• Animal Bioscience
• /
• v.34 no.1
• /
• pp.36-47
• /
• 2021

Objective: This study determined the optimal ratio of whole plant corn silage (WPCS) to corn stover (stems+leaves) silage (CSS) (WPCS:CSS) to reach the greatest profit of dairy farmers and evaluated its consequences with corn available for other purposes, enteric methane production and milk nitrogen efficiency (MNE) at varying milk production levels. Methods: An optimization model was developed. Chemical composition, rumen undegradable protein and metabolizable energy (ME) of WPCS and CSS from 4 cultivars were determined to provide data for the model. Results: At production levels of 0, 10, 20, and 30 kg milk/cow/d, the WPCS:CSS to maximize the profit of dairy farmers was 16:84, 22:78, 44:56, and 88:12, respectively, and the land area needed to grow corn plants was 4.5, 31.4, 33.4, and 30.3 ha, respectively. The amount of corn available (ton DM/ha/yr) for other purposes saved from this land area decreased with higher producing cows. However, compared with high producing cows (30 kg/d milk), more low producing cows (10 kg/d milk) and more land area to grow corn and soybeans was needed to produce the same total amount of milk. Extra land is available to grow corn for a higher milk production, leading to more corn available for other purposes. Increasing ME content of CSS decreased the land area needed, increased the profit of dairy farms and provided more corn available for other purposes. At the optimal WPCS:CSS, MNE and enteric methane production was greater, but methane production per kg milk was lower, for high producing cows. Conclusion: The WPCS:CSS to maximize the profit for dairy farms increases with decreased milk production levels. At a fixed total amount of milk being produced, high producing cows increase corn available for other purposes. At the optimal WPCS:CSS, methane emission intensity is smaller and MNE is greater for high producing cows.

• Journal of Veterinary Clinics
• /
• v.19 no.1
• /
• pp.43-48
• /
• 2002

This study was performed to investigate the effects of recombinant BST formulation treatment on the milk yield, milk components, mastitis, and general cow health condition when the formulations of retinyl palmitate, cholecalciferol and rBST were administered after the peak period of milk production. The milk yields of treatment groups (Group I, II, III and IV) were increased from 21.5% to 29.0% than that of control group. There was significant difference in milk production between treatment group II, IV and control group (P<0.05). However, there was no significant difference in milk production between treatment group I, III and control group (P<0.05). And the addition of retinyl palmitate and cholecalciferol into rBST formulation did not increase the milk yield. The milk of treatment groups with sustained-release rBST did not show significant difference in milk components (milk fat, protein, lactose, and solid not fat). However, there were minor changes, primarily in fat content of milk, during the first few weeks of rBST administration. There was no incidence of clinical mastitis between rBST treatment groups and control group. Addition of high and medium concentration of retinyl palmitate and cholecalciferol into sustained-release rBST formulation was efficient in reduction of somatic cell count in milk. There was great energy deficit in all treatment groups compared with control group during the early study period. Thus, the body condition score of all treatment groups showed lower value than control group. No evidences of metabolic health problems, such as ketosis, milk fever, and downer cow were observed. Incidence of general lameness did not appear on all treatment groups during 140 days of this study.

• Journal of Dairy Science and Biotechnology
• /
• v.42 no.1
• /
• pp.1-8
• /
• 2024

The global dairy industry has faced substantial challenges because of the prolonged coronavirus of 2019 (COVID-19) pandemic since 2020 and the initiation of conflict between the Ukraine and Russia. In 2022, the overall milk production reached 936 million tons, reflecting a modest 1.1% increase in total global production. This indicates below-average growth for the second consecutive year because the supply to major export regions became more challenging owing to a significant increase in costs. In China, India, and Pakistan, total milk production increased markedly by 3.1% (average) because of buffalo milk production. In the near future, global milk production is expected to exhibit an average annual growth rate of 1.5%, exceeding that of other major agricultural products. Notably, the trade flow of dairy products is highly reactive to changes in the trade policy environment. Revisions to existing trade agreements or the introduction of new agreements can significantly impact the demand for dairy products and alter the trade patterns of the industry. Collectively, adaptability and strategic policy responses are critical in shaping the future development of this industry, and industry stakeholders worldwide should remain vigilant and prepare for these challenges.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.12
• /
• pp.1813-1821
• /
• 2002

