Milk Solids-not-fat Research Articles

Morphometric characterization of udder and teat of Jennies

The present study was conducted in eight districts of Marathwada region, Maharashtra, India. A pre-survey was carried to find the maximum available population of donkeys in the respective area. Two hundred two (202) female donkeys were selected for the study. The data was collected based on morphometry of udder, teat, physiological status, pregnancy, lactation, and milk composition. Udder traits such as udder length, udder depth, udder width, udder circumference and teat traits such as teat length and teat diameter were found highly significant in lactating Jennies when compared with dry and pregnant females. The milk composition parameters were milk fat (MF), milk protein (MP), milk solid not fat (MSNF), total solid (TS), odour (O) and test (T): 1.31±0.08, 1±0.01, 6.93±0.03, 8.31±0.09% and 4593±120 per ml, respectively, for overall lactating jennet population.

Quantitative Associations between Season, Month, and Temperature-Humidity Index with Milk Yield, Composition, Somatic Cell Counts, and Microbial Load: A Comprehensive Study across Ten Dairy Farms over an Annual Cycle.

This current study addresses the knowledge gap regarding the influence of seasons, months, and THI on milk yield, composition, somatic cell counts (SCC), and total bacterial counts (TBC) of dairy farms in northeastern regions of Iran. For this purpose, ten dairy herds were randomly chosen, and daily milk production records were obtained. Milk samples were systematically collected from individual herds upon delivery to the dairy processing facility for subsequent analysis, including fat, protein, solids-not-fat (SNF), pH, SCC, and TBC. The effects of seasons, months, and THI on milk yield, composition, SCC, and TBC were assessed using an analysis of variance. To account for these effects, a mixed-effects model was utilized with a restricted maximum likelihood approach, treating month and THI as fixed factors. Our investigation revealed noteworthy correlations between key milk parameters and seasonal, monthly, and THI variations. Winter showed the highest milk yield, fat, protein, SNF, and pH (p < 0.01), whereas both SCC and TBC reached their lowest values in winter (p < 0.01). The highest values for milk yield, fat, and pH were recorded in January (p < 0.01), while the highest protein and SNF levels were observed in March (p < 0.01). December marked the lowest SCC and TBC values (p < 0.01). Across the THI spectrum, spanning from -3.6 to 37.7, distinct trends were evident. Quadratic regression models accounted for 34.59%, 21.33%, 4.78%, 20.22%, 1.34%, 15.42%, and 13.16% of the variance in milk yield, fat, protein, SNF, pH, SCC, and TBC, respectively. In conclusion, our findings underscore the significant impact of THI on milk production, composition, SCC, and TBC, offering valuable insights for dairy management strategies. In the face of persistent challenges posed by climate change, these results provide crucial guidance for enhancing production efficiency and upholding milk quality standards.

Effect of Protein Concentrates and Isolates on the Rheological, Structural, Thermal and Sensory Properties of Ice Cream

The possibility of using protein concentrates and isolates instead of milk solids-not-fat (MSNF) in the production of ice cream with a high mass fraction of milk fat (12%) and increased mass fraction of protein was investigated and justified in this article. The ice cream samples with use of milk protein concentrates (MPC), whey protein concentrates (WPC), milk protein isolates (MPI) and native whey protein isolates (NWPI) were made according to classical technology. Ice cream samples were analyzed by their quality indices. Viscosity and texture of samples were studied by the rheological methods; the overrun was calculated. The microstructural properties, such as dispersion of ice crystals and air bubbles were investigated by the light microscopy. The sensorial properties were analyzed by 6 certified panelists. The reduction in viscosity by 9-74% with use of MPC, WPC and MPI and the increase by 96% with use of NWPI were noted. It was found that replacement of MSNF reduced the overrun by 36-67%. Study of microstructure showed that with use of protein isolates, mean size of ice crystals was reduced and with use of protein concentrates was increased. The increasing in mean size of air bubbles with use of NWPI was established. The studied textural parameters were increased with use MPC and MPI. The hardness and adhesiveness with use of NWPI were increased. The sensorial properties of samples with replacement of MSNF were not worse than with use of MSNF. It has been established that the replacement of MSNF with concentrates and isolates of milk and whey proteins can be an effective way to increasing the protein content in ice cream while maintaining or improving its sensory properties.

