Feeding and keeping cattle for the use of cultivated pastures

The article provides an analysis of the milk productivity of black-and-white cows when they are included in the BVMC Delta Feeds diet. The analysis of the dynamics of the average daily milk yield revealed the superiority of cows of the experimental group over the control in this indicator by 1.54 kg (8.9%). In the course of the research, an analysis of milk yield by month was carried out to assess the animals by their ability to breed. The use of BVMC Delta Feeds in the rations of cows in the first month of lactation was characterized by an increase in daily milk yield. At the same time, the difference between the groups was 6.0% in favor of the experienced cows. The period from the first to the second lactation month was characterized by an increase in milk yields among the first heifers of all groups. In cows of group 1, this indicator increased by 13.3%, in group 2 – by 9.1%. The period from 4 to 10 months in the first heifers of all experimental groups was characterized by a decrease in milk yields. By the fourth month, the average daily milk yield in the cows of the experimental group reached 21.03 kg, which is 2.5 kg (13.2%) more than in the animals of the control group. The analysis of milk yield by months of lactation when using BVMC Delta Feeds showed that its value in control heifers increased to 622.25 kg before the second month, and in cows of the experimental group up to the third month, reaching 684.33 kg. A decrease in milk productivity due to physiological characteristics is observed in cows of group 1 from the third month, and in cows of group 2 from the fourth month. The decrease in milk yield in the control heifers was 46.4%, and in the experimental heifers 48.2%. An analysis of the data obtained shows that the cows of the experimental group had the highest milk yield both in the first and subsequent months of lactation. Thus, the animals of the control variant were inferior to the experienced peers of the 2nd group in terms of milk yield in the first month by 6.0%, in the third – by 12.5%, in the fifth – by 15.1%, in the tenth – by 6.4%.

The crossbred dairy cattle (CDC) have been gaining popularity in the tropical countries for their increased milk yield within a short period of time because of heterogenic additive gene action. Hence, we aimed to investigate whether genotype, parity, season and their interactions had any effect on average daily milk yield (ADMY) of the CDC in a dairy farm at Chattogram district, Bangladesh, for a period of 3years from January 2016 to December 2019. Total 16,425 retrospective lactation records of 150 multiparous Sahiwal×Friesian1 (Sahiwal=50%, HF=50%), Local×Friesian1 (Local=50%, HF=50%) and Local×Friesian2 (Local=25%, HF=75%) CDC from the first to the third parities (50 for each parity) were collected from the farm records. The generalized linear model and principal component analysis identified substantial impacts of genotype, parity, season and their interactions on ADMY of the CDC. The herd level least squared ADMY was 11.22±0.04kg/days on a 305-days typical lactation period. The Sahiwal×Friesian1 CDC produced 7.2% and 5.5% more milk than the Local×Friesian1 and Local×Friesian2 respectively. The CDC produced maximum milk in the second parity, which was 7.8% and 0.34% more than the first and third parities. Similarly, the highest ADMY was recorded in the spring, which was 10.8%, 7.3% and 6.6% more than the fall, summer and winter respectively. It was concluded that the Sahiwal×Friesian1 crossbred produced maximum milk in the spring season at the second parity while other determinants remained constant. The changing patterns of milk yield in different genotype, parity and seasons provided scientific evidence for improving feeding strategy to optimize herd level milk yield of CDC in the commercial dairy farms under tropical perspective.

