Large Stock Unit Research Articles

Quantifying the Impact of COVID-19 Relief Vouchers Schemes on Food Security: Empirical Evidence Insights from South Africa

Livestock production systems are essential for sustaining household food security, especially in the drylands of Africa. This study assesses the impact of South Africa’s targeted Large Stock Unit (LSU) social protection program on the acute food insecurity effects of the COVID-19 pandemic among selected smallholder livestock farmers. An embedded research approach was utilized in four local municipalities purposively selected in the Northern Cape Province, where 217 households were selected using a stratified proportionate random method. A structured questionnaire was employed, while secondary data on beneficiary farmers were collected from implementing agencies. A full information maximum likelihood (FIML) Endogenous Switching Regression (ESR) model was adopted to capture variations due to self-selection bias among respondents. ESR model results show that the decision maker’s age, the household head’s education level, the land holdings’ size, average relative livestock losses, the orientation of production, and the level of external support impact food security. The study concludes that based on average treatment effects analysis, beneficiaries of the LSU program are better off in the household food security relative to their non-beneficiary counterparts. These findings validate the need for enhancing support initiatives during COVID-19 shocks for households to attain food security using their main livelihood sources as the gateway. Increasing the diversity of livelihood strategies in these vulnerable communities needs to be scaled up to protect households from acute food insecurity. Targeted support programs, including direct financing and binding networks, may also be supported through youth-sensitive training programs to enhance mitigations and resilience against COVID-19 acute food insecurity. A policy can tap into existing local structures and province-wide institutional platforms for the long-term sustainability of the LSU support initiatives and mitigation of COVID-19 food security vulnerabilities.

Alternative measures of cow–calf efficiency for Afrikaner, Bonsmara, Nguni, Angus and Simmental sired calves

Context It is desirable to identify cows that produce higher weaning weights while consuming less feed in order to increase biological efficiency; however, there is no universally accepted metric for cow–calf efficiency. Aim Due to the common usage of ratios to express biological cow efficiency, despite their theoretical defects, these measures and alternatives to them were examined to understand better some of the complexities in improving cow efficiency. Methods The analyses were carried out using SAS. In model 1, 205-day calf weight/cow weight was used to define cow–calf efficiency and in model 3, 205-day calf weight per Large Stock Unit (LSU), which is a standard unit of energy consumed, was used to quantify efficiency. In models 2 and 4, 205-day calf weight was analysed using cow weight and Large Stock Unit, respectively, as covariates. Key results The use of ratios was biased in favour of the smaller Nguni cows. The Bonsmara and Angus sired calves attained 53% of the weight of their Nguni dams, and their weaning weight per Large Stock Unit was 169 ± 9 kg. However, Angus sired calves from Bonsmara dams were most efficient when efficiency was determined by analysis of covariance when cow weight and Large Stock Unit were used as covariates (162 ± 17 kg and 133 ± 22 kg), respectively. Conclusions The results indicate the difficulty in determining differences in cow–calf efficiency in the absence of a standard definition. The difference between output and input can be maximised, when traits are reported in consistent units like joules, financial currency, or carbon footprint. Implications This inconsistent definition of cow–calf efficiency makes its improvement challenging.

The Environmental Impact of Changes in Cow Productivity and Its Component Traits in South Africa's Landrace Beef Breeds

