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SHEEP FEEDLOTS | DR JARRED MORRIS BVSc MSc (Agric)

April 27, 2024

Introduction Sheep feedlots represent a specialized and efficient system of raising weaner lambs for meat production in an intensive environment. Lambs are placed into feedlot pens, where they are fed a carefully formulated ration to optimize feedlot performance. Average daily gain, average daily feed intake, feed conversion ratio and carcass parameters should be measured. Due […]

SAVE THE DATE | FEEDLOT INFORMATION DAY | 19 JULY 2024

April 22, 2024

Ringworm

September 4, 2023

Do your calves have these strange hairless circular spots? It is a ringworm.Are you saying you get worms found in the skin? No, not to worry because ringworm is a fungal infection of the hair and surface layers of the skin. So, is it of much importance? Ringworm causes economic losses by affecting growth rates, especially […]

Lumpy Jaw in Cattle

September 4, 2023

Lumpy jaw is a disease of the jawbone caused by a bacterial infection called Actinomyces bovis. These bacteria form part of the normal flora in the mouth of ruminants. So then how does it cause disease? The bacteria enter the soft tissue of the mouth through open wounds. These wounds can be caused by foreign […]

Snow Cow Nature Animals Cattle Field Fields

May 6, 2019

Mud and Lameness in Beef Cattle

Melting snow and spring rains produce conditions that can increase lameness in beef cattle. Mud is among the predisposing causes for cattle lameness. Wetness decreases hoof hardness and increases the incidence of claw lesions. Research has shown that nearly one-third of the total water absorbed by the hoof happens during the first hour of exposure to high moisture resulting in heavier and softer hooves. Although not as prevalent as observed in the dairy industry, when it happens it may lead to decreased feed intake, lower weight gains, reduced reproduction (both in cows and bulls), and greater culling rates. Beef producers address muddy conditions by creating mounds where cattle can lay down on higher, drier ground. There is a minimal cost to establish a mound particularly when the shaping takes place previous to installing fences, bunks, watering and aprons. With a slope of 3% – 5%, mounds work best when built parallel to the direction of the slope and are located in the center line of the pen. In older lots these mounds can be newly built or strengthened periodically by adding manure and dirt. Mounds however do not last forever and more than likely will need some reshaping with additional material yearly. The main concern is when either by accident small rocks or pebbles are present in the material used to build them. Standing cattle apply a significant amount of pressure to any surface. In a 2017 University of Kentucky article researchers compared this pressure with that of other livestock, […]

April 25, 2019

AIP in the Feedlot

AIP in the Feedlot AIP is the acronym for Acute (or Atypical) Interstitial Pneumonia. This disease is known by various different names over the years, such as Acute Bovine Pulmonary Emphysema and Edema, Bovine Asthma, Feedlot Dust Pneumonia, Fog Fever and the list goes on. It is a primary respiratory disease that leads to severe edema and emphysema of the lung tissue that leads to death in the majority of cases. This is documented to be the second most important respiratory disease affecting feedlot cattle. The financial impact of AIP can be significant, since it normally affects cattle in the finishing stage of their feeding period, animals which by that time increased in value to the producer due to increased weight – the result of various costly inputs. Outside the feedlot setting, AIP is reported (often as outbreaks) on lush green pastures and fermented crops. Especially when moving animals from low quality roughage, to high quality pasture that have high protein levels. With a sudden increase in protein levels, L-Tryptophan (a common amino acid/or protein building block) is converted to 3-Methylindole (3-MI) in the rumen by bacterial species such Lactobacillus. 3-MI is then readily absorbed through the rumen into the bloodstream, and when it reaches the lungs it gets converted to 3-Methyleneindolenine (3-ME) and this molecule is then responsible for causing the damage to the lungs seen in AIP. The above description is accepted as the etiology for Fog Fever. In the feedlot setting however, there are no […]

