lactation daily milk production (DMP) on Kenyan SDF, controlling for other factors associated with DMP. Privately owned, recently calved cows (n=111) were randomly assigned to one of three groups of feeding recommendations for DM (meeting predicted DM requirements by: (1) 100%; (2) 50%; or (3) feeding by the farmer's discretion). DM was provided for free to groups 1 and 2 to ensure they had sufficient DM to feed to the recommendations. Data collection on cow and farm characteristics occurred biweekly for a 60-day period post-calving starting in June 2013. A repeated measures multivariable linear regression model was used on the DMP outcome variable. With variability in DM consumption within feeding groups due to variability in DMP, actual DM fed was assessed as an independent variable rather than assigned feeding groups. DMP was positively associated with each kg/day of DM fed (0.53kg/day), cow weight (0.13kg/day), feeding DM in the month prior to calving (1.42kg/day), and feeding high protein forage (0.41kg/day), and was negatively associated with having mastitis (-0.30kg/day). In interaction terms, taller cows had higher DMP than shorter cows, whereas heifers (first parity cows) had similar DMP regardless of height. Also, thin cows (2+ parity with body condition score<2.5 out of 5) produced less milk (1.0kg/day less) than cows with a better body condition score at calving,whereas thin heifers produced more milk (2.0kg/day more) than heifers in better body condition-this association is possibly due to a small unrepresentative sample size of heifers. In conclusion, feeding DM in the month prior to calving, improving body condition in cows prior to calving, and enhancing dietary DM and high protein forage were positively associated with DMP in early lactation on Kenyan SDF. In addition there was an association between, taller cows and increased DMP, evidence supporting the importance of educating farmers on good genetic selection and heifer management. These findings will help with future management recommendations for higher DMP on SDF.

Risk factors associated with Cryptosporidia, Eimeria, and diarrhea in smallholder dairy farms in Mukurwe-ini Sub-County, Nyeri County, Kenya.

AIM: This study was undertaken to determine the household, calf management, and calf factors associated with the occurrence of Eimeria, Cryptosporidia, and diarrhea in pre-weaned calves reared in smallholder dairy farms in Mukurwe-ini Sub-County of Nyeri County, Kenya. In addition, the study also evaluated factors associated with average daily weight gain in the same pre-weaned calves. MATERIALS AND METHODS: A total of 112 newborn calves (63 males and 49 females) on 111 farms (1 set of twins) were followed for 2 months between June 2013 and August 2013. Two calves were lost to follow-up. A pre-tested questionnaire was used to collect data on household characteristics and calf management practices in the 111 selected farms. On the first visit to the farm (within 7 days of the birth of the calf), blood samples were collected from the jugular vein to assess the level of maternal immunity acquired by the calf, by determining the serum total protein and selenium concentration. At 4 and 6 weeks of age, fecal samples from the calves were collected to assess the presence of Cryptosporidia and Eimeria oocysts. Every 2 weeks for 2 months, the calves and their environments were examined, their 2-week consumption and health history were recorded, and weights were estimated with a weight tape. Each of the factors was evaluated in a univariable regression model and only those found to be significant (p≤0.20) were included in a multivariable model. Elimination of non-significant factors was done in the multivariable model through a backward elimination procedure so that only those variables which were confounders, and/or significant at (p≤0.05) remained in the final model. RESULTS: About 37% (41/110) of the calves experienced diarrhea at least once during the 2-month study period. The overall period prevalence of Eimeria and Cryptosporidia was 42.7% (47/110) and 13.6% (15/110), respectively. Low serum protein was associated with 1.8 and 2.4 times the odds of Eimeria and Cryptosporidia infections, respectively. Lack of supervision of calf birth and low serum total protein were both associated with 1.3 times the odds of diarrhea incidence. Dirty calf pens, feeding <5 L of milk/day, and infection with Eimeria were associated with 0.105, 0.087, and 0.059 kg, respectively, reduced average daily weight gain of the calves. CONCLUSION: In the Kenyan context, calf diarrhea risk could be reduced through better supervision of parturition and colostrum provision. Specifically, the risk of Eimeria and Cryptosporidia infections could be reduced by optimizing the passive transfer of immunity to the newborn calves. Average weight gains of calves could be improved by good colostrum provision, pen hygiene, and preventing Eimeria infections.

Associations of farm management practices with annual milk sales on smallholder dairy farms in Kenya.