Effect of season and stage of lactation on milk components in Purnathadi buffaloes

The present study was designed to observe the effect of season and stage of lactation on milk components of Purnathadi buffaloes. Total 346 milk samples were collected, from three different seasons (winter, summer and rainy) and stage of lactation (early, mid and late) for the study. Overall milk fat, protein, lactose, solid not fat (SNF) and total solids (TS) were observed as 8.44±0.07, 3.99±0.02, 3.96±0.02, 8.78±0.04, and 17.23±0.08% respectively. There was significantly higher fat and total solids percent during winter (9.01±0.23 and 17.62±0.26% respectively) and lower during summer (8.25±0.14 and 16.73±0.14% respectively) season, but milk SNF percent was significantly higher during rainy (9.00±0.04%) and lower during summer (8.48±0.05%). Stage of lactation had also significant effect on milk components; milk fat, protein, SNF, and TS percent increased significantly with the advancement of lactation stage, whereas milk lactose was nonsignificant. Milk fat during early, mid and late lactation was 7.43±0.10, 8.40±0.07 and 8.79±0.12%; protein was 3.83±0.06, 3.94±0.02 and 4.06±0.02%; SNF was 8.36±0.14, 8.70±0.04 and 8.96±0.05% and TS was 15.61±0.17, 17.10±0.08 and 17.75±0.12%, respectively. Thus, results of the present investigation indicated that season and stage of lactation affect certain milk components in Purnathadi buffaloes and could be minimized by better farm management practices.

Effects of Environmental Temperature and Humidity on Milk Composition, Microbial Load, and Somatic Cells in Milk of Holstein Dairy Cows in the Northeast Regions of Iran.

Simple SummaryLivestock performance is influenced by different elements due to the complex interactions between the individual animals and environmental conditions such as temperature and humidity. Hence, the influence of environmental temperature and humidity on milk production quality parameters needs to be investigated. The objective of this study is to elucidate the effect of environmental temperature and humidity on milk composition, microbial load, and somatic cells in the milk of Holstein dairy cows. Our findings reveal that, when temperature increased from 6.2 °C to 31.3 °C, the milk protein, fat, solids-not-fat (SNF), and somatic cell count (SCC) significantly decreased. In contrast, the microbial count in milk significantly increased, by approximately 13.7%. When humidity increased from 54% to 82%, the milk protein, fat, SNF, and SCC significantly increased. However, under the same increase in humidity, the microbial count in milk significantly decreased, by approximately 16.3%. The results indicate that there exists a correlation between different months of the year, temperature, and humidity of the environment, in terms of milk components and somatic cells. Our findings reveal that the optimum performance, in terms of milk composition, occurred in the first quarter of the year, while milk quality decreased as temperature increased and humidity decreased.The present study aims to examine the relationships between temperature and humidity and milk composition, microbial load, and somatic cells in the milk of Holstein dairy cows. For this purpose, the temperature–humidity index, ambient temperature, and relative humidity data were obtained from the nearest weather stations. Production data were obtained from four dairy farms in Golestan province, Iran, collected from 2016 to 2021. The traits investigated were protein, fat, solids-not-fat (SNF), microbial load, and somatic cell count (SCC) in milk. The effects of the environmental temperature, humidity, month, and season on the milk composition, microbial load, and somatic cells were analyzed through analysis of variance. The effects of environmental temperature, humidity, month, and season on the milk composition, microbial load, and somatic cell composition were analyzed using a mixed procedure with a restricted maximum likelihood model. Although our findings revealed that there were significant differences in fat, protein, SNF, and SCC among the different months of the year (p < 0.01), no significant difference was observed in the total microbial count in milk. Environmental temperature presented significant impacts on fat, protein, SNF, SCC, and total microbial count within various temperature ranges (p < 0.01). When the temperature increased from 6.2 °C to 31.3 °C, the milk protein, fat, SNF, and somatic cell count significantly decreased, by approximately 4.09%, 5.75%, 1.31%, and 16.8%, respectively; meanwhile, the microbial count in milk significantly increased, by approximately 13.7%. Humidity showed an influence on fat, protein, non-fat solids, somatic cells, and total microbial count within different temperature ranges (p < 0.01). When the humidity increased from 54% to 82%, the milk protein, fat, SNF, and SCC significantly increased, by approximately 3.61%, 4.84%, 1.06%, and 10.2%, respectively; meanwhile, the microbial count in milk significantly decreased, by approximately 16.3%. The results demonstrate that there is a negative correlation between different months of the year, temperature, and the humidity of the environment, in terms of milk components and SCC. Our findings demonstrate that the optimum performance, in terms of milk composition, occurred in the first quarter of the year. As temperature increases and humidity decreases, milk quality decreases. Therefore, the adverse effects of environmental conditions on agricultural profits are not negligible, and strategies to better deal with the negative environmental effects are needed in order to improve milk quality in dairy cows.

