• Asian-Australasian Journal of Animal Sciences
• /
• 제13권7호
• /
• pp.883-887
• /
• 2000

One way of evaluating the effectiveness of a dairy breeding program is to measure response to selection. This may be direct or indirect. The objectives of this study were to estimate expected progress for direct selection on milk, fat and protein yields; to estimate the expected correlated responses on indirect selection for milk, fat and protein yields in Zimbabwean Holstein cattle and to establish the effect of selection intensity on responses. The Animal Model contained fixed effects of herd, year of calving, calving month, dry period, milking frequency and additive effects pertaining to cows, sires and dams. AIREML software package was used to analyse the data. The genetic and phenotypic parameters obtained in this study were used to compute direct and correlated responses to selection. Because of the higher heritabilities in first parity, genetic progress was found to be greater when selection was practised on first parity cows as compared to later lactations. It is therefore recommended that older cows in the herd be replaced with improved heifers so as to enhance genetic progress.

• Journal of Animal Science and Technology
• /
• 제47권3호
• /
• pp.397-408
• /
• 2005

This study, consisting of three experiments, was conducted to determine the effects of feeding feather meal (FM), feather meal digest (FMD), L-cystine and methionine hydroxyl analogue (MHA) on taurine content of milk and milk production of Holstein dairy cows. In experiment 1, FM or FMD was supplemented at 0, 1, 3 and 5% of dry matter intake (DMI), respectively. Taurine concentration of 3% FM and 5% FMD treatment were increased by 14% and 220/0, respectively. The 5% FM treatment had a negative effect on milk yield and FM and FMD treatments had no significant or consistent effects on milk fat, protein, lactose, milk urea nitrogen (MUN) and somatic cell count (SCC). In experiment 2, Lcystine or MHA was supplemented at 0, 1, 3, and 5g or ml/d along with 5% FMD, respectively. Milk yield decreased at 3 and 5g or ml Lcystine or MHA supplementation along with 5% FMD. Fat and lactose in milk were not significantly affected by treatments. However, milk protein level increased significantly in the 5 ml HMA with 5% FMD treatment. SCC decreased significantly in 1ml MHA with 5% FMD supplemented treatment but increased in 5g Lcystine with 5% FMD and 5 ml MHA with 5% FMD treatments. Increase of milk taurine concentration of L'cystine with 5% FMD treatments was not significant but those of MHA with 5% FMD treatments were significantly higher than the control. The highest increase of milk taurine concentration was 65% shown in 1 ml MHA with 5% FMD treatment. In experiment 3, 5% FM, 5% FM+3% molasses or 5% FM+3% molasses+l ml MHA was supplemented to the based TMR diet. The molasses treatments (5% FM+3% molasses and 5% FM+3% molasses+l ml MHA) showed significantly higher milk taurine content than the 5% FM treatment. The molasses treatments significantly reduced MUN but increased SCC. It was concluded that FMD is more effective than FM in enriching taurine in milk. Maximum taurine enrichment (65%) in the milk was obtained by supplementation of 5% FMD/DM1+1 ml MHA/d/cow. Molasses supplementation to 5% FM diet increased milk taurine content. However, MHA supplementation in dairy cows increased ruminal escape, gastrointestinal absorption and response of serum methionine.

• Asian-Australasian Journal of Animal Sciences
• /
• 제20권10호
• /
• pp.1525-1538
• /
• 2007

