Prevalence of ticks and tick-borne diseases in cattle on communal rangelands in the Highland Areas of the Eastern Cape Province, South Africa

Surveys were conducted to compare the seasonal tick prevalence and loads, and sero-prevalence of tick-borne diseases (TBD) in Nguni and non-descript cattle on the sweet and sour communal rangelands of the Eastern Cape Province. The tick species observed on both rangeland types were Rhipicephalus appendiculatus (71.0 %), Rhipicephalus (Boophilus) species (29.2 %) and Rhipicephalus evertsi evertsi (40.2 %). Hyalomma species (19.0 %) occurred only on the sour rangeland. Tick loads were higher (P < 0.05) in the hot-wet season than in the cool-dry season. Cattle in the sweet rangeland had significantly lower (P < 0.05) tick loads than those in the sour rangeland. Rhipicephalus appendiculatus loads were lower (P < 0.05) in the indigenous Nguni than non-descript cattle in the hot-wet and post-rainy season. Hyalomma species were also significantly lower (P < 0.05) in the Nguni than non-descript cattle in all the seasons. Three TBDs were observed, namely Babesia bovis (44.6 %), Babesia bigemina (45.9 %) and Anaplasma marginale (25.6 %). All the animals were sero-negative for Ehrlichia ruminantium. Nguni cattle had lower (P < 0.05) sero-prevalence for A. marginale in the cool-dry season and B. bigemina in the cool-dry and hot-wet seasons. Cattle in the sweet rangeland had significantly lower sero-prevalence of B. bovis and B. bigemina. Infection with B. bovis and A. marginale decreased (P < 0.05) the packed cell volume. Nguni cattle were recommended for use in the integrated control of ticks and TBD in the communal areas of South Africa as they were better able to cope with tick and TBD infestations than non-descript breeds

Mechanisms of resistance to Rhipicephalus ticks in Nguni cattle reared in the semiarid areas of South Africa.

Ph.D. University of KwaZulu-Natal, Pietermaritzburg 2013.Ticks and tick borne-diseases (TBD) are major challenges to cattle production among smallholder farmers in the semiarid areas of South Africa. Nguni cattle have been reported to be resistant to ticks and TBD, however, the mechanisms responsible for the trait are not fully understood. The broad objective of this study was to determine the mechanisms of resistance to ticks in Nguni cattle reared in the semiarid areas of South Africa. Tick infestation levels, body condition scores (BCS), packed cell volumes (PCV) and the molecular prevalence of A. marginale were determined in Nguni (n = 70) and local crossbred (n = 79) cattle reared in the semiarid areas of South Africa. Relationships among skin thickness, hair length, coat score and tick counts were assessed in seven to nine month old Nguni (n = 12) and Bonsmara (n = 12) heifers. As a follow up, cutaneous hypersensitivity responses to unfed larval extracts (ULE) of the ticks Rhipicephalus decoloratus and Rhipicephalus microplus were examined in heifers to determine host immunity to the ticks. Tick counts and inflammatory cell infiltrates in skin biopsies from feeding sites of adult R. microplus ticks in nine-month-old Nguni and Bonsmara heifers were also evaluated. The molecular prevalence of A. marginale was similar in the Nguni (47.7 %) and local crossbred (52.3 %) cattle. Nguni cattle suffered less severe losses from and were more vi resilient to A. marginale infection than local crossbreds. Nguni heifers had lower coat scores, hair length and tick counts than the Bonsmara heifers. The relationship between tick counts and coat score was positive and linear in the Nguni (y = 1.90x – 0.40) and quadratic in Bonsmara (y = -7.98x2 + 12.74x - 3.12) heifers. Bonsmara cattle showed a more intense immediate reaction and no delayed hypersensitivity reaction to ULE of Rhipicephalus ticks. Nguni heifers presented a less intense immediate reaction and a delayed hypersensitivity reaction at 72 h post inoculation with ULE of Rhipicephalus ticks. Reactions to R. decoloratus ULE produced a more intense skin response at all time intervals in both breeds than that of R. microplus. Parasitized sites in Nguni heifers had higher (P < 0.05) counts of basophils, mast and mononuclear cells than those in the Bonsmara heifers. Conversely, parasitized sites in Bonsmara heifers had higher (P < 0.05) neutrophil and eosinophil counts than those in the Nguni heifers. Tick count was negatively correlated (P < 0.05) with basophil and mast cell counts. There was a positive correlation between eosinophil counts and tick counts in both breeds, and between tick counts and mononuclear cell counts in the Bonsmara breed. It was concluded that smooth and short coats, delayed type hypersensitivity and cutaneous basophil and mast cell infiltrations are responsible for increased tick resistance in the indigenous Nguni cattle breed of South Africa