Any reduction in the carbon footprint of beef production will contribute to future sustainability. This study investigates the environmental impact (carbon footprint) of the changes that occurred in cow productivity in the cowherds of four South African landrace breeds over a period of 25–30 years. Cow productivity, defined as kilogram calf weaned per large stock unit mated, increased by 18.3, 10.0, 14.2, and 10.4% in the Afrikaner, Bonsmara, Drakensberger, and Nguni, respectively. This resulted in a decrease in the carbon footprint, as defined by the enteric methane emissions factor, of between 6.6 and 12.0%. Changes in the cow productivity component traits, viz. weaning weight, cow weight, and fertility (as measured by inter-calving period) was also investigated. In all breeds, except the Nguni, the change in the environmental trends were less than that of the direct genetic or phenotypic trends. The genetic trends for direct weaning weight in the Afrikaner, Bonsmara, and Drakensberger were +6.7, +11.7, and +6.2 kg, respectively. In the case of the Bonsmara and Drakensberger breeds, the genetic trends were larger than the phenotypic trends, which may indicate that the environment cannot support the higher “genetic” weaning weights. The genetic trends for mature cow weight in Bonsmara and Drakensberger were +15.9 and +15.1 kg, respectively, whereas in the Afrikaner and Nguni it was not significantly different from zero (R2 ≤ 0.24). The trends in the phenotypic mature cow weights were −8.3, +17.5, +8.5, and −17.2 kg for in the Afrikaner, Bonsmara, Drakensberger, and Nguni, respectively. Although the observed inter-calving period of all breeds declined, there was no genetic change in inter-calving period for any of the breeds. It is proposed that selection indices are developed for cow productivity, which can be extended to a carbon footprint selection index. It is recommended that similar studies be done on all the major beef breeds in South Africa, especially those that rely on regular importation of genetic material.

Investigating novelty traits to improve cow-calf efficiency in South African Afrikaner, Angus and Charolais for climate-smart production

The aim is of the study was to identify novelty traits that could be used as breeding objectives to improve cow-calf efficiency and describe cow efficiency in extensive systems in support of climate-smart production in beef cattle. The traits that were investigated were ‘weaning weight of the calf as a trait of the dam’ (K205) and ‘kilogram calf weaned per large stock unit’ (KgC/LSU. The latter trait is a value that expresses performance (calf weaning weight) per constant unit, namely per LSU. This may be a useful breeding objective or goal to increase production efficiency, which may reduce the carbon footprint of extensive beef cow-calf production systems. The investigation of the novel traits was conducted on three diverse breeds, namely Afrikaner, Angus and Charolais, with 6104, 7581 and 2291 complete cow-calf records, respectively. Only cows with all three first parities recorded were used to investigate KgC/LSU and K205, as breeding objectives to improve cow-calf efficiency. The heritabilities for KgC/LSU were 0.52, 0.24 and 0.21 for the Afrikaner, Angus and Charolais, respectively, and for K205 were 0.40, 0.17 and 0.13 respectively. The genetic relationship between KgC/LSU and K205 for Angus and Charolais varied substantially. In Charolais cows a strong negative correlation (-0.75) was found, while a strong positive correlation (+0.84) was estimated in Angus cows. These results indicate that a ‘cow efficiency index’ in which several traits (production, fertility and efficiency) are included may be a more effective alternative breeding strategy. Breeding strategies and production systems to improve the production efficiency of beef cattle could play a significant role in reducing the carbon footprint and would enhance climate-smart beef production. Keywords: breeding objective, calf weight, cow weight

Sustainable crossbreeding systems of beef cattle in the era of climate change

Beef cattle are unique, because they not only suffer from climate change, but they also contribute to climate change through the emission of greenhouse gases (GHG). Mitigation and adaptation strategies are therefore needed. An effective way to reduce the carbon footprint from beef cattle would be to reduce the numbers and increase the production per animal, thereby improving their productivity. Sustainable crossbreeding systems can be an effective way to reduce GHG, as it has been shown to increase production. There are a wide range of different cattle breeds in South Africa which can be optimally utilized for effective and sustainable crossbreeding. This paper reports on the effects of crossbreeding on the kilogram calf weaned per Large Stock Unit (kgC/LSU) for 29 genotypes. These genotypes were formed by crossing Afrikaner (A) cows with Brahman (B), Charolais (C), Hereford (H) and Simmentaler (S) bulls and by back-crossing the F1 cows to the sire lines. A LSU is the equivalent of an ox of 450 kg with a daily weight gain of 500 g on grass pastures with a mean digestible energy (DE) content of 55% and a requirement of 75 MJ metabolizable energy (ME). Crossbreeding with A as dam line increased the kgC/LSU on average by 8 kg (+6%) - with the CA cross producing the most kgC/LSU (+8%) above that of the AA. The BA dam in crosses with C, H and S, increased kgC/LSU on average by 26 kg (+18%) above that of the AA dam, with the H x BA cross, producing the most kgC/LSU (+21%). The BA, CA, HA and SA F1 dam lines, back-crossed to the sire line breeds, increased kgC/LSU on average by 30 kg (21%), 21 kg (15%), 19kg (13%) and 26 kg (18%) above the that of the AA, respectively. The big differences between breeds in kgC/LSU provide the opportunity to facilitate effective crossbreeding that can be useful in the era of climate change. From this study it is clear that cow productivity can be increased by up to 21% through properly designed, sustainable crossbreeding systems, thereby reducing the carbon footprint of beef production.Keywords: Carbon footprint, cow productivity, kilogram calf, production systems