Dairy ingredients replaced with vegan alternatives: valorisation of ice cream

SummaryWith growing concerns of food fortification, dairy ingredient alternatives and waste management have risen the need for food manufacturers to review their recipes. Hence, this study was aimed to extract watermelon seed protein concentrates (WSPC) with ultrasonication and develop vegan ice cream with improved functional properties. Coconut fat and coconut milk were used as fat replacer and total solids source along with extract of WSPC substituting milk solids‐not‐fat (MSNF). Various functional properties of WSPC were assessed. Rheological, structural and sensory quality of vegan ice cream were comparable with standard dairy ice cream formulation. Melting resistance, viscosity and textural hardness were increased with increasing concentration of WSPC and found maximum in IC4 except overrun which was highest (62.02 ± 0.16) in IC0V. Whereas, protein, total solids and total soluble solids were highest in IC4 in contrast to fat and pH which was maximum in IC0D (9.96 ± 0.016) and IC0V (6.82 ± 0.01), respectively. All treatments were found acceptable but highly satisfactory sample, concerning sensory acceptability, was IC2 with 10% WSPC.

Effects of Bovine Pichia kudriavzevii T7, Candida glabrata B14, and Lactobacillus plantarum Y9 on Milk Production, Quality and Digestive Tract Microbiome in Dairy Cows.

Microbial administration has been used successfully to improve host health. However, the positive effects of endogenous microbials are still underexplored. This study investigated the effects of bovine Lactic acid bacteria and yeast on the milk production, quality and digestive tract microbiome of dairy cows. Lactobacillus plantarum Y9, Pichia kudriavzevii T7 and Candida glabrata B14 isolated from high-yielding dairy cows were selected to feed low-yielding Holstein cows. Pichia kudriavzevii T7 could significantly increase milk yield, meanwhile, Pichia kudriavzevii T7 and Candida glabrata B14 could obviously reduce the number of somatic cell counts (SCC). However, slight differences were found in milk fat, protein, lactose and SNF (solids not fat) percentage. High throughput sequencing showed that the dominant bacteria were Prevotella and Ruminococcaceae in rumen and feces, respectively, and the dominant fungi were Penicillium, Aspergillus and Trichoderma in both samples, before and after feeding the microbial addition. Nonetheless, microbial addition changed the abundance and structure of the microbiome in the digestive tract. Our data showed bovine yeast and LAB were beneficial for improving performance and regulating the microbial structure of dairy cows. This study was expected to enrich the knowledge of the digestive tract microbiome in dairy cows and provide a feasible strategy for the further utilization of bovine microorganisms.