Body condition scores, fluke intensity, liver pathology, and carcass quality of different dairy cattle genotypes infected with Fasciola species at high throughput abattoirs in South Africa

Milk is an essential commodity whose demand far exceeds supply. However, dairy animal productivity is constantly hampered by parasitic diseases such as fasciolosis, affecting milk production. Despite the negative impact of liver fluke on milk production, there is little information on liver fluke infection and associated abattoir losses (body weight, condition score, liver pathology, and carcass quality) in culled dairy cattle. This study aimed to determine body condition scores, fluke intensity, liver pathology, and carcass quality of different cattle genotypes infected with Fasciola species at three commercial abattoirs. A longitudinal study was conducted from September 2019 to October 2020 to determine body condition score, liver fluke intensity, liver pathology in 3065 dairy cattle slaughtered in CA1, CA2, and CA3, of the Eastern Cape Province South Africa. Liver fluke intensity significantly increased with cattle age (P < 0.0001). Cattle ≥ 7 years old (59.93 ± 6.42) and those 4 to 6 years old (49.78 ± 9.98) had higher infection than those 2 to 3 years old (27.55 ± 13.68). The liver fluke infection was significantly (P < 0.001) the highest when sampling was conducted in summer, followed by autumn and winter, and least for spring. The differences in carcass weights or body condition scores decreased by 0.99 units (P < 0.0001) or 0.97 units (P < 0.0001) respectively. Therefore, this study suggests that fluke infection could be responsible for considerable economic and production losses mainly due to condemnation and weight loss in dairy cattle. This study recommended a combination of holistic and grazing management to control infection rates in dairy herds.The National Research Foundation (NRF).https://link.springer.com/journal/436hj2023Veterinary Tropical Disease

Chevon production and quality of Kalahari Red goats fed increasing levels of hempseed cake substituted for soybean meal

A 42-d study was conducted to evaluate the effects of replacing soybean meal with increasing levels of hempseed cake (HSC) in goat finishing diets on growth performance, carcass and chevon quality attributes. Thirty-five, 3-month-old Kalahari Red wethers (25 ± 1.5 kg initial body weight) were randomly allocated to one of five dietary treatments with seven animals per treatment. Wethers were fed maize-lucerne based finishing diets with inclusions of 0 (control), 25, 50, 75 and 100 g/kg DM of HSC replacing soybean meal as the main protein source. Diet had no effect (P > 0.05) on daily feed intake, average daily gain, final body weight and income-over-feed costs. Carcass and meat quality attributes were not influenced (P > 0.05) by HSC, except intramuscular fat, which increased linearly (P ≤ 0.05) with HSC inclusion levels. It was concluded that HSC could completely replace soybean meal in goat finishing diets without affecting chevon production and quality.The South African Research Chairs Initiative in Meat Science: Genomics to Nutriomics funded by the National Research Foundation (NRF) and Department of Science and Technology of South Africa.http://www.elsevier.com/locate/meatscihj2023Veterinary Tropical Disease

Acaricide resistance of Rhipicephalus decoloratus ticks collected from communal grazing cattle in South Africa

OBJECTIVES: This study aimed to determine acaricide resistance in Rhipicephalus decoloratus ticks collected from grazing cattle between November 2018 and May 2019 in Elundini, Senqu, and Walter Sisulu Local Municipalities in the northeastern region of the Eastern Cape Province. MATERIALS AND METHODS: A sample of 20–30 adult engorged female R. decoloratus ticks were collected from at least 10 randomly selected cattle (highly tick-infested) at each dip tank and placed into the labelled plastic collection bottles containing absorbent paper and with a perforated lid at a constant room temperature of ±28°C and >70% relative humidity until resistance testing commenced. The Shaw larval immersion test method was used to determine R. decoloratus larvae resistance to various acaricide concentration levels [amidines, organophosphate (OP), and synthetic pyrethroids (SPs)]. RESULTS: This study found that most ticks were susceptible to exposure to different acaricide field concentrations of amidines (49% at 250 ppm), OPs (33% and 47% at 300 ppm and 500 ppm, respectively), and SPs (44% and 23% at 150 ppm and 300 ppm, respectively). The resistance testing resultsshowed no resistance to amidines at any localities and no resistance to OP in the Senqu region. However, resistance development of the larvae to amines, OPs, and SPs was extensively observed in Senqu (18%, 6%, and 7%), Elundini (15%, 15%, and 17%), and Walter Sisulu (13%, 19%, and 9%) regions, respectively. CONCLUSION: The larvae’sresistance is a cause for worry. Hence, the continuous monitoring of tick resistance to commonly used acaricides will help mitigate widespread acaricidal resistance and sustain livestock productivity.National Research Foundation, South Africa (NRF).https://bdvets.orgVeterinary Tropical Disease