Direct greenhouse gas emissions of the game industry in South Africa

Previous greenhouse gas (GHG) inventories did not include game as an emissions source. Recently game farming has become a recognized commercial enterprise in the agricultural sector in South Africa, contributing approximately R10 billion to the sectorial gross domestic product. The objective of this study was to estimate methane (CH4) and nitrous oxide (N2O) emissions from privately owned game animals based on international recognized methodologies. The emissions were calculated on the basis of a large stock unit (LSU) selecting different quality diets. Daily enteric methane emissions were estimated as 0.28, 0.22, and 0.18 kg CH4/LSU/day consuming diets of 55%, 65% and 75% digestibility, respectively. The game industry contributed an estimated 131.9 Giga grams (Gg) of methane annually to agricultural emissions with the provinces of Limpopo, Eastern Cape and Northern Cape being the three largest contributors with 43.4, 37.3 and 21 Gg methane, respectively. The total privately owned game population was estimated at 299 1370 animals, utilizing 20.5 million hectares.Keywords: Methane, nitrous oxide, wildlife, emission factors

Long-term stability of grazing lawns in a small protected area, the Mountain Zebra National Park

We examined a heavily grazed plant community dominated by creeping grass species with the aim of, (1) determining its response to the exclusion of grazing and (2) its long-term persistence. This plant community was particularly favoured by wild ungulate species that prefer short grasses – blesbok (Damaliscus dorcas phillipsi), springbok (Antidorcas marsupialis) and black wildebeest (Connochaetes gnou). Exclusion of grazing by large herbivores by means of fencing resulted in the virtual disappearance of the creeping grasses and their replacement by tall tufted species. On plots that remained unfenced, the plant species composition was found to be little changed after an interval of more than 20 years. The number large stock unit equivalents (LSU) per ha carried by the plant community was used as a proxy for grazing intensity. Monitored for approximately 2 years at the start of the study, LSU per ha was found to greatly exceed levels recommended for commercial livestock production. This plant community conforms to a recently published definition of a grazing lawn, in that intense grazing promotes palatable, grazing-tolerant grass species.Conservation implications: The positive association between grazers and grazing-tolerant grass species evidently persisted for more than 20 years and there was no evidence of an increase in abundance of unpalatable plant species. Despite the small size of the park, which limited the extent of large herbivore movements, localised heavy grazing did not lead to range degradation.

Report on a breeding objective that may reduce the carbon footprint of extensive cow-calf production systems