Evaluation of whey protein concentrate as a functional ingredient on quality of goat milk rasogolla - an Indian dessert

In the literature, a variety of dairy products are made from goat milk; however, information related to the manufacture of rasogolla from goat milk is very scant. During preliminary trials, it was observed that chhena prepared from goat milk was not suitable for the preparation of rasogolla because it has a very soft and sticky body that is difficult to handle. Therefore, this investigation was conducted to formulate an acceptable quality goat milk rasogolla using whey protein concentrate (WPC) as a functional ingredient. Chhena (also known as Indian cottage cheese, a heat- and acid-coagulated indigenous dairy product) was prepared from fresh Surati goat milk (3.5% fat/8.5% milk solids-not-fat (MSNF). Twelve batches of rasogolla were prepared from chhena coagulated at three temperatures viz. 75, 80 and 85⁰C containing WPC at 4 levels (i.e., 0, 0.25, 0.50 and 0.75% w/w of milk). Rasogolla prepared from chhena containing 0.50% WPC in milk and coagulated at 80°C was preferred the most with respect to all the sensory attributes evaluated. It had significantly (P&lt;0.05) highest sucrose content, i.e., 35.73% and a higher sugar absorption ratio, i.e., 2.63, compared to all the other experimental samples. The composition of drained samples of goat milk rasogolla was as follows: moisture 50.07%; protein 7.04%; fat 6.44%; ash 0.45% and sucrose 35.73%. The pH was 6.34 and acidity was 0.76% lactic acid. Based on the results obtained in this study, a method was developed for the preparation of acceptable quality goat milk chhena and rasogolla.

Single and combined effects of CSN1S1 and CSN2-casein genes on Awassi sheep milk quantity and quality.

Background and Aim:Milk produced from Awassi sheep is of high nutritive value; its production is relatively low in Awassi sheep, so the genetic improvement programs targeted milk production and its components are of high importance, especially when using genes that have an important signal to milk traits. This study was aimed at assessing the influence of alpha S1 (CSN1S1) and beta-casein (CSN2) genes genotypes interaction on Awassi ewes milk productivity.Materials and Methods:A total number of 391 milk yield and its composition records (taken through five consecutive years, 2007-2011) of 167 ewes were utilized for this study. DNA samples were extracted from the ewe’s blood samples, then the polymerase chain reaction products of alpha S1 (CSN1S1) and beta-casein (CSN2) genes were sequenced. The obtained sequences were analyzed; thereafter, the detected variants were tested for their possible association with milk traits.Results:The CSN1S1 and CSN2 variants allelic frequencies were 0.85 and 0.15, and 0.95 and 0.05, respectively. Lactose and solid not fat (SNF) % were associated with TC CSN1S1 genotypes. No association was found among CSN1S1 polymorphic genotypes with milk production, lactose, and SNF % were associated with TC CSN1S1 genotypes. Ewes of CSN2 AC genotype showed higher milk production traits, while no association was found between milk composition traits and CNS2 genotypes. Nevertheless, CSN1S1*CSN2 interaction showed the highest SNF, fat percentages, and milk production.Conclusion:The substantial interaction effects between CSN1S1×CSN2 genes were significantly affected the amount of milk, fat, and SNF% produced. The detected variants should be included in the breeding programs of Awassi sheep that are designed for improving their milk quantity and quality.

Evaluation of Impact of Chelated Mineral Mixture Formulation Supplementation on Milk Quantity and Milk Quality Parameters in Lactating Dairy Cows under Field Conditions

