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A deterministic evaluation of alternative management options for the smallholder dairy cattle production system in South Africa

Thesis (PhD (Animal Science))--University of Pretoria, 2020.

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Other Authors: Visser, Carina
Format: Thesis
Language:English
Published: University of Pretoria 2020
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access_status_str Open Access
author2 Visser, Carina
author_browse Visser, Carina
author_facet Visser, Carina
collection Thesis
dc_rights_str_mv © 2019 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Thesis (PhD (Animal Science))--University of Pretoria, 2020.
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institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:37:15.598Z
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provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2020
publishDateRange 2020
publishDateSort 2020
publisher University of Pretoria
publisherStr University of Pretoria
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source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/77152 A deterministic evaluation of alternative management options for the smallholder dairy cattle production system in South Africa Visser, Carina samuelabini@gmail.com Banga, Cuthbert Abin, Samuel Atanasio Mustafa UCTD Animal Breeding and genetics Benchmarking Bio-economic model somatic cell count Deterministic model Normative Partial budget Profitability Natural and agricultural sciences theses SDG-01 Natural and agricultural sciences theses SDG-02 Natural and agricultural sciences theses SDG-12 Thesis (PhD (Animal Science))--University of Pretoria, 2020. The aim of this thesis was to evaluate alternative management options for the smallholder dairy cattle production system in South Africa (SA). Specific objectives included, were to benchmark cow performance in the smallholder (SH) against their counterparts in a high-input system (H), to develop a SH herd model, and to evaluate alternative management options for the improvement of smallholder dairy herd profitability. Data on production (305-day yields of milk, fat and protein), lactation length, somatic cell count (SCC), and reproductive traits (age at first calving (AFC), and calving interval (CI) obtained from the South African National Dairy Animal Improvement scheme (NDAIS) were used in a benchmarking study. Least squares means per trait were compared between the two systems, and lactation curves for roduction traits and SCC were plotted. Results revealed that mean yields of milk, fat and protein were significantly (P<0.05) lower in the SH (4 097±165, 174±5.1 and 141±4.5 respectively) compared to the H system (6 921±141, 298±4.7, and 245±4.1, espectively). Mean lactation length was significantly (P<0.05) shorter for the SH (308±15.1) compared to the H system (346±12.8). Log-transformed SCC was significantly (P<0.05) higher in the SH (2.41±0.01) relative to the H system (2.27±0.01). Cows in H herds exhibited typical lactation curves, in contrast to flat and low-peaking curves obtained for the SH system. SH cows had significantly (P<0.05) older AFC (30±0.5) than those in the H system (27±0.5). There was no significant difference (P<0.05) in CI between the two systems. A bio-economic SH herd model was developed by adapting a previously developed model for the H system in SA. Parameters used were obtained from NDAIS, survey data, personal communications, and literature. The model integrated herd dynamics, outputs, nutrient energy requirements, management, and their associated economics. Nutrient energy requirements were estimated for maintenance, growth, reproduction, and lactation. The developed SH herd model was used to evaluate alternative herd management options, using the partial budget approach. Milk yield (MY), live weight (LW), AFC, and CI were used as indicators of cow performance. Herd management practices studied were herd size (HS), replacement rate (RR), feeding system (FS), breeding methods (natural service vs artificial insemination), and source of replacement heifers (raising vs. buying in). Improvements in profitability were attained by increasing MY or increasing herd size, using small to medium sized cows, or reducing AFC, CI or RR. Break-even points were 3 687.4 l/year, 500 kg, 29 months, 420 days and 25% for MY, LW, AFC, CI, and RR, respectively. Profitability was mostly sensitive to the prices of milk and feed. A drop in the price of milk below R4.50/l or increase in the cost of feed above R5.60/kg DM generally resulted in non-profitability. Relying on pasture only for feed was non-viable, and supplementation of pasture with concentrate was the most profitable feeding system. Feeding systems based on supplementation of pasture with concentrate, and silage were resilient to fluctuations in the price of milk, remaining profitable even when the price dropped to R4.10/l. Using artificial insemination or buying-in replacement heifers are additional management strategies that increase SH dairy farming profitability. These recommended management options should be used in combination for achieving maximum herd profitability. UP Postgraduate/Doctoral Research Bursary bs2026 Animal and Wildlife Sciences PhD (Animal Science) Unrestricted SDG-01: No poverty SDG-02: Zero hunger SDG-12: Responsible consumption and production 2020-11-24T11:46:50Z 2020-11-24T11:46:50Z 2021-04 2020 Thesis * A2021 http://hdl.handle.net/2263/77152 en © 2019 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle UCTD
Animal Breeding and genetics
Benchmarking
Bio-economic model
somatic cell count
Deterministic model
Normative
Partial budget
Profitability
Natural and agricultural sciences theses SDG-01
Natural and agricultural sciences theses SDG-02
Natural and agricultural sciences theses SDG-12
A deterministic evaluation of alternative management options for the smallholder dairy cattle production system in South Africa
title A deterministic evaluation of alternative management options for the smallholder dairy cattle production system in South Africa
title_full A deterministic evaluation of alternative management options for the smallholder dairy cattle production system in South Africa
title_fullStr A deterministic evaluation of alternative management options for the smallholder dairy cattle production system in South Africa
title_full_unstemmed A deterministic evaluation of alternative management options for the smallholder dairy cattle production system in South Africa
title_short A deterministic evaluation of alternative management options for the smallholder dairy cattle production system in South Africa
title_sort deterministic evaluation of alternative management options for the smallholder dairy cattle production system in south africa
topic UCTD
Animal Breeding and genetics
Benchmarking
Bio-economic model
somatic cell count
Deterministic model
Normative
Partial budget
Profitability
Natural and agricultural sciences theses SDG-01
Natural and agricultural sciences theses SDG-02
Natural and agricultural sciences theses SDG-12
url http://hdl.handle.net/2263/77152