Most measurements for beef improvement in South Africa are per individual (weaning weight, calving interval, growth rate, etc.). A measurement that expresses performance per constant unit, e.g. kilogram calf weaned per Large Stock Unit (LSU) can eventually be translated to kilogram calf produced per kg CO2 equivalent. A LSU is defined as a bovine requiring 75 MJ Metabolisable Energy (ME) per day. If more kilogram weaner calf can be produced per LSU (KgC/LSU), the carbon footprint of beef can be reduced. This study used breed average values to investigate the KgC/LSU for the 30 beef and dual purpose breeds in South Africa. The breeds were categorized in the following breed types: Sanga (indigenous to South Africa) Sanga derived, Zebu, Zebu derived, British and European. No relationship was found between cow weights and KgC/LSU, indicating that it is independent of cow weight between breeds. However, when the data is summarized into breed types, the Sanga and European breed types produce the least KgC/ LSU and Sanga derived breed types the most. This high value of the Sanga derived breeds is probably due to retained heterosis. Composite breeds are mostly intermediate to parental breeds for individual traits but superior for composite traits and KgC/LSU is a composite trait. These calculations were only done on breed averages. A genetic analysis on a breed level to estimate genetic parameters for this trait, and its genetic correlations with other traits now needs to be done before a decision can be taken whether selection for KgC/LSU will be feasible. The ultimate aim with a trait like this is to reduce the carbon footprint of weaner calf production since more kilogram calf will be produced per LSU (constant feed unit).

Effect of Nonprescribed Fire on an Atriplex lampa Community, in the Guadal Plateau of Mendoza Province, Argentina

The purpose of the present study was to determine the effect of a single nonprescribed fire on species community composition, woody and herbaceous species diversity, carrying capacity, density of dominating shrubs, and their resprouting capacity after fire. For short and long-term evaluations, two sites were chosen in a private extensive cattle ranch: (1) unburned areas and (2) burned areas. The forage total cover before fire (initial stage) was 54%; this cover decreased in burned areas to 13% (1986) and to 25% (2000), mainly due to a reduction in forage shrub cover. The cover of Atriplex lampa (zampa), the dominant forage shrub, decreased from 17.0 to 0.20% in 1986 after fire, and 15 years later this value remains constant (0.33%). The same area showed a carrying capacity, expressed in hectares per large stock unit (LSU), of 10 ha LSU−1 by 1986 and 17 ha LSU−1 by 2000, whereas in unburned areas it was 7 ha LSU−1, similar to prewildfire. All selected species that had been cut, simulating the action of fire, resprouted 1 year later, except zampa. We determined that the re-establishment of zampa plants in burned areas is extremely slow. Conditions as absence of adventitious bud/root crown and drought in following post-fire years may have determined the poor recovery of A. lampa.

The potential distributions, and estimated spatial requirements and population sizes, of the medium to large-sized mammals in the planning domain of the Greater Addo Elephant National Park project

The Greater Addo Elephant National Park project (GAENP) involves the establishment of a mega biodiversity reserve in the Eastern Cape, South Africa. Conservation planning in the GAENP planning domain requires systematic information on the potential distributions and estimated spatial requirements, and population sizes of the medium to largesized mammals. The potential distribution of each species is based on a combination of literature survey, a review of their ecological requirements, and consultation with conservation scientists and managers. Spatial requirements were estimated within 21 Mammal Habitat Classes derived from 43 Land Classes delineated by expert-based vegetation and river mapping procedures. These estimates were derived from spreadsheet models based on forage availability estimates and the metabolic requirements of the respective mammal species, and that incorporate modifications of the agriculture-based Large Stock Unit approach. The potential population size of each species was calculated by multiplying its density estimate with the area of suitable habitat. Population sizes were calculated for pristine, or near pristine, habitats alone, and then for these habitats together with potentially restorable habitats for two park planning domain scenarios. These data will enable (a) the measurement of the effectiveness of the GAENP in achieving predetermined demographic, genetic and evolutionary targets for mammals that can potentially occur in selected park sizes and configurations, (b) decisions regarding acquisition of additional land to achieve these targets to be informed, (c) the identification of species for which targets can only be met through metapopulation management,(d) park managers to be guided regarding the re-introduction of appropriate species, and (e) the application of realistic stocking rates. Where possible, the model predictions were tested by comparison with empirical data, which in general corroborated the predictions. All estimates should be considered as testable hypotheses.