Comparison of three diagnostic methods to detect the occurrence of Fasciola species in communally grazed cattle in the North West Province, South Africa

DATA AVAILABILITY STATEMENT : The data presented in this study are available on request from the corresponding author.Fasciolosis causes significant economic losses in commercial cattle herds in South Africa, but its prevalence is unknown in most communal areas. A cross-sectional study was conducted with the aim of determining the occurrence of bovine fasciolosis using three different diagnostic methods in Moretele Local Municipality in Bojanala District, NorthWest Province. Faecal samples were collected from 277 cattle of different breeds, ages, sex and faecal condition scores and examined using the sedimentation technique, quantitative real-time polymerase chain reaction (qPCR) and faecal antigen enzyme-linked immunosorbent assay (coproELISA). All samples were negative for bovine fasciolosis using coproELISA. A total of 73 (26.4%) samples were positive using the qPCR, while 36 were positive using the sedimentation technique, with low faecal egg counts (1 to 20 eggs per gram). The qPCR detected the highest positivity (26.4%, 95% CI 21.3, 32.0) followed by the sedimentation test (13.0%; 95% CI 9.3, 17.5). Location, breed, sex, age and faecal consistency score were not associated with positive qPCR results (p > 0.05). There was also no significant agreement (kappa = 0.011, p = 0.843) between qPCR and the sedimentation technique for the detection of Fasciola spp. The qPCR appeared to be the most sensitive method for detection of Fasciola spp. Further studies are required on the characterisation of Fasciola spp. in communal cattle in South Africa.The National Research Foundation (NRF) of South Africa, the University of Pretoria (South Africa) postgraduate bursary and the University of Ibadan (Nigeria) Tertiary Education Trust Fund.https://www.mdpi.com/journal/pathogensam2023Production Animal StudiesVeterinary Tropical Disease

A genetic and immunological comparison of tick-resistance in beef cattle following artificial infestation with Rhipicephalus ticks

Host resistance to ticks can be explored as a possible approach of combating tick infestations to complement the existing unsustainable tick control methods. Thirty-six beef cattle animals were used, consisting of Angus, Brahman and Nguni breeds, with each breed contributing 12 animals. Half of the animals per breed were artificially challenged with Rhipicephalus microplus and the other half with R. decoloratus unfed larvae per animal. Skin biopsies and blood samples were collected pre-infestation and 12 h post-infestation from the feeding sites of visibly engorging ticks. The success rate of the ticks was high and had an influence even at the early time point. Increased lymphocytes and blood urea nitrogen levels as well as decreased levels of segmented neutrophils were observed in the Angus, which were the opposite of those in the Brahman and Nguni. The increase in cholesterol, which was highest in the Angus and lowest in the Nguni, may be due to altered protein metabolism. The expression profiles of genes TRAF6, TBP, LUM and B2M were significantly different among breeds. Five genes (CCR1, TLR5, TRAF6, TBP, BDA20) had increased or constant expression post-infestation, whereas the expression of CXCL8, IL-10 and TNF-α decreased or remained the same after tick challenge. Genes that showed variation are involved in discouraging long-term supply of blood meal to the tick and those associated with immune responses. The gene LUM is a potential biomarker for tick resistance in cattle. The response to infestation by the breeds was consistent across the tick species.The National Research Foundation (NRF) (Grant No. 94606). The operational costs were subsidized by Stellenbosch University and the Agricultural Research Council-Animal Production (ARC-API).http://link.springer.com/journal/104932021-03-07hj2020Veterinary Tropical Disease

In search of the Rhipicephalus (Boophilus) microplus in the western-central regions of the Eastern Cape Province, South Africa