AIM: Cows on smallholder dairy farms (SDF) in developing countries such as Kenya typically produce volumes of milk that are well below their genetic potential. An epidemiological study was conducted to determine reasons for this low milk production, including limited use of best management practices, such as suboptimal nutritional management. METHODS: An observational cross-sectional study of 111 SDF was performed in Nyeri County, Kenya in June of 2013 determining the effect of cow factors, farmer demographics and farm management practices on the volume of milk sold per cow per year (kg milk sold/cow). In particular, the effect of feeding high protein fodder trees and other nutritional management practices were examined. RESULTS: Approximatly 38% of farmers fed fodder trees, but such feeding was not associated with volume of milk sold per cow, likely due to the low number of fodder trees per farm. Volume of milk sold per cow was positively associated with feeding dairy meal during the month prior to calving, feeding purchased hay during the past year, deworming cows every 4 or more months (as opposed to more regularly), and having dairy farming as the main source of family income. Volume of milk sold per cow was negatively associated with a household size of >5 people and feeding Napier grass at >2 meters in height during the dry season. An interaction between gender of the principal farmer and feed shortages was noted; volume of milk sold per cow was lower when female farmers experienced feed shortages whereas milk sold per cow was unaffected when male farmers experienced feed shortages. CONCLUSIONS: These demographic and management risk factors should be considered by smallholder dairy farmers and their advisors when developing strategies to improve income from milk sales and animal-source food availability for the farming families.

Prevalence of Cryptosporidia, Eimeria, Giardia, and Strongyloides in pre-weaned calves on smallholder dairy farms in Mukurwe-ini district, Kenya.

AIM: Gastrointestinal diseases are among the leading causes of calf morbidity and mortality in Kenya and elsewhere. This study was undertaken to determine the prevalence of Cryptosporidia, Eimeria, Giardia, and Strongyloides in calves on smallholder dairy farms (SDF) in Mukurwe-ini District, Nyeri County, Kenya. These infections have been associated with economic losses by decreased growth rates, decreased productivity, and increased susceptibility to other diseases. MATERIALS AND METHODS: An observational study was conducted on 109 farms in Mukurwe-ini District, Nyeri County, Kenya, where 220 calf fecal samples (each calf at 4 and 6 weeks of age) from 110 calves (1 set of twins) were collected and analyzed for Cryptosporidia, Eimeria, Giardia, and helminth parasites. RESULTS: Eimeria oocysts, Cryptosporidia oocysts, and Strongyloides eggs were detected in the fecal samples examined, but no Giardia cysts were found. The overall period prevalence of Eimeria, Cryptosporidia, and Strongyloides was 42.7% (47/110), 13.6% (15/110), and 5.4% (6/110), respectively. The prevalence at 4 weeks of age for Eimeria, Cryptosporidia, and Strongyloides was 30.0% (33/110), 8.2% (9/110), and 3.7% (4/109), respectively, while the prevalence at 6 weeks of age was 20.2% (22/109), 6.5% (7/107), and 2.7% (3/110), respectively. There was, however, no significant difference in the prevalence at 4 and 6 weeks (p>0.05). CONCLUSION: Findings from this study show that Eimeria, Cryptosporidia, and Strongyloides, are prevalent in the study area and indicate the need to adopt optimal management practices to control infections in calves.

Mastitogenic bacteria isolated from dairy cows in Kenya and their antimicrobial sensitivity.

There is limited epidemiological knowledge on udder health in Kenyan dairy cattle that would aid in a pro-active approach towards mastitis prevention. The study objectives were: (1) to investigate the prevalence and distribution of clinical and subclinical mastitis in dairy cattle in Mukurwe-ini and Nakuru Districts, Kenya, and (2) to determine the antibacterial sensitivity of the organisms causing bovine mastitis in these districts. The study involved field-screening of milk samples from 241 dairy cows on 128 farms by use of the California Mastitis Test (CMT) and, if CMT-positive, followed by bacteriological culture of the major causative agents and their respective antibiotic sensitivity to eight commonly used antibiotics. All participating farms were visited twice during the study period. The results obtained during the first and second visits showed the prevalence of clinical mastitis to be very low: 0.9% and 0.5%, respectively; 56.0% and 65.0% of cows were CMT-positive on at least one quarter and 49.6% and 58.7% of cows were culture-positive, respectively. There was no significant difference in mastitis prevalence between Nakuru and Mukurwe-ini districts (p > 0.10). Staphylococcus aureus was isolated in 68.0% and 77.0% of samples during the first and second visits, respectively. Other frequently isolated agents included Streptococcus agalactiae, and other Streptococcus spp., S. aureus and S. agalactiae were most sensitive to gentamycin and norfloxacin, and least sensitive to cotrimazole and ampicillin. Knowing the prevalence of mastitogenic organisms and their antibiotic sensitivities could improve treatment efficacy and cow longevity.