Estimated spatial requirements of the medium- to large-sized mammals, according to broad habitat units, in the Cape Floristic Region, South Africa

Conservation planning in the Cape Floristic Region (CFR) of South Africa, a recognised world plant diversity hotspot, required information on the estimated spatial requirements of selected medium- to large-sized mammals within each of 102 Broad Habitat Units (BHUs) delineated according to key biophysical parameters. Spatial requirement estimates were derived for 19 omnivore and carnivore species, following a review and extrapolation of extant information. The estimates for 23 herbivore species were derived from a simple spreadsheet model based on forage availability estimates and the metabolic requirements of the species in question; this analysis incorporated adaptations of the agriculture-based Large Stock Unit (LSU) or Animal Unit approach. The LSU approach has various shortcomings but given the virtual absence of information on forage availability (quantity, quality and seasonality) for indigenous herbivores in the CFR, it provides the only extant measure of the influence of key biophysical factors on this parameter, especially at a regional scale. The outcomes of the exercise, viz. densities (hectares/animal), are presented here; these should be considered as testable hypotheses and a cautious 'management by hypothesis' approach should be adopted in their use. This information can be used to guide both conservation planning activities and practical conservation management decisions.

A pragmatic approach to estimating the distributions and spatial requirements of the medium‐ to large‐sized mammals in the Cape Floristic Region, South Africa

Abstract.Conservation planning in the Cape Floristic Region, a recognized world plant diversity hotspot, required systematic information on the estimated distributions and spatial requirements of the medium‐ to large‐sized mammals within each of 102 Broad Habitat Units delineated according to key biophysical parameters. As a consequence of a general lack of data, we derived a pragmatic approach for obtaining estimates of these two parameters. Distribution estimates were based on a combination of a literature survey (with emphasis on early texts) and the ecological requirements of the species. Spatial requirement estimates were derived from a simple spreadsheet model that is based on forage availability estimates and the metabolic requirements of the mammals in question. Our analysis incorporated adaptations of the agriculture‐based Large Stock Unit or Animal Unit approach. The predictions of the model were tested by comparing them with actual density data. The outcomes provided realistic estimates of the two parameters. However, they should be considered as testable hypotheses and the concept of adaptive management — or management by hypothesis — must apply. Examples of the outcomes are provided in the form of maps and tables.

Impacts of non-selective grazing on cover, composition, and productivity of Nama-karoo grassy shrubland

The non-selective rotational grazing system has undergone a long and controversial development. The merits of this grazing system, where relatively large numbers of livestock are herded into numerous small paddocks for short timespans with long rests between grazings, have not been formally evaluated in a long-term monitoring experiment in the Karoo. In this study we used exclosures (controls) on a 7 000 ha farm in the Central Lower Karoo, camped into approximately 50-ha paddocks, to evaluate the impact of this grazing system on certain vegetation parameters. We report on the first four years of monitoring, after each of four replicate paddocks had received four treatments (one treatment = 40 - 60 Large Stock Unit grazing days per hectare over a period of 2 - 16 days). Concentrated defoliation with concomitant trampling, dunging, and urinating did not influence the perennial species composition, and cover of this grassy, semi-arid shrubland. Changes over time in plant composition, and cover are explained by annual, and short-term (e.g. quarterly) rainfall rather than by grazing impacts. Ephemerals were not favoured by this grazing system, but litter was more abundant in the treatment than the control areas. The dominant grass, Eragrostis lebmanniana, and shrub, Pentzia incana, are resilient to this defoliation regime, and show signs of compensatory growth. As yet there is no evidence that non-selective grazing increases diversity, but the severe defoliation and trampling may enhance the biomass turnover rate, resulting in more vigorous, and productive plants in the grazed areas. Diversity is unlkely to change rapidly in response to grazing, largely because of the persistence of grazing-tolerant perennials. Concentrating mixed herds of livestock onto small areas with lengthy rests can be a useful tool for 'kick-starting' moribund karoo veld into greater productivity. Several of the impacts hold potential for restoring the rangeland quality of degraded areas, but this needs to be tested.