The southern cattle tick, Rhipicephalus (Boophilus) microplus, is an economically important tick that parasitises cattle and is found on other host species if they graze with cattle. The R. (B.) microplus is a highly adapted tick species prevalent in tropical and subtropical regions of the world. In Africa, it has expanded its range and was reported to supersede the native tick, R. (B.) decoloratus. The objective of the study was to determine the distribution of R. (B.) microplus under different ecological zones in the western-central regions of Eastern Cape Province. Engorged adult blue ticks were collected monthly from 360 randomly selected cattle and free living ticks from six replicate drags of the vegetation over a period of 1 year at Bedford Dry Grassland (BDG), Kowie Thicket (KT) and Bhisho Thornveld (BT). A special attention was paid to the lower perineum, neck, dewlap and ventral body parts which are the preferred sites for blue ticks during sampling. In this study, 9 species of ticks which grouped under 5 genera were identified. The identified species of ticks were Amblyomma hebraeum, Haemaphysalis elliptica, Hyalomma rufipes, Ixodes pilosus, R. (B.) decoloratus, R. appendiculatus, R. evertsi evertsi, R. follis and R. simus. Only adult R. (B.) decoloratus (n = 8090) ticks were collected from cattle between April 2016 and March 2017. A total of 4382 females and 3708 males of R. (B.) decoloratus were recovered during the survey. Of the ticks (n = 2885) collected from the vegetation, R. (B.) decoloratus was the most abundant species with a relative prevalence of 58.16%, followed by R. appendiculatus (18.37%) and R. evertsi evertsi (16.90%). Least abundant ticks were H. rufipes (2.98%), A. hebraeum (2.46%), H. elliptica (0.38%), R. follis (0.34%), I. pilosus (0.24%) and R. simus (0.17%). The distribution of R. (B.) decoloratus ticks differ significantly (P < 0.05) among the vegetation types. Significantly more (P < 0.05) engorged R. (B.) decoloratus were collected in KT during summer season (1.39 ± 0.063 females and 1.30 ± 0.063 males) compared to other vegetation types. The R. (B.) decoloratus larvae were significantly higher (P < 0.05) in BT (20.56±1.154) and KT (18.50±1.154) vegetation types during the spring season. R. (B.) microplus was not found in the present study, signifying that it is not yet established in western-central regions of the Eastern Cape Province and as such, continuous monitoring would be advisable.The National Research Foundation (Grant number: 102941).http://www.elsevier.com/locate/ttbdis2020-04-01hj2019Production Animal Studie

Rotational grazing approaches reduces external and internal parasite loads in cattle

We tested whether holistic planned grazing (HPG) and four-camp grazing (FCG) rotational grazing approaches influence beef cattle parasites counts compared with continuous, season-long (SLG) grazing. We expected that parasite counts would increase linearly with increasing camp occupancy by cattle from 1 d (70-camp, HPG) to 21–28 d (four-camp, FCG) to 180 d (one-camp per season, SLG). Tick and faecal egg counts were observed across seasons on 30 steers raised on a private farm in Cedarville, South Africa. Tick species identified were Rhipicephalus evertsi evertsi, Rhipicephalus (Boophilus) decoloratus, Hyalomma spp. and Amblyomma hebreaum with respective prevalences of 32%, 29%, 20% and 19%. Unidentified roundworms had the highest faecal worm egg counts (81.2%) followed by Coccidia (16.4%), Nematodirus (1.2%) and strongyles (1.2%). Overall, prevalence and mean counts for ticks and faecal worm eggs were highest in the hot wet season, with the SLG having greater (P ≤ 0.05) values than either of the rotational approaches. However, increasing camp number and animal densities above four camps did not reduce (P > 0.05) parasite loads compared with HPG. Current results suggest that rotational grazing is a potential strategy to reduce livestock losses caused by high tick and worm loads in cattle, especially in the hot wet season.The South African Red Meat Research and Development Trust (IRMA REF 21544) and Cape Wools South Africa (IRMA REF 22491) through H-JH of Conservation South Africa. RM acknowledges the National Research Foundation for providing a bursary.http://www.tandfonline.com/loi/tarf202020-09-22hj2019Production Animal Studie

Sericea lespedeza (Lespedeza juncea var. sericea) for sustainable small ruminant production: feed, helminth suppressant and meat preservation capabilities

CITATION: Mahachi, L. N. et al. 2020. Sericea lespedeza (Lespedeza juncea var. sericea) for sustainable small ruminant production: Feed, helminth suppressant and meat preservation capabilities. Animal Feed Science and Technology, 270. doi:10.1016/j.anifeedsci.2020.114688The original publication is available at https://www.sciencedirect.com/journal/animal-feed-science-and-technologySmall ruminants significantly contribute towards livelihood, food and nutrition security for people living in semiarid low-to-middle-income countries. However, their productivity is largely constrained by feed shortages, prevalence of gastrointestinal nematodes (GIN) and postharvest meat losses. The current review explores the possibility of using sericea lespedeza (Lespedeza juncea var. sericea) as a natural helminth suppressant, feed ingredient and meat preservative for improving small ruminant health, meat production and shelf life. Sericea lespedeza has moderate contents of crude protein, fibre, minerals, vitamins, amino acids, and diverse composition of physiologically active substances such as condensed tannins, sterols and flavanols from which it derives nutritional, anti-bloat, helminth suppressant, antimicrobial and antioxidative properties. Overall, the present review demonstrates the potential of feeding sericea lespedeza to small ruminants as a sustainable means of controlling GIN and enhancing meat production and shelf life, while also reducing greenhouse gas (GHG) emissions. However, more research is required to determine optimal feeding strategies and doses for reducing GHG emissions while improving health, meat production and quality of small ruminants.https://www.sciencedirect.com/science/article/pii/S0377840120305927?via%3DihubPublishers versio