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1.
The objective of the study was to determine monthly changes in body condition scores, body weights and on the prevalence of
internal parasites in Nguni, Bonsmara and Angus steers raised on sweetveld. Body condition scores (BCS), body weights (BW),
packed cell volume (PCV) and monthly faecal egg counts (FEC) were determined in 25 Nguni, 15 Bonsmara and 15 Angus steers.
Nguni and Bonsmara steers maintained their body condition throughout the study, while the Angus lost condition. The Nguni
had the highest PCV levels. The PCV levels tended to decline during the rainy season for all the breeds. The FEC were generally
low. Fasciola spp. and strongyle eggs were found in 16.3 and 54.6% of the collected faecal samples, respectively. Of the three breeds,
Nguni steers had the lowest parasite infestation levels, with the Bonsmara being more susceptible than the other two breeds.
Generally, the egg counts observed throughout the study were low. 相似文献
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This study was conducted to determine the economic weights of most preferred traits in young breeding Nguni bulls and first parity cows. Fifty-four farmers from low-input cattle production enterprises participated in the choice experiment. Sixteen individual animal profiles were formulated from four traits of three levels each using a fractional orthogonal design of SPSS 14.0 (2005). 120 pair-wise choices were deduced for each breeding animal class. A total of 6480 (54×120) observations were obtained for each class of the animals. Data was subjected to multinomial logit (MNL) models using econometric software NLOGIT 4.0.1 Version (2007). All computed economic values for bull traits were significant (p<0.05). The economic weights of bull traits were poor body condition score (−0.99±0.095), good body condition score (0.45±0.073), over-conditioned (base level), low tick infestation (0.57±0.103), medium tick infestation (0.58±0.084), high tick infestation (base level), high aggression and mating behavior (4.41±0.095), average aggression and mating behavior (2.53±0.094), and low aggression and mating behavior (base level). The economic weights of first parity cow traits were poor body condition score (−0.06±0.055), good body condition score (1.08±0.061), over-conditioned (base level), low tick infestation (1.50±0.059), medium tick infestation (0.83±0.067), high tick infestation (base level), age at first calving of ≤27 months (2.37±0.068), age at first calving of 27–36 months (1.30±0.076), and age at first calving of >36 months (base level). Farmers were willing to pay R37,939 (US$4864) for a bull with high aggression and mating behavior score and R17,185 (US$2203) for a first parity cow of less than 27 months old. Enterprise ownership and demographics factors of the farmers were significant in determining economic weights within trait levels. Economic weights were high for reproductive efficiency of the breeding animals followed by the high adaptive characteristics. The choice experiment procedure can be the tool for determining importance of animal characteristics under low-input production systems. It is recommended to make use of the economic weights of preferential traits in designing selection models. 相似文献
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N.O Mapholi A. Maiwashe O. Matika V. Riggio C. Banga M.D. MacNeil V. Muchenje K. Nephawe K. Dzama 《Tropical animal health and production》2017,49(6):1201-1210
The objective of the study was to characterise genetic parameters across months for different tick species and anatomical locations in South African Nguni cattle. Tick counts were conducted monthly, over a 2-year period, on 586 Nguni cattle under natural infestation, from four herds located in different provinces of South Africa. The counts were recorded for six species of ticks (Amblyomma hebraeum, Rhipicephalus evertsi evertsi, Rhipicephalus decoleratus and microplus (Boofilids), Rhipicephalus appendiculatus, Rhipicephalus simus and Hyalomma marginatum) attached on eight anatomical locations on the animals and were summed by species and anatomical location. Heritability estimates, phenotypic and genetic correlations were estimated on a monthly basis using mixed linear models, fitting univariate and bivariate sire models. Fixed effects considered were location, sex, year and age as a covariate. Tick counts were higher in the hot months, and A. hebraeum was the most dominant tick species. Heritability estimates for tick count varied by month and trait and ranged from 0 to 0.89. Genetic correlations were mostly positive, and low to high, with some negative correlations with high standard error. Phenotypic correlations were low to moderate. In general, high genetic correlations were observed between whole body count and the anatomical location counts, suggesting that it may not be necessary to conduct whole body counts. Counts from the belly and perineum appeared to be the most suitable surrogate traits for whole body count. These findings provide useful information for developing strategies for the practical implementation of genetic selection, as a supplement to the traditional tick control measures. 相似文献
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The time budgets and daily milk yield of Jersey and Friesland cows and their crosses were compared in a pasture-based system by recording the time spent grazing, drinking, lying, standing and walking in four seasons of the year (cool-dry, hot-dry, hot-wet and post-rainy). Observations were made from 0800 to 1400 hours on seven cows per breed. Seven observers monitored the cows at 10-min intervals for 6?h using stop watches. Time spent standing was higher (P??0.05) across the genotypes in the hot-wet season. In the cool-dry season, differences in time spent grazing (P??0.05) in the same season. The Jersey cows spent the longest time walking (P?相似文献
6.
