By Simon Ngena

IN the last few years, Zimbabwe has lost millions of cattle to the tick-borne disease, theileriosis, better known as January disease or, in some cases, ‘cattle Covid’.

It has caused significant losses in cattle populations in recent years, with over half a million deaths since 2016.

Theileriosis is spread by the brown tick (Rhipicephalus appendiculatus) and results in a swelling of the lymph nodes, running eyes, rough skin and loss of appetite and later almost certain death, especially with older, weaker animals. In periods of relatively good rainfall, tick populations explode and if they are not controlled through dipping, the disease often spreads to epidemic levels.

Other significant tick-borne diseases include Babesiosis, Anaplasmosis, and Heartwater. Additionally, viral diseases like Bovine Viral Diarrhoea (BVD) and Foot and Mouth Disease (FMD) also impact cattle health.

Nearly all parts of the country have been affected including in areas in the notionally drier areas where usually ticks do not survive. Small-scale farmers, in particular, are reeling. Some have lost their whole herd; while others were hoping for divine intervention.

Those who were forced to selling were getting pathetic prices, with buyers coming to collect sick animals for a song. Cattle are vital assets — for ploughing, transport, manure, milk, meat and so on — and have great cultural and social value — as savings, foci for sharing, exchanges for bridewealth, etc, so this sort of loss is devastating.

The overall statistics that Zimbabwe has lost half a million animals worth US$150 million over the last four years are shocking. But this still does not reflect the actual consequences of loss of animals by individual households. In the absence of draught power many small farmers resort to zero village. But a common challenge is that this was insufficient to meet their basic food needs. Worse still in the resettlement areas with around five hectares of arable land it means that most of it is left as fallow if tractors could not be hired. Regrettably, the result is likely to be more ticks in fallow fields with the cycle repeating itself.

Why is January disease so prevalent these days?

According to the Department of Veterinary Services, the following are some opf the major causes:

• The tick vectors are much more widespread and prevalent, with tick challenge high in nearly all areas. This is the result of periods of high rainfall in recent seasons with lots of grass growing. Following land reform, there is more grass, so more ticks in more places where people’s animals graze, resulting in a new distribution of ticks and disease.
• With the new configuration of land use following land reform, there are more animals spread across the country, but few dips especially in the resettlement areas. Along with the relaxation (or actually lack of implementation) of dipping regulations, animals are dipped infrequently and often not thoroughly.
• Some argue that the dip chemicals are not as good as they were with some being ‘fake’ and many being adulterated, although importers and manufacturers and Vet officials deny this. Not surprisingly, the low efficacy alternatives are more affordable cheaper and, therefore, sell fast..

• Senior officials in the Vet department have in the past bemoaned the lack of quality control. Whether it is the chemical or its mixing or application remains unknown, but this remains a possibility as fake drugs and chemicals are widely available in agro-supply stores (we visited one in Chiredzi and the very informed shop assistant pointed to which was which as we enquired about dipping chemicals.
• Infrequent dipping and misapplication of dips may have resulted in resistance to dip chemicals (acaracides) by the ticks. Compared to the heavily grazed communal areas, ticks survive better in the new resettlements. In the past it was the commercial farms that suffered the disease most, but now it’s widespread. Grazing animals are exposed to ticks that survive in refuges and spread fast when sudden rainfall occurs. Others argue that there are new vectors among the wider array of ticks found in these grazing environments, extending the range of tick vectors.
• The mixing of breeds in both the communal and resettlement areas that resulted from the dispersal of commercial breeds across the country in the wake of the Land Reform Programme has probably meant less overall resistance to ticks and tick-borne disease. Hardy, small Mashona cattle could survive nearly anything, but this is less the case with exotic crosses, resulting in declining resistancein the population. With some investing in pure breeds as they stock their A2 farms, many succumb very quickly, one farmer pointed out.

Local response and innovation 

There has been much research on theileriosis and the brown tick in Zimbabweand Southern Africa more broadly. It should be an easy disease to control and indeed in the past it was so. The regular dipping programmes that were instituted across the country since colonial days kept the tick and so the disease at bay. Occasionally there were new outbreaks, but they were soon under control. The recent devastation of cattle populations is very different, and the Veterinary Department and ministers of agriculture are constantly urging cattle owners to dip, whether through the conventional immersion dip or through spray dipping.

As the officials point out it’s important to have the right chemicals, to ensure that animals are properly soaked, to add tick grease to parts of the body where ticks attack that are not usually dipped (such as ears) and to increase dipping frequency if the disease emerges.

The 5-5-4 dipping regime is usually recommended, with dips spaced five, then four days apart. But it isn’t working and although the Government is investing in vaccine development, with 20,000 already being tested, this is a costly alternative to vector control.

January disease’ may be causing havoc but Zimbabwean farmers do not give up, thanks to the availability of extensive epidemiological knowledge and an array of innovative practices. These include feeding sick animals Chibuku beer, giving them cooking oil (or combinations of beer and oil, soaking medicinal plants for infusions and administering smoke from certain plants.

Apart from January disease, cattle are also susceptible to:

• Babesiosis (Redwater):

Another tick-borne disease caused by a parasite that affects red blood cells, leading to anaemia and other symptoms.

• Anaplasmosis (Gallsickness):

Similar to Babesiosis, this disease is also transmitted by ticks and causes anaemia, fever, and other symptoms.

• Heartwater:

A tick-borne disease caused by a parasite that affects the heart and blood vessels, leading to various symptoms like fever, dyspnea, and lethargy.

In the next instalment, this column will look at viral diseases, notably

Bovine Viral Diarrhoea (BVD) and Foot and Mouth Disease (FMD).

Briefly, BVD can cause respiratory and reproductive problems in cattle, leading to decreased productivity and increased mortality. On the other hand, FMD is a highly contagious viral disease affects various species, including wildlife, and can cause lesions in the mouth, feet, and other areas, leading to significant economic losses.