Because of the increasing evidence of potential benefits of conjugated linoleic acid (CLA) on human health, there is a need to investigate its status in commercial dairies and develop feeding strategies to enhance the content and supply of CLA in milk and milk products. A two-year experiment was conducted to study the status of milk fat c-9, t-11 CLA on four selected commercial dairy farms in Utah (two) and Idaho (two), USA. Farms A and C grazed cows on pasture and supplemented with 7.0 kg/cow per day of their respective grain mixes during summer, while conserved forage and grain mix was fed during winter. Farm B fed a total mixed diet all year, with 10% of diet dry matter as fresh cut pasture during summer. Farm D had 1/3 of its cows grazed on pasture and supplemented with a total mixed diet during summer, while the rest were fed a total mixed diet. All cows in Farm D were fed a total mixed diet during winter. Farms A, B, C, and D had on average 80, 400, 150, and 500 milking cows, respectively, with Holstein or its crosses as the major breed. On a year-round basis, Farms A and C produced milk with 60% or more milk fat c-9, t-11 CLA and transvaccenic acid (TVA) contents than Farm B. Similarly, Farm D produced 30% or more c-9, t-11 CLA and TVA in milk than Farm B. Milk fat content of CLA and TVA was 150-200% more during summer compared with winter. Individual cows varied from 0.16 to 2.22% in milk fat c-9, t-11 CLA contents and 89% of the cows had c-9, t-11 CLA contents between 0.3 and 1.0% of milk fat. Individual cow variation was larger on Farms A and C compared with Farm D, with least variation on Farm B. Variation was larger in summer than in winter. The bulk tank milk c-9, t-11 CLA content varied from 0.27 to 1.35% of milk fat. Cows on Farms A and C produced similar or higher amounts of milk fat c-9, t-11 CLA on a daily basis even though their milk yield was lowest among the dairies. Concentration and supplies of c-9, t-11 CLA and TVA were highest from June through September and lowest from February through April, which should be the months for targeting improvement in the content and supply of milk fat c-9, t-11 CLA and TVA.

• 한국초지조사료학회지
• /
• 제26권4호
• /
• pp.207-214
• /
• 2006

본 시험은 2002년 9월부터 2004년 12월까지 충남대학교 농업생명과학대학 내 부속 초지시험포장에서 수행하였다. 공시초종은 청예웅 호밀(Koolgrazer)과 헤어리베치(Common)를 공시하여 주구로 호밀 단파, 호밀 80%+헤어리베치 20% 혼파, 호밀 60%+헤어리베치 40%혼파 및 헤어리베치 단파 등의 4 파종유형과 세구로 수잉기, 출수기, 개화기 및 유숙기 등의 4 수확시기를 두어 분할구배치법 3반복으로 시험하였으며, 얻어진 결과는 다음과 같다. 2년 평f ha당 건물수량은 파종유형과 수확시기에 따라 차이를 보여, 호밀 단파구(9,776kg)가 호밀 80%+헤어리베치 20% 혼파구(9,045kg)나 호밀 60%+헤어리베치 40% 혼파구(8,272kg) 및 헤어리베치 단파구(5,424kg)에 비하여 높은 결과를 나타내었고, 모든 처리구에서 수확시기가 진행됨에 따라 유의적으로 증가되었다(p<0.01). 화학적 성분도 파종유형과 수확시기에 따라 차이를 보여, CP 함량과 DMD는 헤어리베치 단파구에서 높았던 반면에 섬유소물질의 함량은 가장 낮았으나, 호밀 단파구에서는 상반되는 결과를 보였다(p<0.01). 조단백질수량(CPDM)과 가소화건물(DDM)수량은 호밀 80%+헤어리베치 20% 혼파하여 개화기${\sim}$유숙기에 수확하는 것이 가장 높았다.(p<0.01). 이상의 결과로 보아, 호밀이나 혜어리베치의 단파 이용보다는 호밀에 헤어리베치를 20% 정도 혼파하여 개화기${\sim}$유숙기에 수확하는 것이 단위 면적당 수량과 사료가치를 높일 수 있는 한가지 방법이라 하겠다.

• Journal of Nutrition and Health
• /
• 제27권5호
• /
• pp.473-482
• /
• 1994

This study was to compare the bioavailability of calcium from anchovy and tofu to those of calcium from calcium carbonate(CaCO3)as the control diet and non-fat dry milk(NFDM). Rats weighing 50-60g were placed on experimental diets and deionized water at free access for 4 weeks. Diets contained 0.2% calcium from calcium-carbonate, NFDM, anchovy, tofu or 0.5% calcium as obtained were as follows : 1) No significant differences in the apparent absorption of calcium(62.5%-71.0%) were observed in the rats fed four different calcium sources at the level of 0.2% while 0.5% calcium diet group apparently absorbed calcium less efficiently(52.2%). 2) Bone length of tibia and femur was not significantly different among the groups, though 0.5% calcium of control group showed slightly longer length. 3) Tibia fat-free dry weights of 0.2% calcium of NFDM and anchovy diet groups were not significantly different from that of 0.5% calcium of control group. For femurs NFDM, anchovy and tofu groups were similar in their fat-free dry weight to that of 0.5% calcium group. 4) For calcium contents tibia contents tibia from anchovy treated group showed higher value than calcium-carbonate and tofu groups and the value was not significantly different from that of 0.5% calcium group. In femur NFDM, tofu and calcium-carbonate groups were not significantly different in their calcium content but 0.5% calcium group had higher level of calcium than 0.2% calcium groups. 5) The normalized values(NV) show that there was no significant differences in NV among 0.2% CaCO3 anchovy and tofu groups, while NV of NFDM group was significantly lower than that of calcium-carbonate group. NV of 0.5% calcium group was a little more than 50% of those in 0.2% calcium groups. Though the values obtained for the calcium bioavailability were somewhat variable among experimental products, it was demonstrated that anchovy and tofu are as good as NFDM for the dietary calcium provider when calcium intake is at marginal level.