June and September measurements of lactation were made using 206 (1976) and 242 (1977) cows ranging from 2 to 10 yr of age from the University of Alberta beef herd representing four beef and dairy-beef breeds and lines. Influences on calf weaning weight investigated were age and breed of dam, sex of calf, and the continuous variables of calf age, calf birth weight, cow winter weight loss, cow post-calving average daily gain, milk yields and constituent yields of butterfat, protein and lactose. Milk and constituent yields had similar relationships to calf weaning weight (r = approximately 0.6). Stepwise regressions involving age and breed of dam accounted for 48 and 45% of the variance in weaning weight. When age and breed of dam were ignored, milk or constituent yields accounted for approximately 40% of weaning weight variance. After removing main effects, milk variables explained from 6.2 to 10.4% of the total variance. A unit increase of 1 kg in average daily milk yield was associated with 7.7 kg increase in weaning weight. Birth weight of calf and cow weight change during lactation had minor effects on calf weaning weight. No significant source of variation in weaning weight was explained by cow winter weight loss. As a significant proportion of the variation in weaning weight is accounted for by milk and constituent yields, selection for increased lactation performance and the introduction of dairy breeds into the breeding program of a beef herd can effect meaningful increases in calf weaning weights.

The influence of the experimental probiotic “Plantarum” on the productive and some exterior-constitutional features of dairy Saanen breed goats was studied. The preparation was developed in the microbiology laboratory of milk and dairy products of the department “Siberian Research Institute for Cheese Making” of the Federal State Budgetary Scientific Institution “Federal Altai Scientific Center of Agrobiotechnology” (FSBSI FASCA). The composition of the preparation includes pure cultures of probiotic strains of lactobacilli and propionic acid bacteria from the “Siberian collection of microorganisms”. The probiotic preparation in liquid form was introduced into concentrated feed (oats). The positive effect of the use of the probiotic “Plantarum” on the average daily milk yield of the experimental groups of fully developed (assessed by the exterior) pregnant female goats was established. A significant increase in milk yield was observed in the second and third groups by 1.66% (p < 0.05) and 3.27% (p < 0.05), respectively. With an increase in the average daily milk yield, the main physical and chemical parameters of milk (mass fraction of fat, mass fraction of protein) of the experimental groups did not decrease. There was a tendency to improve the safety of young animals in the second and third groups with an increase in the probiotic dose. At this stage of the work, the optimal dose with the maximum positive effect of introducing the probiotic preparation into the diet of experimental animals (0.8 ml/kg of body weight per day) was established. In this connection, it is necessary to conduct an additional experiment with an increase in the dose of probiotic administration when feeding it to experimental animals.

Twenty-four Red Sokoto goats were hand milked for 120 days to determine milk flow rate. The does were grouped into three for once, twice and thrice a day milking to determine the effect of milkin g frequency on milk flow rate. The average daily milk yield and milk flow rate was 466.9g and 3.5g/sec, respectively. Milking frequency significantly (P<0.01) influenced milk yield and milk flow rate. The higher the milking frequency, the higher the milk yield, but with a decreasing flow rate. Milk yield and milk flow rate were significantly (P<0.01) and positively correlated (r = 0.88). Both milk yield and flow rate reached their peak at the 4 week of production. The optimum milking frequency for Red Sokoto goat in this study was the twice th daily milking, since there was 52.7% increase in milk yield from once a day, with a marginal 7.9% reduction in milk flow rate.