The aim of this study was to identify useful secondary traits for estimating genetic ability of milk production traits. We investigated the value of using plasma metabolites concentrations. Two hundred and nineteen cattle out of 271 had only milk production traits records (G1), 33 had only metabolites records (G2), and 19 had both milk production traits and metabolites records (G3). Fifty two calves with metabolites records (G2 and G3) were born from 1992 to 1997. Forty three calves (29 females, 14 males) were used from 10 to 90 d of age and the others (3 females, 6 males) from 10 to 60 d of age. A total of 566 records of milk yield, fat yield and protein yield for 240 to 305 d on 238 heads (G1 and G2) were collected The collected blood samples were divided into three age groups: AG1, 10 to 30 d; AG2, 40 to 60 d; and AG3, 70 to 90 d. Heritabilities of milk yield, fat yield and protein yield were $0.45{\pm}0.04$, $0.50{\pm}0.04$ and $0.38{\pm}0.04$, respectively. Heritability of plasma glucose concentration at AG1 was $0.45{\pm}0.08$. Genetic correlations between plasma glucose concentration and milk yield, fat yield and protein yield were -$0.35{\pm}0.28$, $0.64{\pm}0.24$ and $0.36{\pm}0.35$, respectively. When the plasma glucose concentration at AG1 was used to estimate genetic ability of these milk production traits, reliability of milk yield of animals without milk record increased 8.2%, fat yield increased 24.2% and protein yield increased 9.5%. Heritability of plasma total cholesterol concentration at AG3 was $0.83{\pm}0.04$. Genetic correlation between plasma total cholesterol concentration and milk yield, fat yield and protein yield were $0.58{\pm}0.21$, $0.42{\pm}0.20$ and $0.45{\pm}0.22$, respectively. When the plasma total cholesterol concentration at AG3 was using to estimate genetic ability of these milk production traits, reliability of milk yield of animals without milk record increased 19.0%, fat yield increased 9.6%, and protein yield increased 13.5%. The annual genetic gain is in proportion to the reliability of selection. These results show that the plasma metabolite concentrations would be useful for improvement of genetic ability for milk production traits in the genetic improvement in herd of cows, where half of the animals selected are from a herd without its own milk record.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.8
• /
• pp.1105-1116
• /
• 2017

Objective: A meta-analysis was conducted to evaluate the effects of supplemental fat containing saturated free fatty acids (FA) on milk performance of Holstein dairy cows. Methods: A database was developed from 21 studies published between 1991 and 2016 that included 502 dairy cows and a total of 29 to 30 comparisons between dietary treatment and control without fat supplementation. Only saturated free FA (>80% of total FA) was considered as the supplemental fat. Concentration of the supplemental fat was not higher than 3.5% of diet dry matter (DM). Dairy cows were offered total mixed ration, and fed individually. Statistical analysis was conducted using random- or mixed-effects models with Metafor package in R. Results: Sub-group analysis showed that there were no differences in studies between randomized block design and Latin square/crossover design for dry matter intake (DMI) and milk production responses to the supplemental fat (all response variables, $p{\geq}0.344$). The supplemental fat across all studies improved milk yield, milk fat concentration and yield, and milk protein yield by 1.684 kg/d (p<0.001), 0.095 percent unit (p = 0.003), 0.072 kg/d (p<0.001), and 0.036 kg/d (p<0.001), respectively, but tended to decrease milk protein concentration (mean difference = -0.022 percent unit; p = 0.063) while DMI (mean difference = 0.061 kg/d; p = 0.768) remained unchanged. The assessment of heterogeneity suggested that no substantial heterogeneity occurred among all studies for DMI and milk production responses to the supplemental fat (all response variables, $I^2{\leq}24.1%$; $p{\geq}0.166$). Conclusion: The effects of saturated free FA were quantitatively evaluated. Higher milk production and yields of milk fat and protein, with DMI remaining unchanged, indicated that saturated free FA, supplemented at ${\leq}3.5%$ dietary DM from commercially available fat sources, likely improved the efficiency of milk production. Nevertheless, more studies are needed to assess the variation of production responses to different saturated free FA, either C16:0 or C18:0 alone, or in combination with potentially optimal ratio, when supplemented in dairy cow diets.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.2
• /
• pp.187-191
• /
• 2017

