First glimpse into the origin and spread of the Asian longhorned tick,Haemaphysalis longicornis,in the United States

Established populations of Asian longhorned ticks (ALT), Haemaphysalis longicornis, were first identified in the United States (US) in 2017 by sequencing the mitochondrial cytochrome c oxidase subunit I (cox1) ‘barcoding’ locus followed by morphological confirmation. Subsequent investigations detected ALT infestations in 12, mostly eastern, US states. To gain information on the origin and spread of US ALT, we (1) sequenced cox1 from ALT populations across 9 US states and (2) obtained cox1 sequences from potential source populations [China, Japan and Republic of Korea (ROK) as well as Australia, New Zealand and the Kingdom of Tonga (KOT)] both by sequencing and by downloading publicly available sequences in NCBI GenBank. Additionally, we conducted epidemiological investigations of properties near its initial detection locale in Hunterdon County, NJ, as well as a broader risk analysis for importation of ectoparasites into the area. In eastern Asian populations (China/Japan/ROK), we detected 35 cox1 haplotypes that neatly clustered into two clades with known bisexual versus parthenogenetic phenotypes. In Australia/New Zealand/KOT, we detected 10 cox1 haplotypes all falling within the parthenogenetic cluster. In the United States, we detected three differentially distributed cox1 haplotypes from the parthenogenetic cluster, supporting phenotypic evidence that US ALT are parthenogenetic. While none of the source populations examined had all three US cox1 haplotypes, a phylogeographic network analysis supports a northeast Asian source for the US populations. Within the United States, epidemiological investigations indicate ALT can be moved long distances by human transport of animals, such as horses and dogs, with smaller scale movements on wildlife. These results have relevant implications for efforts aimed at minimizing the spread of ALT in the United States and preventing additional exotic tick introductions.     

Reproducibility of an objective four‐choice canine vision testing technique that assesses vision at differing light intensities

Objective The increasing importance of canine retinal dystrophy models means accurate vision testing is needed. This study was performed to evaluate a four‐choice vision testing technique for any difference in outcome measures with repeated evaluations of the same dogs. Animals studied Four 11‐month‐old RPE65‐deficient dogs. Procedures Vision was evaluated using a previously described four‐choice vision testing device. Four evaluations were performed at 2‐week intervals. Vision was assessed at six different white light intensities (bright through dim), and each eye was evaluated separately. The ability to select the one of the four exit tunnels that was open at the far end was assessed (‘choice of exit’) and recorded as correct or incorrect first tunnel choice. ‘Time to exit’ the device was also recorded. Both outcomes were analyzed for significance using anova . We hypothesized that performance would improve with repeated testing (more correct choices and more rapid time to exit). Results ‘Choice of exit’ did not vary significantly between each evaluation (P = 0.12), in contrast ‘time to exit’ increased significantly (P = 0.012), and showed greater variability in dim light conditions. Conclusions We found no evidence to support the hypothesis that either measure of outcome worsened with repeated testing; in fact, the ‘time to exit’ outcome worsened rather than improved. The ‘choice of exit’ gave consistent results between trials. These outcome data indicate the importance of including a choice‐based assessment of vision in addition to measurement of device transit time.     

Factors influencing choice of veterinary service provider by pastoralist in Kenya

This study analyzed the determinants for choice of animal health providers in a semiarid pastoral area with an aim of identifying specific attributes that could be targeted for intervention to enhance pastoralist access to quality veterinary services. The data were collected through administration of semi-structured questionnaires to 350 randomly selected household heads in different locations in Narok County of Kenya. Most of these respondents had no formal education (66.9 %), and most households were headed by men (88.9 %). The men were in control of sales (84.2 %), purchases (83.7 %), and treatment of sick cattle (70.3 %), while women were responsible for milking (83.8 %). Animal health services were delivered by drug stockists (87.76 %) and government veterinarians (12.24 %). The time spent while seeking animal health services and transport cost were specific attributes with impact on the probability of choice for service providers. Although distance covered to the preferred service provider was a significant attribute, it was inversely related to the probability of choice. The other factors including herd sizes, age and sex of household head, cost incurred per visit, level of education of household head, and the number of visits did not have significant impact on choices. These findings support commercialization of veterinary services in marginalized areas where the delivery of essential animal health services such as disease control programs are often viewed as a public good. In order to enhance delivery of veterinary services in these areas, it is proposed that public and private means are investigated to support qualified veterinarians and to strengthen the activities of untrained personnel operating drug outlets.     

Productivity in different cattle production systems in Kenya

Cattle are kept as an important source of livelihood in many Kenyan farming households whilst also having cultural and social value. A review was undertaken to estimate productivity in the three main Kenyan cattle production systems: small-scale dairy and meat; small-scale dairy; and large-scale dairy and meat. Data on production parameters were collected through a systematic literature search of electronic databases for peer reviewed and grey literature. The parameters included were reproductive rates, mortality rates and yields. Prices for livestock and livestock products were estimated from markets. The data were used to estimate net output from cattle using the Livestock Productivity Efficiency Calculator (LPEC), a deterministic steady state model which measures productivity as net output per megajoule (MJ) of metabolisable energy (ME). The estimated net outputs per livestock unit year^?1 were USD 146.6, USD 215.1 and USD 84.8 in the large-scale dairy and meat, small-scale dairy and meat and small-scale dairy systems, respectively. Milk production contributed significantly to net output in all systems and was 91.8 % of total output in small-scale dairy. Cattle sales had the highest contribution to net output in large-scale dairy and meat system (45.1 %). Sensitivity analysis indicated that output was most affected by milk yield, age and weight at maturity and parturition rate. The productivity differences between the production systems call for more detailed research on the constraints to the production systems such as diseases, and to describe the benefits that farmers and society would obtain from disease control and improved management.     

Milk production performance of Friesian-Holstein cows fed diets containing Medicago sativa, Centrosema pubescens, or groundnut haulms (Arachis hypogaea)

To investigate the effect of feeding dairy cows diets containing lucerne hay, centrosema hay, and groundnut haulms (crop residue) on dry matter intake (DMI), milk yield, and milk composition, nine multiparous Friesian-Holstein cows in their mid-lactation stage were used in a 3?×?3 crossover design replicated three times. Dairy cows fed lucerne hay had significantly (p?<?0.001) higher DMI than dairy cows fed centrosema hay. DMI for cows fed groundnut haulms and lucerne hay was not significantly different. Daily milk yield for dairy cows fed diet containing lucerne hay was significantly (p?<?0.01) higher than that for dairy cows fed diets containing groundnut haulms or centrosema hay. Milk composition and body condition scores of the cows were not significantly affected by either lucerne hay, groundnut haulms, or centrosema hay. Overall, the results in this study indicated that feeding dairy cows diets containing lucerne hay increased milk yield.