Background: The primary aim of the present study is to evaluate the effect of chelated organic mineral mixture “HimChelate” (Developed by Himalaya Wellness Company) on milk production, fat percentage, solids not fat (SNF) and milk somatic cell counts in lactating dairy cows. Methods: A total of eight lactating dairy cows were randomly selected in one group (G) supplemented with HimChelate mixed with concentrate feed and water at a dose of 30 g/day/cow. The cows were used as their controls and thus, allocated to a control pretreatment period (baseline; 7 days), followed by a treatment period (30 days) and after the treatment period (7 days). The impact of HimChelate supplementation on milk production and quality parameters viz, fat and SNF percentages were before supplementation (baseline), during the supplementation period of HimChelate daily up to 4 weeksand after supplementation of HimChelate (1 week) were accessed to evaluate the efficacy of HimChelate. Result: The mean milk yield in G on the baseline and during the treatment period, i.e., weeks 1, 2, 3 and 4, was 10.64±1.34 and 10.72±1.36, 10.76±1.35, 10.79±1.37 and 10.73±1.40, respectively. The sum milk yield was increased moderately in G during the treatment period compared with that on the baseline throughout the treatment period, i.e., 0.58 L (week 1), 0.93 L (week 2), 1.20 L (week 3) and 0.68 L (week 4). The impact of HimChelate on assessment parameters, such as milk yield, fat and SNF in dairy cows showed that mean milk yield (L) was increased by 1.03% following supplementation of HimChelate at 30 g (G) once daily per cow, respectively. Conversely, fat and SNF percentages were increased by 4.41% and 0.25% following the supplementation of HimChelate at 30 g(G). The supplementation of HimChelate 30 g once daily caused a slight reduction in milk somatic cell count (SCC) as early as day 3 (5100000 cells/mL). Conversely, the major reduction in milk SCC count was observed from day 9, i.e., 900000 cells/mL and maintained milk SCC of 300000 cells/mL from days 12 to 21. The findings of present research investigation depicted that the supplementation of HimChelate at the dose of 30 g/day/cow was better in terms of augmentation of milk production and improvement of milk quality parameters.

Prediction of Lambs Growth From Milk Production and Its Composition in Awassi Sheep and Description of Growth Curve of Non-Linear Function

This study was undertaken at the Ruminant’s Research Station, Office of Agricultural Research/Ministry of Agriculture (20 km west of Baghdad). 102 ewes were used in this study from 1/1/2020- 1/10/2021 to study prediction of lambs growth from milk production and its composition in Awassi sheep and description of growth cure of non–linear function. Simple regression was used to examine relationship between growth traits such as gain, weaning weight, weight at 6 months of age and milk production and its composition. Regression of weaning weight was positive and highly significant (P≤ 0.01) with daily milk yield (DMY) and significant (P≤0.05) with dam’s milk protein percentage (MPP), Analysis of regression also showed significant positive increasing (p≤ 0.05) in lambs' weight at six months of age with increasing of DMY and MPP, where coefficient of regression (CR) amount to 5.006 kg/kg and 0.663 kg/% respectively. Results showed that CR of gain from birth to weaning was highly significant with dam’s DMY, whereas was significant with MPP. Both DMY and MPP had significant and positive relationship with gain between birth weight and weight at six months, where amount of CR was 4.859 kg/kg and 0.619 kg/% with determination coefficient (R2) amount to 0.31 and 0.19 sequentially. Also, positive and significant regression was noticed for gain from birth to 6 months with MPP and milk Solids Not-Fat(SNF) percentages. Exponential functions also were used according to analysis of non-linear regression with calculated R2 for growth in Awassi lambs. Results showed that relationship which derives from regression weight at 6 months on weight at weaning according to equation WT6^=a+b WWT2 is considered the best because increasing value of R2 which was 0.69. we conclude, possibility prediction in lamb’s growth from birth to six months depend on DMY and MPP, also dependence non-linear functions gave an important results to describe growth curves between weaning to 6 months.

Genome-Wide Association Studies in Indian Buffalo Revealed Genomic Regions for Lactation and Fertility.