ABSTRACTThis experimental work was carried out to investigate the relationship among age, body weight, body length, body circumference, body height or body condition score and reproductive performance, (represented in mating period, gestation period, litter size, weaning weight and growth rate till weaning), milk yield and composition for Damascus and Zaraibi goats.Damascus does showed that mating period decreased significantly (P<0.05), while birth weight increased significantly (P<0.05) with aging. Litter size was significantly (P<0.05) lower, while weaning weight was significantly (P<0.05) higher for does aged 3-6 years. However, growth rate till weaning decreased significantly (P<0.05) with increasing does age above 6 years. Average daily milk yield and protein content increased significantly (P<0.05) with increasing age. Mating period was significantly (P<0.05) higher with body weight of 41-50 kg. Litter size decreased significantly (P<0.05), while both birth and weaning weight increased significantly (P<0.05) with increasing body weight more than 40 kg. Average daily milk yield did not significantly affected by body weight and body circumference. The contents of lactose and solids not fat in milk decreased significantly (P<0.05) with increasing body weight over 40 kg. Milk yield increased significantly (P<0.05) with increasing body length. The content of fat, protein, solids not fat and total solids were significantly (P<0.05) higher with body circumference over 100 cm. Mating period decreased significantly (P<0.05), however, birth and weaning weight and growth rate till weaning increased significantly (P<0.05) with increasing body height more than 65 cm. Mating period decreased significantly (P<0.05) with increasing body condition score. Litter size, birth and weaning weight and growth rate till weaning increased significantly (P<0.05) with increasing body condition score up to 4. Milk yield and fat content increased significantly (P<0.05) with increasing body condition score up to 4 and the contents of protein, solids not fat and total solids increased significantly (P<0.05) with increasing body condition score up to 3. While, lactose content was significantly (P<0.05) lower with body condition score 1. With regard to Zaraibi does, mating period, birth and weaning weight and growth rate till weaning were higher significantly (P<0.05) with age 3-6 years. Average daily milk yield and protein content increased significantly (P<0.05) with increasing age, however, lactose content decreased significantly (P<0.05) after 6 years of age. Mating period decreased significantly (P<0.05), while litter size, birth and weaning weight and growth rate till weaning increased significantly (P<0.05) with increasing body weight more than 30 kg. Average daily milk yield and the contents of fat, protein, solids not fat and total solids in milk were significantly (P<0.05) higher in does with body weighed 41-50 kg. Milk yield increased significantly (P<0.05) with increasing body length. Mating period was significantly (P<0.05) lower, while litter size, birth and weaning weight and growth rate till weaning were significantly (P<0.05) higher with body circumference more than 80 cm. While, milk yield and composition were not significantly affected by body circumference. Mating period decreased significantly (P<0.05), however, birth and weaning weight and growth rate till weaning increased significantly (P<0.05) with increasing body height more than 55 cm. Milk yield increased significantly (P<0.05) with increasing body height more than 60 cm. However, the contents of fat, lactose, solids not fat and total solids in milk decreased significantly (P<0.05) with increasing body height more than 55 cm. Mating period decreased significantly (P<0.05) with increasing body condition score. Litter size, birth and weaning weight and growth rate till weaning, milk yield and the contents of protein, lactose, solids not fat and total solids in milk increased significantly (P<0.05) with increasing body condition score up to 4. While, fat content increased significantly (P<0.05) with increasing body condition score up to 3.

A total of 439, 436 and 437 records of average daily milk yield (ADMY), milk yield after weaning (MYAW) and total milk yield (TMY) respectively were analyzed. Data used in this study obtained from mountain does at private project in Raselain Village/ Akre Region/ Duhok governorate. The data related to two milking seasons (2016-2017) and (2017-2018). The animals were allowed to graze natural pasture and stubble, straw and ground oak acorns were providing whenever required. Does were flushed 2 weeks prior to mating and kidding season. The flock was placed on a regular health program. Does were milked by hand at biweekly intervals starting from the first week post kidding till the does are dried off. ADMY was calculated by multiplying test day milk yield * 2. While TMY calculated by multiplying ADMY by lactation period. Statistical analysis of data was carried out by using GLM procedure within SAS programme. This model includes effects of doe's age, year and season of kidding, birth's type and sex and weight of doe at kidding on milk traits. Effect of doe added to above model as a random effect to estimate their repeatability using Restricted Maximum Likelihood method. Overall means for ADMY, MYAW and TMY were 0.727, 54.49 and 129.32 kg respectively. Results showed that the age of does had significantly higher effect (P&lt; 0.01) on all studied traits of milk. Does aged 4.5 years produce significantly higher ADMY (0.772 kg), and accordingly TMY (136.88kg), while higher MYAW recorded for does aged 3.5 years beside 4.5 years. The effectiveness of year was significant (P&lt; 0.01) on all milk yield traits. Also season of kidding affect all studied milk traits significantly (P&lt; 0.01), whereas the does kidding in winter had significantly higher ADMY, MYAW and TMY than those kidding in spring season. The effects of type of birth and sex of kids were significant on all milk traits. Does with female twins produced significantly more ADMY comparing with does having male or female singles only. Does with female twins and male and female twins produced significantly much MYAW. Does with female twins yield significantly higher TMY when compared to those in the other groups, on the same time there were no significant differences in TMY of does with male twin and does with male and female twin. There was no significant effect of doe weight at kidding on all studied traits and the regression coefficients were positive for ADMY (0.0003 kg/kg), and TMY (0.085 kg/kg) while the regression was negative for MYAW (- 0.0024 kg/kg). Repeatability estimates of ADMY, MYAW and TMY were 0.24, 0.31 and 0.27 respectively.&#x0D; It sum: due to the effectiveness of the fixed factors on the studied traits, hence adjusting records is necessary. The estimates of repeatability indicate that selection of does as well their kids depending on their milk production will improve the productivity in the next year.