Objective: An experiment was conducted to examine the effect of dietary supplementation of dried and ground foliage of black gram (Vigna mungo L.) on feed intake and utilization, and production performance of crossbred lactating cows. Methods: Eighteen lactating crossbred (Bos taurus${\times}$Bos indicus) cows (body weight $330.93{\pm}10.82kg$) at their second and mid lactation (milk yield $6.77{\pm}0.54kg/d$) were randomly divided into three groups of six each in a completely randomized block design. Three supplements were formulated by quantitatively replacing 0, 50, and 100 per cent of dietary wheat bran of concentrate mixture with dried and ground foliage of black gram. The designated supplement was fed to each group with basal diet of rice straw (ad libitum) to meet the requirements for maintenance and milk production. Daily feed intake and milk yield was recorded. A digestion trial was conducted to determine the total tract digestibility of various nutrients. Results: The daily feed intake was increased (p<0.05) with the supplementation of black gram foliage. Although the digestibility of dry matter, organic matter, crude protein, and ether extract did not vary (p>0.05), the fibre digestibility was increased (p<0.05), which ultimately improved (p<0.05) the total digestible nutrients content of composite diet. Although, the average milk yield (kg/animal/d) and composition did not differ (p>0.05) among the groups, milk yield was increased by 10 per cent with total replacement of wheat bran in concentrate mixture with of black gram foliage. The economics of milk production calculated as feed cost per kg milk yield (INR 10.61 vs 7.98) was reduced by complete replacement of wheat bran with black gram foliage. Conclusion: Black gram foliage could be used as complete replacement for wheat bran in concentrate mixture of dairy cows in formulating least cost ration for economic milk production in small holders' animal production.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.3
• /
• pp.352-356
• /
• 2002

One hundred-fifty lactating, multiparous cow at post-peak of lactation were used to examine the effect of dietary yeast supplementation on milk production, milk composition and ruminal fermentation. The cows were randomly allocated to three groups of fifty cows each: a control group fed on a basal diet without yeast supplementation and two groups fed on basal diets supplemented with one of two commercial sources of yeast cultures, given at the rates of 15 g/head/d ($YC_1$) and 50 g/head/d ($YC_2$), respectively, as per manufacturers' recommendation. Daily milk production was recorded for all cows, while milk samples were taken randomly from ten cows per group for two consecutive days at two-week intervals for chemical analysis of the milk. Rumen fluids were also analyzed for ammonia nitrogen and volatile fatty acids. The results indicated that cows consuming diets supplemented with yeast culture tended to decrease their dry matter intake and to increase their milk yield. Cows fed $YC_2$ supplemented diet produced more milk and 4% fat corrected milk than those fed either $YC_1$-supplemented diet or the control. The highest milk fat percentage was obtained in cows fed $YC_2$ supplemented diet while the highest percentages of protein, lactose, total solids and solids not fat were recorded in cows fed $YC_1$. Rumen ammonia nitrogen concentration decreased significantly after yeast culture supplementation. Molar proportion of volatile fatty acids did not change significantly with yeast supplementation.

• Asian-Australasian Journal of Animal Sciences
• /
• v.1 no.4
• /
• pp.201-208
• /
• 1988