Murrah breed of buffalo is an excellent dairy germplasm known for its superior milk quality in terms of milk fat and solids-not-fat (SNF); however, it is often reported that Indian buffaloes had lower lactation and fertility potential compared to the non-native cattle of the country. Recent techniques, particularly the genome-wide association studies (GWAS), to identify genomic variations associated with lactation and fertility traits offer prospects for systematic improvement of buffalo. DNA samples were sequenced using the double-digestion restriction-associated DNA (RAD) tag genotyping-by-sequencing. The bioinformatics pipeline was standardized to call the variants, and single-nucleotide polymorphisms (SNPs) qualifying the stringent quality check measures were retained for GWAS. Over 38,000 SNPs were used to perform GWAS on the first two principal components of test-day records of milk yields, fat percentages, and SNF percentages, separately. GWAS was also performed on 305 days’ milk yield; lactation persistency was estimated through the rate of decline after attaining the peak yield method, along with three other standard methods; and breeding efficiency, post-partum breeding interval, and age at sexual maturity were considered fertility traits. Significant association of SNPs was observed for the first principal component, explaining the maximum proportion of variation in milk yield. Furthermore, some potential genomic regions were identified to have a potential role in regulating milk yield and fertility in Murrah. Identification of such genomic regions shall help in carrying out an early selection of high-yielding persistent Murrah buffaloes and, in the long run, would be helpful in shaping their future genetic improvement programs.

Controlling the hardness of ice cream, gelato and similar frozen desserts

Controlling the hardness of ice cream, gelato and similar frozen desserts

Seasonal variation in milk yield, fat and SNF content of Murrah crossbred buffalo in mid-western Terai region of Nepal

A research was done during July 2016 to June 2017 for a period of one year at Baijanath Rural Municipality, Banke district of mid-western terai region of Nepal to analyze the seasonal variation in average daily milk yield (DMY), standard 305 days milk yield (SMY), fat percent and solid-not-fat (SNF) percent in the milk of crossbred Murrah buffaloes. A total of 1086 milk sample was purposively collected from 235 lactating crossbred Murrah buffaloes of early (first and second) parity and were analyzed for major quality traits of milk covering four seasons- spring (February to April), summer (May to July), autumn (August to October), and winter (November to January). Results revealed that season had significant influence on DMY (p&lt;0.05), SMY (p&lt;0.01), fat (p&lt;0.01) and SNF (p&lt;0.01) content of crossbred Murrah buffaloes. Accordingly, highest DMY and SMY was recorded for the buffaloes calved in spring season with highest fat and SNF content during summer and spring season, respectively. Thus, results of this study reflected a scientific fact about wider variation in milk yield, fat and SNF contents in Murrah buffaloes with the significant effect of season. This information could be useful in recognizing the importance of synchronizing calving dates during spring season for higher production and productivity in order to maintain the quality aspects of milk, such as fat and SNF content. Further investigation is, however, required regarding genetic parameters determination of these traits covering wider population in the region.

Effects of Soymilk and Milk Solid not Fat on Soy Ice Cream Quality

Soy ice cream is a vegan friendly frozen dessert prepared using soymilk as the major ingredient. Nine formulations of soy ice cream were prepared with varying levels of soymilk (0-100%) and milk solid not fat (MSNF) (10-12%). From sensory evaluation, 50% soymilk and 12% MSNF resulted the best ice cream of all the formulations. From response study, it was found that the overrun was positively affected but melting rate was negatively affected by soymilk whereas both the overrun and melting rate were negatively affected by MSNF and the formulation of 100% soymilk and 10% MSNF was found to be the best optimized. Chemical analysis of the best product (50% soymilk and 12% MSNF) showed 64% moisture, 10% fat, 5.6% protein, 18.9% total sugar and 0.4% ash. Hence, soy ice cream can be prepared by using milk (50%), soymilk (50%) and MSNF (12%) with physical, chemical and sensory qualities similar to that of plain ice cream.

