DAIRY PRODUCTION SYSTEMS CHARACTERIZATION IN URBAN AND PERIURBAN AREAS OF CENTRAL OROMIA, ETHIOPIA, AND EFFECTS OF CONCENTRATE SUPPLEMENTATION ON PRODUCTIVE AND REPRODUCTIVE PERFORMANCES OF CROSSBRED DAIRY COWS
No Thumbnail Available
Date
2019-08
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The survey part of this study was conducted to assess urban and peri-urban dairy
production systems, major constraints and opportunities, available feed resources and
feeding systems in and around Assela, Bishoftu, Holetta and Sululta towns, Oromia
regional state, central highlands of Ethiopia. Overall, 160 dairy farmers (40 from each
site) were randomly selected for individual interviews using a pre-tested semi-structured
questionnaire. The feeding trial part was carried out in Bishoftu using twelve late
pregnant crossbred dairy cattle, grouped into three dietary treatments in randomized
complete block design (RCBD) to evaluate the effect of different concentrate rations
supplementation from late gestation to early post-partum on milk yield, milk composition,
early post-partum blood plasma metabolites, reproductive performances and fertility.
The treatments were T1 (hay with noug seed cake, wheat middling, and wheat bran), T2
(hay with noug seed cake, wheat middling plus ruminant premix) and T3 (hay with noug
seed cake, wheat middling, and ruminant premix plus commercial dairy concentrate). In
all groups, feeding was started 21 days before calving and continued up to 90 days in
milk and rations formulation was according to cow’s requirements and stage of
production. The data were analyzed using Statistical Packages for the Social Sciences
software version 20. The survey results showed that, the highest educational level
(diploma and above) was from Bishoftu town and the age group of most of the
respondents was 40-59 years. Ninety five percent of respondents from urban Bishoftu,
90% from urban Assela, 65% from urban Sululta, 55% from peri-urban Holetta areas
reported stall feeding as the primary feeding method. Artificial insemination was the
main breeding system in all (100%) of peri-urban Bishoftu, 90% of urban Bishoftu, 80%
of urban Assela, 65% of urban Holetta, 60% of peri-urban Holetta and 50% of urban
Assela. The higher average daily milk yields were 11.7, 11.2 and 10.8 liters in urban and
peri-urban Bishoftu and urban Sululta, respectively. The longest average age at first
service (29.3 months) and age at first calving (38.3 months) intervals were in peri-urban
Assela. The number of services per conception was 1.4 and 1.3 in urban and peri-urban
Assela and these were lower than 1.65 and 1.85 in urban and peri-urban Bishoftu. The
longest average calving to conception interval (168.0 days) was in peri-urban Assela.
The average calving intervals 14.9 and 13.9 months from peri-urban Assela and Sululta
were relatively longer than the respective urban areas.In peri-urban Bishoftu (85%),
Holetta (80%) and urban Bishoftu (70%) and peri-urban Sululta (70%) less milk price
relative to feed cost was the main marketing problem. High feed cost was the major
constraint of peri-urban Bishoftu (55%), Sululta (55%) and urban Bishoftu (50%). In
peri-urban Assela water scarcity was the main constraint following high feed cost.
randomly selected household respondents were involved in the study. Key informants
working in each beer factory and survey locations in the country were also
considered for the study. Household respondent and key informant interview were the
kind of survey methodologies employed to conduct the field study. Data from the
household based survey was collected using a pre-tested fully structured checklist.
The result showed that brewery spent grain also called brewer’s grain (BSG) and
brewer’s spent yeast (BSY) were the major byproduct feeds produced by all beer
factories in Ethiopia. There were in total 12 factories producing an estimated
26722.8 tons BSG (DM basis) and 360,758.1 hectoliters (hl) of BSY in 2016 G.C.
Roughage feeds consumed by a lactating crossbred cow was estimated at 3.5 kg, d-1,
with higher intake (P<0.05) recorded for cows in Sebeta district. Similarly, daily
concentrate, BSG, mineral salt, and total DM intakes were also found to be higher
(p<0.05) for lactating cows in the Sebeta district. According to the view of the
respondents, heavy reliance and long term feeding of BSG could bring about feedrelated
metabolic, productive and reproductive problems in dairy cattle. These were:
reproductive and metabolic disorders, and blindness in newly born calves. Moreover,
a third of all household respondents across the studied districts claimed to have
observed milk with less fat yield (P<0.05). Soaking of salt treated fresh BSG in cold
water, sun drying and ensiling in that order of importance were the most commonly
used local BSG conservational practices and showed great variation (P<0.05) across
the surveyed districts. Some 77.3% and 61.4% of smallholder dairy farms in the
Sebeta and Debre Birhan districts had better access to BSG supply compared to
farms in the Bedele district (P<0.05). Contrary to this, the factory gate price per quintal of dried BSG was much cheaper for farmers in Bedele, medium and costly for
farmers in Debre Birhan and Sebeta districts, respectively (P<0.05). On the other
hand, the study also had two lab-based studies aimed at investigating the effects of
aerobic and anaerobic conservation practices on nutritional compositions and fungal
load dynamics of fresh and BSG samples conserved according to local storage
practices. Accordingly, in the first 3X3 factorial experiment, an attempt was made to
determine an optimum storage durations for fresh BSG samples conserved under
varying aerobic storage duration and temperature conditions. Thus, under local
conditions, it would be safe to store and feed fresh BSG provided that it is stored for
less than 6 and 2 days at 15°C and 20°C, respectively (P<0.05) without being
exposed to aerobic deteriorations. In a second lab-based trial where local
conservation practices identified from the survey study have been evaluated for their
major proximate compositions, digestible organic matter in the dry matter (DOMD),
in-situ crude protein (CP) and dry matter (DM) degradability characteristics, and
fungal load dynamics using the model for a completely randomized design. The
ensiling technique outperformed (P<0.05) the remaining local conservation practices
of soaking and sun drying techniques. Lastly, an in-vivo trial was conducted using
eight early lactating crossbred cows (50% BXF) with a major objective to identify
and recommend optimum level of ensiled BSG that iso-nitrogeneously replaced
increasing levels of cottonseed cake (0, 33, 66 & 100%) from on-station used dairy
formula feed. A 4X4 Double Latin Square design was used to analyze the data set
generated from the feeding and digestibility trials. It has been observed that ensiled
BSG has fully (100%) replaced cottonseed cake from the dairy formula feed
substantially improving (P<0.05) total ration’s apparent digestibility for DM, CP,
neutral detergent fiber (NDF) and acid detergent fiber (ADF), daily milk yield and
milk production efficiency. However, associated to lower estimated metabolizable
energy (EME) intakes, heavy reliance on BSG based diet should be balanced for
dietary energy rich feedstuffs and roughage sources rich in short and medium chain
fatty acids to avoid sustained body weight loss, lower milk fat, and total solids.
Description
PhD Thesis
Keywords
apparent digestibility, brewery spent grain, fungal, household