• Asian-Australasian Journal of Animal Sciences
• /
• 제23권3호
• /
• pp.372-378
• /
• 2010

The objective of this study was to investigate the effects of an oral drench of propylene glycol (PG) on milk production, serum metabolites and reproductive performance during the transition period of animals. Twenty-four 2-3 multiparous Holstein cows (average body weight 565 kg, body condition score about 3.6, at the $9^{th}$ month of gestation) were selected, blocked, and then randomly assigned into a PG and a control group. The control and the PG group cows were orally drenched with water or 50 ml sugarcane molasses mixed with 500 ml PG from 7 days pre-partum to 30 days post-partum, respectively. Experimental results indicated that the oral drench PG had no effect on dry matter intake (DMI). The milk yield of the PG group was significantly higher than that of the control group (p<0.05), whereas milk fat content, milk protein and somatic cell counts (SCC) were not significantly different between groups. Concentration of plasma glucose in the PG group was significantly higher than that of the control group (p<0.05). Conversely, the concentrations of non-esterified fatty acids (NEFA), and blood urea nitrogen (BUN) in the PG group were lower than those of the control group (p<0.05). Concentrations of insulin and ketone bodies were not significantly difference between groups. Body condition score (BCS) in the PG group was significantly higher than that of the control group (p<0.05). In reproductive performance there was no difference between groups. The experimental results indicate that supplementation of PG during the transition period of dairy cows can supply energy rapidly, resulting in reduced catabolism of body tissue and increased milk yield.

• Asian-Australasian Journal of Animal Sciences
• /
• 제24권1호
• /
• pp.65-72
• /
• 2011

Twenty-four Holstein dairy cows were used to evaluate the single and combined effects of different levels of crude protein (CP) and monensin treatment during early lactation on blood metabolites, milk yield and digestion of dairy cows. The experiment was designed as a completely randomized block with a $3{\times}2$ factorial arrangement of treatments. The factors were three concentrations of CP supplement (19.5, 21.4, and 23.4% of dry matter) and two levels of monensin (0 and 350 mg per cow per day). The experiment consisted of three phases and each phase was 3 wk in length. Monensin did not affect milk yield, lactose, solids-non-fat (SNF), blood glucose, triglyceride and DMI, but increased blood cholesterol, blood urea nitrogen (BUN), insulin and reduced blood ${\beta}$-hydroxybutyrate (BHBA), milk fat and protein percentage. Monensin premix significantly decreased rumen ammonia, but rumen pH and microbial protein synthesis were not affected by monensin treatment. Increasing dietary CP improved milk and protein production, but did not alter the other components of milk. Digestibility of NDF, ADF, CP were improved by increasing dietary CP. Increasing dietary CP from 19.5 to 21.4% had no significant effect on ruminal ammonia, but increasing CP to 23.4% significantly increased ruminal ammonia. There was a linear relationship between level of crude protein in the diet and volume of urine excretion. Microbial protein synthesis was affected by increasing CP level; in this way maximum protein synthesis was achieved at 23.4% CP.