Impact of environmental factors on milk constituents and yield traits in Murrah buffaloes

The present study was carried out to analyse milk constituents and yield traits using 1,582 first lactation monthly test day records of 224 Murrah buffaloes, calved between 2006 and 2014. The overall least-squares means of monthly test day milk constituent traits, viz. fat, protein, lactose, solids-not-fat (SNF) and total solids (TS) were 7.96 ±0.07, 3.86±0.02, 5.63±0.02, 9.97±0.01 and 17.75±0.07%, respectively. The overall least-squares means ofmonthly test day milk constituent yield traits, viz. milk yield, fat yield, protein yield, lactose yield, SNF yield and TS yield were 6.95±0.15 kg, 549.76±12.97 g, 269.17±6.12 g, 392.52±8.65 g, 681.02±14.97 g and 1231.00±27.46 g, respectively. The estimates of milk constituent traits were found higher in autumn and lower in summer season, except SNF (%) that was found higher in rainy season. All the yield traits were found higher in winter and autumnseason and lower in rainy season. Milk protein (%) was significantly higher during early stage (&lt;90 days) and decreased along with stage of lactation. On the other hand, milk lactose (%) was minimum during early stage of lactation and increased thereafter. All the yield traits were significantly higher during early stage and decreased with the stage of lactation. All the milk constituent traits were higher in buffaloes calved up to the age of 51 months; whereas, buffaloes calved after 51 months of age had higher yield traits. Phenotypic correlations revealed that, milk fat, lactose and TS per cent had very low and negative correlation with monthly test day milk yield. The milk fat (%) had very high and positive correlation with TS (%), indicating that, buffaloes with higher fat content may be selected for higher TS content in milk. Data on variation of milk constituent and yield traits over the years, seasons, stages of lactation and age of buffaloes can be utilized to improve quality as well as quantity of milk in breed improvement programmes.

Correlation between in vitro activity of milk leukocytes with milk constituents in high yielding crossbred cows

The relationship between the in vitro activity of milk leukocytes and milk constituents were studied in 48 high yielding clinically healthy crossbred cows. Milk somatic cell counts (SCC) was negatively correlated with milk lactose, total soid and solid not fat (SNF) content. Milk neutrophils were positively correlated with protein and Cu content and negatively correlated with fat content in milk. However milk lymphocytes were positively correlated with milk fat content and negatively correlated with protein content. Milk macrophages were positively correlated with milk SNF and total solid content. Milk lymphocyte blastogenic response (SI) was significantly positively correlated with milk protein, fat percentage and copper content and negatively correlated with milk lactose, milk total solids, SNF and zinc content. PI of milk neutrophils was positively correlated with zinc content and milk fat percentage and negatively correlated with milk total solid and SNF content. PI of milk macrophages was positively correlated with milk fat content. In the present investigation, immuno-potentiative role of various milk constituents such as milk protein, copper and zinc content on in vitro leukocyte activity was established.

Effect of pre- and post-partum dietary crude protein level on the performance of ewes and their lambs

In a block randomized design, fifty-one Barki ewes weighing 38.0kg in average and 2–4 years old, were used to study the effect of pre- and post-lambing dietary crude protein level (CP) of concentrates on the milk yield, milk composition and weight of ewes, and performance of their lambs. The treatments comprised supplementary concentrate containing (g/kg dry matter (DM)): (1) 110 CP (low), (2) 130 CP (medium) and (3) 150 CP (high), while Egyptian berseem hay (Trifiolium alexandrinum) was the basal diet. Ewes were weighed individually biweekly, and the number of lambs dropped and nursed by ewes was recorded within 24h after birth and biweekly subsequently. New-born lambs were left to suckle their dams freely, except for the period when milk yield was recorded by weighing lambs before and after suckling. Milk yield was estimated once a week. Ewes were fed the experimental diets during the last two months of pregnancy and throughout the lactation period. Ewes fed 110g CP/kg DM attained peak of milk yield earlier than those fed 130 and 150g CP/kg DM. Total milk yield, milk fat and milk total solids, and weaning weight, average daily gain and relative growth rate of lambs were higher (P<0.05) for ewes fed medium and high protein levels compared to those fed low protein level. Suckled milk was affected by protein level (P<0.05); the rank order was: 110CP<130CP<150CP. Milk protein and extractable milk were higher (P<0.05) for high protein level compared to low protein level but solids-not-fat (SNF) and lamb birth weight were not affected (P>0.05) by protein level. Lamb sex, and parity and weight at lambing of ewes had no effect (P>0.05) on suckled milk, extractable milk and milk yield. Whereas lamb sex and parity of ewe had no effect (P>0.05) on milk composition, ewe lambing weight affected (P<0.05) milk fat and SNF but not milk protein and total solids (P>0.05). Weights of ewes during gestation, after lambing (post-partum weight loss) and during lactation were not affected (P>0.05) by protein level, except at the 3rd month of lactation. Lamb sex, parity and lambing weight had pronounced (P<0.05) effects on lamb birth weight and weaning weight. It is concluded that 150g CP/kg DM level pre- and post-partum could be used for improved performance of ewes and their lambs while parity and weight of ewe at lambing should also be given consideration.