Evaluation of large stock unit equivalents for sheep

Evaluation of large stock unit equivalents for sheep

Calculating stocking rates for game ranches: Substitution ratios for use in the Mopani Veld

Determination of carrying capacity for mixed‐ or multi‐species grazing systems is complex. Commonly, each species is compared to the standard large stock unit (LSU) used in conventional agriculture. However, this approach does not allow for ecological separation, and thus overlooks the potential for using the specialised and complementary resource‐use habits of wild ungulates to maximise veld utilisation. The aim of this study was to quantify the overlap in ungulate resource‐use on a game ranch, and to demonstrate how these indices of overlap can be incorporated into substitution ratios for calculating stocking rates. Habitat utilisation patterns of Burchell's zebra (Equus burchelli,), blue wildebeest (Connochaetes taurinus), eland (Taurotragus oryx), gemsbok (Oryx gazella), giraffe (Giraffa camelopardalis), impala (Aepyceros melampus), kudu (Tragelaphus strepsiceros), and warthog (Phacochoerus aethiopicus), were studied on the Messina Experimental Farm. Indices of overlap were determined for spatial distribution, habitat selection, diet composition, and browsing height, and were calculated as the sum of the percentage points from each resource dimension that was common to both species. Grazer and browser animal unit substitution ratios are presented for each of the ungulates using the index of combined overlap, metabolic mass and a reference norm of a blue wildebeest (grazer) and a kudu (browser) respectively. It is proposed that these substitution ratios can be used to calculate stocking rates for game ranches in the Mopani Veld.

Short- and long-term effects of shrub management on vegetation in the Monte, Argentina

A comparison was made of plant cover, carrying capacity and diversity in areas of Monte vegetation at the Biosphere Reserve of Ñacuñán, Mendoza, Argentina, in 1982, 1984 and 1995. Treatments applied in 1981 were: control (untreated plots), selective hand-cutting, roller-chopping, and root-plowing. By 1995, woody cover was lower in root-plowed plots (27%) than in the others treatments (41–51%), and herbaceous cover was similar in treated (28–39%) and untreated areas (26%). Carrying capacity of treated areas (6–8 ha per Large Stock Unit (LSU)) was higher than in the control areas (12 ha LSU−1). Woody species diversity, quantified by the Shannon index, for both areas was similar in the study period (0·62), except in root-plowed sites in 1982 (0·0) and 1995 (1·3). Herbaceous species diversity was similar on treated (0·81) and untreated sites (1·2) in 1995. We could recommend less drastic treatments to improve carrying capacity.

Economic analysis of community‐based wildlife utilisation initiatives in Botswana

Financial and economic cost‐benefit models were applied to determine the worth of several planned community‐based, wildlife utilisation initiatives in Botswana, and to identify policy guidelines. Projects planned to incorporate small‐scale wildlife cropping. Rentals from safari‐hunting or wildlife‐viewing activities were found to have inherent viability, both financially and economically, particularly in the north of the country, where tourism is greatest. However, success is dependent on both good management and high densities of wildlife. In the Kalahari, game at low densities (more than 100 hectares per large stock unit) cannot be cropped profitably by communities and investments in game protection will result in economic gain. At higher game densities (between 100 and about 25 hectares per large stock unit), positive financial returns are possible with community‐based cropping but two considerations are important. First, investment in protection continues to pay economically and, second, cropping at c...

A comparison of four different standards of reference for the animal unit for Determining stocking rate

No single standard of reference for the animal unit (AU) for determining stocking rates has materialized. Often, therefore, it is not clear which standard of reference for the AU or which method of determining stocking rate has been used in the presentation, of research results. A comparison is made of four different standards of reference for the AU, namely; 1. the individual animal, 2. animal faiornass, 3. metabolic mass, and 4. the Large Stock Unit (LSU). In comparing these methods, as the standard of reference is able to characterize animals more accurately, their simplicity decreases but generality of application increases. The generality of application should be the primary factor influencing the choice of a standard of reference for the AU. However, to avoid prescription on which standard of reference and method should be used for determining stocking rate, a simple descriptive notation is proposed.