• Asian-Australasian Journal of Animal Sciences
• /
• 제33권6호
• /
• pp.957-964
• /
• 2020

Objective: An experiment was conducted to determine the effect of partial replacement of soybean meal (SBM) by white lupine seeds (WLS) on milk yield and quality, feed efficiency and rumen fermentation of high-yielding dairy cows. Methods: Thirty multiparous cows of two breeds (20 Holstein and 10 Czech Pied cows) in early mid-lactation received three diets (treatments) in a 3×3 Latin square design with a 28-d period. The dietary treatments were as follows: CON (control total mixed ration with SBM, no WLS), WLS30 (30% of the SBM was replaced, on a dry matter basis, by WLS), and WLS50 (50% of the SBM was replaced by WLS). Results: Feed intake by the cows was not affected (p = 0.331) by the diets. Milk production decreased with increasing proportions of WLS in the diet. Cows fed WLS50 yielded approximately 1 kg/d (p<0.001) less milk than cows fed the CON diet. The proportions of milk fat (p = 0.640), protein (p = 0.507), and lactose (p = 0.709) were not altered by the diet. For milk fat, feeding with WLS50 reduced the proportion of total saturated fatty acids (p<0.001) and increased the proportion of total monounsaturated fatty acids (p<0.001), mainly through oleic acid (p<0.001). No differences were found in feed efficiency, body weight, and blood plasma metabolites between groups. Rumen ammonia-N levels tended (p = 0.087) to increase with increasing proportions of WLS in the diet, whereas no effect of diet on rumen pH was found (p = 0.558). Conclusion: We did not identify the safe range within which raw WLS can efficiently replace SBM in the diet of high-producing dairy cows. In contrast, even partial replacement of SBM by WLS favorably changed the milk fatty acid profile.

• Asian-Australasian Journal of Animal Sciences
• /
• 제33권5호
• /
• pp.825-835
• /
• 2020

Objective: The aim of the present study was to investigate the effect of dietary zinc supplementation of Friesian cows on chemical-nutritional and aromatic properties of Caciocavallo cheese after 7 days (C₇) and 120 days (C₁₂₀) of ripening. Methods: Twenty eight Friesian cows, balanced for parity, milk production and days in milk, were randomly assigned to 2 groups. The control group (CG) was fed with a conventional complete diet, while the experimental group (zinc group, ZG) received a daily zinc supplementation of 60 mg for kg of dry complete feed. During the experimental period, the milk yield was monitored and samples of milk and caciocavallo cheese were collected and analyzed for chemical-nutritional composition and aromatic profile. Results: The enrichment of dairy cows diet with zinc, did not influence milk yield and composition, however a marked reduction of somatic cell count was evidenced. Both in milk and cheese the ZG samples were characterized by a lower concentration of satured fatty acids and an increase in oleic, vaccenic and rumenic acids. The aromatic profile of dairy products was also positively affected by dietary zinc intake, with an increase in concentration of carboxylic acids, esters and lactones. Conclusion: The present results suggest a positive role of dietary zinc intake in improving the quality of bovine milk and related cheese, in particular for the increase in concentration of bioactive fatty acids such as rumenic acid. The changes evidenced in cheese through the analysis of the volatile profile, would be consistent with the development of interesting organoleptic properties, although further evaluations should be performed to confirm the consumer acceptability of these changes.

• Asian-Australasian Journal of Animal Sciences
• /
• 제28권8호
• /
• pp.1095-1104
• /
• 2015

To evaluate the effects of the pelleting and the addition of sodium monensin on production, the chemical and lipid composition of milk and butter physical characteristics, 4 Holstein dairy cows (135 days of lactation) with an average milk production of 14.7 kg/d, were supplemented with a concentrate containing ground canola seeds. The cows were assigned to a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of treatments: i) ground maize, soybean meal, mineral and vitamin supplements, and ground canola seeds (CG); ii) CG concentrate with 31.5 mg of monensin added per kg of dry matter (DM); iii) CG pelleted concentrate; iv) CG concentrate with monensin addition pelleted. There was no difference in milk production and composition. The addition of monensin increased milk concentration of polyunsaturated fatty acids (PUFA), the PUFA/saturated fatty acids (SFA) ratio, and omega 6. The pelleting increased the concentration of monounsaturated fatty acids, the PUFA/SFA ratio, and the omega 6/omega 3 ratio, but decreased the concentration of SFA. The association between pelleting and the addition of monensin increased the concentration of conjugated linoleic acids by 46.9%. The physical characteristics of butter were not affected by the evaluated diets. We concluded that the concentrate with 31.5 mg of monensin added per kg DM basis combined with the pelleting improves the lipid composition of milk from Holstein cows that are on pasture and supplemented with ground canola seeds, without changing the production, milk composition, and spreadability of butter.