March 17, 2019

Foot & Mouth Disease – Vhembe Outbreak & Surveillance Update

Introduction & Summary On 7 January 2019, an outbreak of Foot and Mouth disease (FMD) was confirmed in cattle in the Vhembe district of Limpopo Province. The outbreak occurred in the high surveillance area of the FMD Free Zone, immediately adjacent to the protection zone. The outbreak was reported to the World Organisation for Animal Health (OIE) and as a result South Africa lost its FMD free zone without vaccination status. Map 1: Location of the FMD Outbreak in the FMD Free Zone of South Africa Outbreaks Reported Up to 15 February 2019, 5 positive locations have been confirmed by the Transboundary Animal Disease programme of Onderstepoort Veterinary Research. It is reported to the OIE . These locations are all in close proximity within the Disease Management Area that was declared in Limpopo Province. The affected animals are cattle kept in rural villages with communal dip tanks and grazing. Control Measures Implemented A Disease Management Area was declared and the details published in the Government Gazette. This area is enclosed by the R81 Road, the R36 Road, N1 and the R524 Road. Map 2: Area defined as the FMD Outbreak Management Area A Joints Operations Committee (JOC) was establish. And meets on a daily basis, consisting of Traffic, Departmental and District Disaster Management, Police, Industry (The National Animal Health Forum, Feedlot Association) and Provincial and DAFF veterinary officials. The JOC was facilitated the placement of 16 road blocks at strategic points. A Veterinary Operations Committee (VOC), which meets daily, was […]

March 17, 2019

Rift Valley Fever

Rift valley fever is viral disease of sheep, goats and cattle, transmitted by mosquitoes.The disease is characterized by causing abortions and deaths in young animals, and can have catastrophic consequences in naïve herds.Outbreaks seem to occur in cyclical patterns, once every 9-11 years (on average), during wet rainy periods. Late summer is usually the peak time when clinical disease is seen in an outbreak.The agricultural and veterinary community is of opinion that South Africa is the brink of another impending outbreak, very possibly this coming summer, and vaccination of all susceptible animals are advised. Remember to order vaccines before the summer (to ensure availability) and vaccinate at the start of spring. Since the disease is transmitted via mosquitoes, animals near large water bodies tend to be more exposed, since mosquitoes hatch in large numbers in water, especially in wet warm conditions. It is also important to remember that RVF is a Zoonoses, in other words, humans can also contract the disease. Although most people will recover after two weeks of flu-like symptoms, it can also cause severe illness, meningitis, blindness, liver failure and even death. Be sure to take protective measures (clothing, goggles, gloves, etc.) when working with animals and/or carcasses that possibly have RVF. Since the disease is transmitted via mosquitoes, animals near large water bodies tend to be more exposed, since mosquitoes hatch in large numbers in water, especially in wet warm conditions. It is also important to remember that RVF is a Zoonoses, in other words, humans […]

March 17, 2019

Redgut

Redgut (rooiderm) is a disease seen in feedlot cattle, characterized mostly, by sudden death and pronounced dark red small intestines seen at the necropsy (refer to figure1). The condition is referred to by many names, such as Jejunal Haemorrhage Syndrome, or Haemorrhagic Bowel Syndrome of Cattle, but most commonly referred to in South Africa as Redgut/Rooiderm. The scientific name however is Clostridium Enterotoxaemia, referring to the offending agent and its mechanism of action (destruction?) inside the animal. Redgut is a sequela of acidosis. Although it is important to note that not all animals that died from acidosis will have redgut, all animals that contract redgut will have a degree of acidosis. The exact mechanism of the disease is uncertain, but seems to be connected to an overgrowth of Clostridium perfringes Type A.Once an animal has acidosis, and the acidic content from the rumen reaches the abomasum and small intestines, it triggers an overgrowth of Clostridium perfringes Type A (a normal commensal bacterium in the bovine intestinal tract). These bacteria then release a toxin (enterotoxin), that severely damages the intestinal tract, causing excessive bleeding, cell death and sloughing of the tissue (see figure2). The damaged intestinal wall leads to the loss of electrolytes and the absorption of the offending toxin into the bloodstream. This induces toxic shock and severe metabolic disturbances that leads to death.There have been attempts to treat affected animals, with fluid-and electrolyte therapy, activated charcoal, and even surgery, all with very little success. In a feedlot […]