Digital Twins in Agriculture: Orchestration and Applications.

Digital Twins have emerged as an outstanding opportunity for precision farming, digitally replicating in real-time the functionalities of objects and plants. A virtual replica of the crop, including key agronomic development aspects such as irrigation, optimal fertilization strategies, and pest management, can support decision-making and a step change in farm management, increasing overall sustainability and direct water, fertilizer, and pesticide savings. In this review, Digital Twin technology is critically reviewed and framed in the context of recent advances in precision agriculture and Agriculture 4.

Dataset for the characterisation of thermal stratification in horizontally configured electric water heaters.

A test station was designed and built to measure the thermal stratification (vertical thermal gradients) in a horizontal 150 L electric water heater storage device for different external environmental and user-emulating inputs, ambient temperature, inlet water temperature, water draw flow rate, thermostat temperature and heating coil active time. Stratification measurement consists of 66 temperature sensors that coarsely map three-dimensional temperature gradients within the horizontally configured heating device, under different operational conditions. Other significant temperatures such as inlet, outlet, ambient, thermostat feedback, and wall temperatures were also recorded.

[The threat of wide dissemination of anthelmintic resistance by veld ram performance testing units].

A veld ram performance testing unit consists of an association of stud or commercial ram breeders, who compare the performance of selected rams under field conditions on common pastures. The best performers are subsequently auctioned at public sales. To date, at least 10 Merino veld ram clubs have been established in various centres in South Africa.

Parasites of domestic and wild animals in South Africa. XXV. Ixodid ticks on sheep in the north-eastern Orange Free State and in the eastern Cape Province.

The tick burdens of 115 Merino sheep, slaughtered over a period of 15 consecutive months on a farm in the north-eastern Orange Free State, were determined. A total of 7 ixodid and 1 argasid tick species were recovered and the seasonal abundances of Boophilus decoloratus, Hyalomma marginatum rufipes, Margaropus winthemi and Rhipicephalus evertsi evertsi were determined. One hundred and forty-nine Merino sheep were slaughtered over periods varying from 10 to 25 months on 3 farms in Eastern Province Thornveld in the eastern Cape Province and their tick burdens determined.

A novel approach to the control of anthelmintic-resistant Haemonchus contortus in sheep.

This paper reports attempts to control a resistant strain of Haemonchus contortus on pasture by replacing it with a susceptible strain. By making use of artificially infected donor sheep, six camps (paddocks) were seeded with a resistant field strain of H. contortus until it was confirmed by means of worm-free tracer lambs that the grazing had become infective.

South African field strains of Haemonchus contortus resistant to the levamisole/morantel group of anthelmintics.

A strain of Haemonchus contortus from the Pietermaritzburg district of Natal was found to be resistant to levamisole (geometric mean efficacy 76.5%), morantel (41.9%), the benzimidazoles (oxfendazole: 33.

[The efficacy of alphamethrin-impregnated ear tags against ticks].

The efficacy of 3 kinds of alphamethrin-impregnated ear tags was tested against natural Amblyomma hebraeum, Boophilus decoloratus, Rhipicephalus appendiculatus, and Rhipicephalus evertsi evertsi infestations of cattle. One type of ear tag was also tested in combination with a tail band of similar material. Ticks were counted macroscopically on their predilection sites.

[Benzimidazole resistant Ostertagia circumcincta in Angora goats].

Angora goat kids from the eastern Cape Province with natural infestations of Ostertagia circumcincta, Nematodirus spathiger, and Trichostrongylus rugatus were treated with albendazole, fenbendazole or morantel citrate, while a fourth group remained an untreated control group. The benzimidazoles were less than or equal to 50% effective against O. circumcincta, and approximately 50% effective against possibly resistant fourth larval stage N.

Bolus obstruction of the intestine. Case reports.

Two cases of intestinal obstruction caused by peaches are reported. In the first case steamed dried peaches were eaten by a 56-year-old woman who had undergone a Billroth I gastrectomy 18 years previously, while in the second case canned peach halves were swallowed whole by a 75-year-old edentulous man. The cases both typify the usual clinical setting of bolus obstruction, certain aspects of which are discussed.

Hepatic abscess in a patient with polycystic liver disease. A case report.

A patient with a liver abscess and underlying polycystic renal and liver disease is described. The liver abscess was diagnosed on the clinical findings and accurately localized by ultrasonography. Tube drainage and antibiotic administration resulted in a rapid recovery.

[Two cases of Ostertagia spp. in sheep showing resistance to benzimidazole anthelmintics].

Two field isolates of Ostertagia spp. of sheep from the Swellendam and Malmesbury districts in the south-western Cape were shown to be resistant to benzimidazole anthelmintics. At therapeutic dosage rates albendazole was 32,5%, thiabendazole 0%, oxfendazole 14,9% and morantel 91,4% effective against the adult stage of Ostertagia spp.

The efficacy of anthelmintics against Thysaniezia giardi in South Africa.

Two field cases of apparent inefficacy of albendazole against cestodes in lambs were investigated. In both farms Thysaniezia giardi was identified and 2 critical controlled trials were conducted to determine the efficacy of 5 anthelmintics against T. giardi.

The anthelmintic efficacy of albendazole against gastrointestinal roundworms, tapeworms, lungworms and liverflukes in sheep.

Anthelmintic trials were carried out to evaluate the efficacy of albendazole against helmi of 2,5 to 3,8 mg/kg administered orally, resulted in a 98,8 to 100% reduction of adult parasites of the genera Haemonchus, Ostertagia, Trichostrongylus, Nematodirus, Gaigeria, Oesophagostomum, Chabertia, Marshallagia and Cooperia. Against the immature stages of these genera, except for Marshallagia and Cooperia, which were not tested, a dose level of 2,5 to 3,8 mg/kg was 83,9-100% effective. Albendazole at 2,5 mg/kg was 99,0% effective against adult stages of Dictyocaulus; its activity at a dose of 3,8 mg/kg against the immature stages of D.