Drought Feeding
By Dr Mackie Hobson BSc(Agric),BVSc

Times of drought keeping the goats alive.

Drought is possibly the greatest factor that influences the economics of livestock production enterprises in South Africa.

Types of drought:

1. Protein drought – It is the same as a normal winter with sufficient dry veld Protein is the only nutrient that is deficient.
2. Protein and energy drought – It is the same as a normal late winter when the quality as well as the quantity of veld are a problem. Under these circumstances it is important that protein and energy are supplemented to prevent large mass and reproduction losses.
3. Total drought – Total drought situations will vary between the normal late winter and a disaster drought where no roughage from the veld is available.

The most important nutritional consideration is to recognise that two systems must be fed at once:

1. The microbes that reside in the rumen and which digest plant material, which is termed fermentative digestion.
2. The goat itself which largely depends on the products of fermentative digestion and dietary nutrients that bypass fermentation for its requirements.

The important point is that when ruminants are fed drought-based diets, the products of fermentative digestion are seldom balanced (in the quantities of individual and essential nutrients) to meet productive functions or even maintain body weight.

With pregnant and lactating animals it is always necessary to feed for the maintenance of the foetus and for maintenance of a minimal milk production. Research projects in which animals are fed for maintenance, it has been illustrated that these animals are highly inefficient in utilising feeds if the nutrients available are not in balanced quantities. More importantly, however, is that there is a large potential reduction in total feed requirements for maintenance of animals when nutrients are balanced. Balancing diets for ruminants in supplementary feeding situations will result in animals in much better condition at the end of the drought, because they use the available feed more efficiently.

• In times of drought, roughage is scarce and often very expensive. Research has indicated that animals can survive more successful and more economical on concentrate-rich ingredients.

Research has indicated that animals receiving daily survival diets performed poorer and had a higher mortality rate than animals that had been fed twice or just once a week.

What are the minimum requirements of the Angora goat?

1. Energy

Goats eat primarily to satisfy a need for energy. Experiments have determined the energy requirements Angora goats require for maintenance. The practical importance of energy requirements applies mostly to non-grazing systems such as feeding schemes in kraals to overcome serious droughts. Under such conditions a maintenance ration is usually fed just to keep animals alive. Supplementary feeding on Karoo veld during times  of drought when the veld is unable to sustain production should  emphasize energy-rich supplements followed by protein and minerals as the second and third limiting nutrients, under these circumstances.

 Energy value in a feed: Metabolizable Energy (ME)

TABLE 1 Maintenance energy requirements of Angora goats (keep alive) MJ/day

(M.J. HERSELMAN and W.A. SMITH)

1. Protein

Protein requirement for maintenance and pregnancy

• Minerals and Vitamins

See https://www.angoras.co.za/page/vitamin-and-mineral-supplements-requirements-for-angora-goats#122

Licks and Feed Recipes (Dr J van Rooyen)

1. Energy lick

• Intake should be less than 270g per 50kg body mass to limit salt intake
• Rock salt should be given to goats not previously exposed to salt for 7 days before giving lick.

1. 2: Protein lick

• Rock salt should be given to goats not previously exposed to salt for 7 days before giving lick.
• Intake should be less than 200g per 50kg body mass to limit salt intake

1. Kreep feed

• Feed ad lib

1. Full feed for ‘lamhokke’

• Start ewes 4 weeks before kidding starting with 200g/day and double every 3^rd day
• Single ewes need 1.0-1.5 kg and twins 1.5-2.0 kg/day
• Ewes can eat 2.5-3.0% of body mass in late pregnancy and 3-4% in early lactation.
• If ewes fed in groups then lucern hay needs to be offered as some ewes will not eat the ration.

1. Chocolate mielies

• First mix smallest ingredients in water then molasses powder then mielies.
• First feed 50g per day for 3 days then 100g for 3 days then 200g for 3 days.
• Normally feed no more than 350-500g/day
• Flush feeding 100g/day
• Winter feeding 200g alternate days
• Urea can cause problems in pregnant and lactating ewes

1. Bloat lick

• Follow normal bloat precautions: make roughage available before feeding pasture.Not all goats will take the lick.

SEE licks: https://www.angoras.co.za/page/licks_lekke#106

Other Drought Feeds

1. Lucerne

See Articles:

Angora goats on Lucern)

https://www.angoras.co.za/page/angora_goats_on_lucerne#108

Lucern Hay

https://www.angoras.co.za/page/lucerne_hay#100

2. Oldman saltbush (Atriplex nummularia)

If the drinking water is brackish (high total salts content), an adaptation period of two to three weeks should be allowed for animals to adapt to the very high total salt intake. After this adaptation period, feed intake and animal performance are the same as animals receiving fresh water (studies by King 1991). Apart from the drought resistance, a noteworthy characteristic of these plants is their high production of green succulent feed under relatively poor moisture conditions.  Oldman saltbush has the ability to recover after defoliation each year. Oldman saltbush is high in protein (16-22%) and can supply the maintenance requirements. It can also maintain ewes during late pregnancy and lactation, but for optimum production and reproduction, additional energy should be supplemented.

3. American aloe (Agave americana)

American aloe is one of the hardiest plants which can be established for the production of fodder in the arid and semi-arid regions. American aloe has low protein (3-4%) content. An extensive study on the utilisation of American aloe as a feed source for sheep at Grootfontein has indicated that American aloe leaves were able to satisfy 64% of the maintenance requirements of mature sheep, but that the best results were obtained at an inclusion level of 45% in maintenance diets. It was concluded that the most important applications of American aloe would be as a survival diet (e.g. during serious drought conditions) or as a major component of a maintenance diet. (Hoon, 1994).

The frequent incidence of lameness in some animals receiving a diet containing American aloe - presumably those ingesting too much of it - presents a serious problem to farmers in the semi-arid areas where American aloe is commonly used for drought feeding. Investigation of this lameness problem revealed that the primary cause of the condition is an acid-overload resulting from large intakes of American aloe, which has a relatively low pH (approximately 4,3). Observations of these affected animals suggested some resemblance to the "stiffness" syndrome seen in ruminants suffering from a grain-overload. Therefore a similar approach to that used to overcome the problem of grain-overload and subsequent acidosis, and which led to the "alkali-ionophore" treatment of grain (chocolate grain), was basically followed in this case. -a neutral pH of 7. Thereafter chopped American aloe was treated similarly by adding half a percent of slaked lime to it, while mixing it in a concrete mixer. Secondly, these results indicate that this condition can be prevented by alkalinization of the fodder with slaked lime to increase the pH to an acceptable level for the ruminant. (D Wentzel).

The higher effective degradabilities obtained for the various components of American aloe on the 45% American aloe: 55% Lucerne diet, indicate that the inclusion of this proportion of American aloe in the diet, established the optimum rumen condition for the functioning of cellulolitic bacteria which is mainly responsible for the digestion and degradation of the cell wall contents.(Hoon, King).

Animal performance was not significantly (P

4. Noors

In times of drough noors can be an excellent provider of roughage which can be supplemented with a concentrate source. The noors can be chopped into 10-15cm lengths but results in wastage and labour costs. Milling machines will reduce the labour costs and wastage. The alternative is leave the noors in place in the veld. Goats can maintain their body weight on ‘gekerfde’ form but it is advised to provide a protein supplement.