Lizwell Mapfumo Voster Muchenje John F. Mupangwa Michiel M. Scholtz 《Tropical animal health and production》2017,49(7):1383-1392
The objective of this study was to determine the changes in biochemical indicators for nutritional stress from a herd of Boran and Nguni cows. A total of 40 cows (20 from each herd) were randomly selected for the study. The animals were identified according to their parities as follows: parity 1 (n = 8), parity 2 (n = 16), parity 3 (n = 8) and parity 4 (n = 8). Serum chemistry levels of glucose, total cholesterol, urea, creatinine, albumin, globulin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutylaminotransferase (GGT), leukocytes, erythrocytes, haemoglobin, packed cell volume (PCV) and platelet counts were determined for 12 consecutive months spanning across the wet and dry seasons. The Boran cows had different creatinine concentration levels at different parities. The Boran cows in parity 1 had the highest (P < 0.05) concentration of creatinine 87.2 ± 5.17 μmol/L than other cows in different parities within the herd. There were significant differences in enzymes such as AST, ALP and ALT among the herd and parities. Boran cows in parity 3 had the lowest (P < 0.05) AST concentration levels of 52.6 ± 3.48 U/L, Nguni cows in parity 4 had the highest concentration of ALP of 161.3 ± 8.10 U/L while Nguni cows in parity 1 had the highest concentration level of ALT 55.1 ± 1.56 U/L than all the cows within the same herd. The Nguni herd had significantly higher (P < 0.05) levels of creatinine in both the wet (97.8 ± 3.27 μmol/L) and dry seasons (108.7 ± 3.29 μmol/L) compared with the Boran herd. Cows from the Nguni herd maintained significantly higher amount of urea, creatinine, albumin and total protein in both the wet and dry seasons as compared with cows from the Boran herd. Cows from the Nguni herd maintained significantly higher amount of urea, creatinine, albumin and total protein in both the wet and dry seasons as compared with those from the Boran herd. 相似文献
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Tawanda Marandure Godswill Makombe Baldwin Nengovhela Phillip Strydom Voster Muchenje 《African Journal of Range and Forage Science》2016,33(3):199-206
The objective of this study was to examine the factors influencing smallholder producers’ potential to sell cattle and identify marketing opportunities for sustainable beef production in South Africa. A total of 95 structured questionnaires was administered to the Ncorha and Gxwalibomvu communities in the Eastern Cape province of South Africa. Average cattle herd size per household was higher (P < 0.05) in Ncorha (13.7 ± 1.9) than in Gxwalibomvu (11.3 ± 1.9). The logit model showed that households with few members, young farmers, Christians, large cattle herds, low income levels and access to extension services had high potential to sell cattle compared with other households (P < 0.05). Beef branding (～40% of respondents from each community), feedlotting (～30%), group marketing (～25%) and forward contracting (>5%) were mentioned as potential strategies for improving commercial marketing of cattle in the studied areas. Most producers (70%) indicated their potential and willingness to participate in developing a natural pasture-fed beef brand. Overall, commercial marketing of beef cattle raised on communally owned natural pastures in the surveyed areas in South Africa was largely determined by farmer’s demographic characteristics, cattle herd size and access to extension services with branding and feedlotting as the major opportunities for improving sales. 相似文献
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Khetani TL Nkukwana TT Chimonyo M Muchenje V 《Tropical animal health and production》2009,41(3):379-384
The objective of the current study was to determine the effect of quantitative feed restriction on the performance of broilers.
A total of 270 unsexed broilers were randomly allocated to three treatments: with no feed restriction (T1), one week (T2)
and two (T3) weeks of feed restriction from 22 days of age and then fed ad libitum until the age of 42 days. Treatments were replicated three times with 30 birds per replicate. Birds were fed with starter,
grower and finisher diets. The feed consumed and body weights were recorded every week from the third to the sixth week. The
average daily gain (ADG), average daily feed intake (ADFI) and the feed conversion ratio (FCR) were computed for each week.
At Week 6, body weights of T3 birds were similar (P > 0.05) to those of T1 and T2 birds. There were also no treatment effects on the ADG at Week 6. In addition, no treatment effects
(P > 0.05) were observed on ADFI at each stage of growth. Since ADFI and FCR were similar among the three groups, it was concluded
that feed restriction by limiting the time to eat was not successful. There was also no evidence of compensatory growth in
the restricted groups. 相似文献
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The objective of the study was to determine the effect of supplementing Moringa oleifera leaves (MOL) on growth performance, carcass and non-carcass characteristics of crossbred Xhosa lop-eared goats. A total of
24 castrated goats aged 8 months, with a mean initial weight of 15.1 ± 2.3 kg, were randomly divided into three diet groups
with eight goats in each. The duration of the trial was 60 days. All goats received a basal diet of grass hay (GH) ad libitum
and wheat bran (200 g/day each). The MOL and sunflower cake (SC) groups were fed additional 200 g of dried M. oleifera leaves and 170 g of SC, respectively. The third group (GH) did not receive any additional ration. The crude protein of MOL
(23.75%) and SC (23.27%) were higher (P < 0.05) than that of the GH diet (14.08%). The attained average daily weight gain for goats fed MOL, SC and GH were 103.3,
101.3 and 43.3 g, respectively (P < 0.05). Higher (P < 0.05) feed intakes observed were in SC (491.5 g) and MOL (490.75 g) compared with GH (404.5 g). The hot carcass weight
was higher (P < 0.05) for SC (10.48 kg) and MOL (10.34 kg) than for the GH group (8.59 kg). The dressing percentage in SC (55.8%) and MOL
(55.1%) were higher (P < 0.05) than that of the GH (52.9%). The growth performance and carcass characteristics of SC and MOL goats were not different.
Feeding MOL or SC improved the growth performance and carcass characteristics of goats in an almost similar way, which indicates
that M. oleifera could be used as an alternative protein supplement in goats. 相似文献
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