Predicting grass dry matter intake, milk yield and milk fat and protein yield of spring calving grazing dairy cows during the grazing season

Evaluation of fertility in relation to milk production and productivity of Murrah buffaloes

The open days period is one of the components of the physiological cycle of the cow, during which it must be prepared for effective insemination. The duration of this period as a production indicator gives a general idea of the reproductive traits of the herd as a whole, and of each animal in particular. In order to increase milk production, it is possible to extend the open days period to obtain a longer lactation. Studies of this issue show that at the same time the dry period also extends and the average daily milk yield as the whole for lactation decreases. The purpose of the research was to determine the level of milk productivity and reproductive ability of cows depending on the duration of the open days period. The research has been carried out under the conditions in the APC “Emurtlinsky” in the Tyumen region, which is a breeding farm for the breeding of cattle of Holstein breed. It has been found that with an increase in the duration of the open days period from 93 days in the control group to 146 days in the experimental group the duration of barrenness was 3 and 56 days, respectively. It has been found that on the 1st day of milk yield per cow, the milk loss was 4,9 kg, and the absolute annual milk loss in the cows of the experimental group was in the range of 275 kg. The conducted studies suggest that with the increase in the duration of calving interval, there is the decrease in the milk yield of cows per year. The use of cows with the increase in the open days period above the norm recommended by specialists is unjustified. The increase in milk yield due to the lengthening of the lactation period is not effective, because it eventually leads to the increase in the number of days of barrenness and milk loss.

The number of secretory cells in the mammary gland is often cited as a major determinant of milk production. However, literature data for proxy measures of secretory cell number do not fully support such a claim. In particular, measurements of total mammary DNA in livestock explain only <25% of variation in milk yield, probably because of tissue heterogeneity for DNA concentration. Relative to BW, measurements of udder size in dairy cattle, as total DNA or udder weight, are approximately double those seen in most other livestock classes. Therefore, selection for dairy production, not surprisingly, has resulted in cows with greater secretory capacity. There is limited evidence that genetic selection is still increasing udder size in some cattle populations, but more recent data are needed. It is contended that the most important period of mammary growth for determination of milk yield is that occurring in pregnancy and early lactation. Mammary development is largely complete, at term, in sheep, goats, and cattle, but in pigs, the udder continues to grow during the first 3 wk of lactation, depending, in part, on litter size. Increased litter size in sheep and goats will enhance the extent of mammary development at the end of gestation (and milk yield) by 20 to 25%. However, twinning in dairy cattle does not affect milk production and, by inference only, is not likely to affect numbers of secretory cells at term. Milking frequency and suckling intensity in very early lactation will increase milk yield in cows and increase mammogenesis and milk yield in sheep, indicating that even at term, the ruminant gland retains some capacity for further development, if demand requires it. There is limited understanding of the hormonal signals in pregnancy that regulate mammary development relative to the number of young carried. Furthermore, the genetic differences between dairy and beef cattle that lead to substantially greater udder size in the dairy breeds have not been identified. During lactation, the drivers for secretory cell loss in relation to milking frequency and nutritional status are still not known. Measurement of mammary development and using this phenotype in genomewide association studies to identify key genetic variants for mammogenesis will provide knowledge that is fundamental to understanding the quantitative regulation of milk production.