Fifty-six lactating Surti buffaloes, fed rice straw, were allocated to seven treatment groups as follows: 1. Straw supplemented with 2% urea (SS) + 1.5kg rice bran (RB) 2. Straw treated with 4% urea in an open stack (TS open) 3. TS open + 1.5 kg RB 4. TS open + 3.0 kg RB 5. TS open + 1.5 kg RB + 3.0 kg Gliricidia (Gl) 6. Straw treated with 4% urea in a closed pit (TS closed) 7. TS closed + 1.5 kg RB + 3.0 kg Gl Milk production, butterfat percentage and liveweight gain of cows and calves were measured and tested with analysis of variance. The results are: - The animals on urea treated straw (group 2) had a higher milk production (p<0.05), higher butterfat production (p<0.05) and less liveweight gain loss (p<0.05) than the animals on urea supplemented straw (group 1). Butterfat percentage also increased by treatment, although not significantly (p>0.05). - Increasing levels of rice bran (groups 3 and 4 compared to 2) increased total milk production and milked quantity of butterfat, while butterfat percentage decreased (p < 0.05). - Milk production increased (p <0.05) with extra rice bran added (group 4 compared to 3), but was not affected (p > 0.05) by Gliricidia addition (group 5 compared to 3). Butterfat percentage dropped with extra rice bran supplement (p <0.05). The lack of response to Gliricidia indicated that protein is not limiting in treated straw, or that Gliricidia protein is partly insoluble. - System of treatment had no effect on milk production (p >0.05), while supplementation with 1.5 kg RB and 3.0 kg Gliricidia increased production and caused a lower butterfat percentage (p <0.05) (groups 2, 5, 6 and 7 compared). A significant (p <0.05) interaction treatment system x supplementation was present. It was concluded, that both treatment and supplementation did affect milk production as well as milk composition. Gliricidia addition gave less effect than rice bran, indicating different requirements for starchy substances in the feed. Treatment of straw does not negatively affect butterfat production, it can increase butterfat production and even butterfat percentage.

• Asian-Australasian Journal of Animal Sciences
• /
• v.8 no.5
• /
• pp.481-487
• /
• 1995

A survey of physical inputs was conducted on the total population of dairy farms supplying milk to the Rewa cooperative dairy company in Fiji. The critical inputs associated with total farm milk production were determined using multiple regression, with analyses being conducted for each of the three identified supplier groups, bulk milk, canned milk and cream. Mean annual milk production per cow averaged 1460 (s.d. = 319), 889 (s.d. = 321) and 800 (s.d. = 451) litres for the bulk milk, canned milk and cream suppliers respectively. Stocking rate averaged 1.37 (s.d. = 1.18) cows per hectare over all farms. Inputs to pasture were universally low and Navua sedge (Cyperus aromaticus) was identified as a major weed. The average amount of supplement fed annually on a grain equivalent basis was 700 (s.d. = 984) kg per cow for bulk milk, 84 (s.d. = 198) kg per cow for canned milk and 146 (s.d. = 542) kg per cow for cream suppliers. The analysis of data from a small group of farms using nitrogen fertiliser indicated that their production levels were higher than the general population. This suggests that there is potential for the Fijian dairy industry to increase milk production through the use of higher inputs to cows and pastures. The regression models relating annual milk production from farms to the two key inputs of number of cows milked and the amount of supplement fed were all significant (p < 0.001). The coefficients of determination for these models ranged from 56.9 to 89.4 percent.

• Asian-Australasian Journal of Animal Sciences
• /
• v.24 no.10
• /
• pp.1372-1376
• /
• 2011

The content of Ca in milk exceeds the typical saturation level of Ca salts, which is necessary for neonate growth. This calcium is distributed between the casein micelles in the colloidal and aqueous phases. Information on the properties of calcium activity in the aqueous phase is limited compared with that on the properties of bound or sequestrated calcium. The objectives of this study were to evaluate the changes in calcium activity in fresh milk using an ion-selective electrode and to assess the relationship between calcium activity and milk production in hot season. Milk samples collected from 10 cows at the National Agricultural Research Center for Kyushu Okinawa Region in June to October (Min-Max: 7.2-$35.2^{\circ}C$, 24.3-100% RH) were analyzed on total calcium concentrations and calcium activity. We observed that the rectal temperature of the cows increased according to elevation of ambient temperature but that the pH of the collected milk ($6.61{\pm}0.01$ (Mean${\pm}$SEM)) was not significantly influenced by rectal and ambient temperature. Total calcium concentrations and calcium activity in fresh milk decreased in July (Min-Max: 21.1-$33.5^{\circ}C$, 48.9-100.0% RH) compared with the values after August (Min-Max: 18.1-$35.0^{\circ}C$, 26.5-96.2% RH) (p<0.05); however, there was no significant correlation between the two parameters. The ratio of calcium activity to total calcium concentration decreased after August compared with the values in June and July (p<0.05). The calcium activity in fresh milk was positively correlated with milk yield (r = 0.45, p<0.01) and negatively correlated with milk lactose content (r = -0.53, p<0.01). These results suggest that the calcium activity in milk could be affected by ambient temperature and might be associated with milking production in hot season.