Willingness to pay for contagious bovine pleuropneumonia vaccination in Narok South District of Kenya.

Contagious bovine pleuropneumonia (CBPP) is an economically important trans-boundary cattle disease which affects food security and livelihoods. A conjoint analysis-contingent valuation was carried out on 190 households in Narok South District of Kenya to measure willingness to pay (WTP) and demand for CBPP vaccine and vaccination as well as factors affecting WTP. The mean WTP was calculated at Kenya Shillings (KSh) 212.48 (USD 3.03) for vaccination using a vaccine with the characteristics that were preferred by the farmers (preferred vaccine and vaccination) and KSh -71.45 (USD -1.02) for the currently used vaccine and vaccination. The proportion of farmers willing to pay an amount greater than zero was 66.7% and 34.4% for the preferred and current vaccine and vaccination respectively. About one third (33.3%) of farmers would need to be compensated an average amount of KSh 1162.62 (USD 13.68) per animal to allow their cattle to be vaccinated against CBPP using the preferred vaccine and vaccination. About two-thirds (65.6%) of farmers would need to be compensated an average amount of KSh 853.72 (USD 12.20) per animal to allow their cattle to be vaccinated against CBPP using the current vaccine and vaccination. The total amount of compensation would be KSh 61.39 million (USD 0.88 million) for the preferred vaccine and vaccination and KSh 90.15 million (USD 1.29 million) for the current vaccine and vaccination. Demand curves drawn from individual WTP demonstrated that only 59% and 27% of cattle owners with a WTP greater than zero were willing to pay a benchmark cost of KSh 34.60 for the preferred and current vaccine respectively. WTP was negatively influenced by the attitude about household economic situation (p=0.0078), presence of cross breeds in the herd (p<0.0001) and years since CBPP had been experienced in the herd (p=0.0375). It was positively influenced by education (p=0.0251) and the practice of treating against CBPP (p=0.0432). The benefit cost ratio (BCR) for CBPP vaccination was 2.9-6.1 depending on the vaccination programme. In conclusion, although a proportion of farmers was willing to pay, participation levels may be lower than those required to interrupt transmission of CBPP. Households with characteristics that influence WTP negatively need persuasion to participate in CBPP vaccination. It is economically worthwhile to vaccinate against CBPP. A benefit cost analysis (BCA) using aggregated WTP as benefits can be used as an alternative method to the traditional BCA which uses avoided production losses (new revenue) and costs saved as benefits.

Exploring farmer preferences for contagious bovine pleuropneumonia vaccination: a case study of Narok District of Kenya.

Contagious bovine pleuropneumonia (CBPP) is an economically important disease in most of sub-Saharan Africa. A conjoint analysis and ordered probit regression models were used to measure the preferences of farmers for CBPP vaccine and vaccination attributes. This was with regard to inclusion or not of an indicator in the vaccine, vaccine safety, vaccine stability as well as frequency of vaccination, vaccine administration and the nature of vaccination. The analysis was carried out in 190 households in Narok District of Kenya between October and December 2006 using structured questionnaires, 16 attribute profiles and a five-point Likert scale. The factors affecting attribute valuation were shown through a two-way location interaction model. The study also demonstrated the relative importance (RI) of attributes and the compensation value of attribute levels. The attribute coefficient estimates showed that farmers prefer a vaccine that has an indicator, is 100% safe and is administered by the government (p<0.0001). The preferences for the vaccine attributes were consistent with expectations. Preferences for stability, frequency of vaccination and nature of vaccination differed amongst farmers (p>0.05). While inclusion of an indicator in the vaccine was the most important attribute (RI=43.6%), price was the least important (RI=0.5%). Of the 22 household factors considered, 15 affected attribute valuation. The compensation values for a change from non inclusion to inclusion of an indicator, 95-100% safety, 2h to greater than 2h stability and from compulsory to elective vaccination were positive while those for a change from annual to biannual vaccination and from government to private administration were negative. The study concluded that the farmers in Narok District had preferences for specific vaccine and vaccination attributes. These preferences were conditioned by various household characteristics and disease risk factors. On average the farmers would need to be compensated or persuaded to accept biannual and private vaccination against CBPP. There is need for consideration of farmer preferences for vaccine attribute levels during vaccine formulations and farmer preferences for vaccination attribute levels when designing delivery of vaccines.