USING WHEY PROTEIN ISOLATE AS A SUBSTITUTE OF MILK SOLID NOT FAT ON CHEMICAL AND PHYSICO-CHEMICAL PROPERTIES OF ICE CREAM

Effect of whey protein isolate (WPI) as a partial substitution of milk solids not fat (MSNF) in ice cream formula was investigated by replacing 1, 2, 3 and 4% of mix solid not fat. Mixes and resultant ice cream samples were evaluated for their chemical, physico-chemical, as well as the sensory quality attributes. There was no remarkable effect of adding WPI as partial substitution of skim milk powder (SMP) on total solids or fat percentages, while total protein, ash, and lactose content were significantly affected. Specific gravity was affected with the ratio of substitution in both mixes and resultant ice cream and therefore the weight per gallon and overrun percent was significantly changed in the samples. Also, freezing point of resultant ice cream was affected by implementing WPI in ice cream mix. However, the ice cream became smoother and highly acceptable by replacing MSNF with WPI up to 3%. From the data obtained, it could be recommended that ice cream can be produced with high quality by substituting MSNF with WPI up to 3%.

Effect of season, genotype and lactation on milk yield and composition of local and crossbred dairy cows reared under different feed base region

A total of 160 cows, 10 cows in each of native (local cow) and crossbred (local × Holstein Friesian) origins differing in lactation were used in 2×2×2×2 factorial experiment using Randomized Block Design (RBD) to evaluate milk yield and composition of cows considering regions (good &amp; poor feed base region), seasons (dry: Nov.–Feb. 2009 &amp; wet: Jun.–Oct. 2009), genotypes and lactation. A “good and/or poor feed base” region was classified based on the availability of quantity and quality roughages throughout the year. The study revealed that the daily milk yield and 4% FCM of cows under good feed base condition were 6.76 and 6.49 kg, respectively and under poor feed base condition were 3.67 and 3.31 kg, respectively. Feed base region did not affect on milk fat and it was observed that the milk protein, lactose, solids-not-fat (SNF), minerals and total solids under good feed base condition were 37.9, 54.9, 100.9, 6.3 and 140.6 g/kg, respectively, whereas, under poor feed base condition the values were 36.3, 52.9, 98.0, 6.1 and 135.2 g/kg, respectively. Season did not affect milk yield and composition except minerals (6.5 g/kg vs. 5.9 g/kg). Genotypes significantly (p?0.01) influenced daily milk yield, the milk protein and minerals. Lactation did not affect milk yield and the milk protein, but influenced the fat, lactose, SNF, minerals and total solids. The interaction of feed base regions and seasons significantly (p?0.01) influenced milk yield and the milk fat and SNF. The milk protein and lactose was influenced by the interaction of feed bases region, seasons and lactation. Milk yield negatively correlated with fat per cent. The percentage of fat significantly (p?0.01) correlated with protein, lactose, SNF, and minerals %. The percentage protein correlated with lactose, SNF and minerals. Lactose % significantly (p?0.01) correlated with SNF%. It may be concluded that milk yield and composition depends on feed base region, genotype and lactation of cows. Season did not influence milk yield and the composition. Milk yield negatively correlated with the percentage of fat, protein, lactose, SNF and milk composition strongly correlated with each other.Bangladesh J. of Livestock Res. 19(1-2): 50-65, Jan-Dec 2012