Glucose Metabolism in Lactating Cows in Response to Isoenergetic Infusions of Propionic Acid or Duodenal Glucose

The present experiment was conducted at Bull Mother Experimental Farm (BMEF), College of Veterinary Science and Animal Husbandry, Anjora to study the relationship between skin thickness and milk yield of Sahiwal cows. The overall mean skin thickness of neck, dewlap, chest, abdomen, flank, hind quarter, udder and rump was 3.44±0.06, 3.49±0.06, 3.53±0.06, 4.53±0.08, 5.62±0.12, 4.07±0.07, 2.45±0.04 and 6.63±0.17 mm respectively. Analysis of variance showed that that the effect of skin thickness was statistically significant (P&lt;0.01) on total milk yield and daily milk yield. The findings of milk yield in relation to different categories of skin thickness, it was observed that cows total milk yield per lactation was highest for cows with low skin thickness of dewlap (1673.41±95.67 litre) and abdomen (1680.57±99.94 litre). The correlation coefficient between skin thickness of all the sites with daily milk yield was negatively correlated except for abdomen and udder region. Regression coefficient indicated that a decrease in skin thickness by 1 mm would cause an increase in average daily milk yield by 3 to 28 kg.

Milk production and milk composition were measured in 1056 crossbred ewes managed under pasture grazing in a lamb production system. Most ewes were milked on three occasions at ~3, 4 and 12 weeks of lactation. The ewes were the progeny of mainly Merino dams and 91 sires from several maternal crossing breeds including Border Leicester, East Friesian, Finnsheep and Coopworth. The ewes were born over 3 years and run at three sites where they were joined naturally to meat rams. Most of the ewes were first parity (autumn-joined at 7 months of age and spring-joined at 14–17 months of age), with the remainder second or third parity. The cohorts of ewes and sites were linked genetically by three common maternal sires. The 4-h oxytocin-induced milking procedure was used to estimate daily milk production and milk samples were analysed for composition (fat%, protein% and lactose%). Daily milk yield and milk composition traits were analysed using restricted maximum likelihood mixed models procedures. The sire breed of crossbred ewes was significant for milk yield (P &lt; 0.01), fat% (P &lt; 0.01) and lactose% (P &lt; 0.05). There was a significant (P &lt; 0.01) interaction of sire breed × days of lactation, mainly due to the relatively higher milk yield of the East Friesian and White Suffolk cross ewes compared with the other crosses, at the end of the lactation. The East Friesian cross ewes had lower milk fat% than the other cross ewes. Ewes suckling multiple lambs had 29% higher peak milk yield than those bearing and suckling single lambs (P &lt; 0.001). There was an increase in peak milk yield of the ewes from first to second parity, and third parity ewes had a greater decline to the end of lactation causing a significant interaction (P &lt; 0.001). The overall decline in milk yield from peak to late lactation was –21.2 ± 0.7 g/day. Separate analysis showed a significant increase in milk yield with ewe pre-joining weight (regression 6.1 ± 1.8 g/day.kg). The estimate of heritability for daily milk yield was 0.24 ± 0.04 at 90 days of lactation and 0.10 ± 0.02 at 21 days of lactation. The estimates of heritability for the milk composition traits were generally moderate. Estimates of genetic correlations between measurements early and late in the lactation for milk yield and most composition traits were high. The within ewe by stage variance component estimates of repeatability were moderate to high for milk yield, fat% and protein%, with lactose% being low.

To determine the effects of diets supplemented with protected fat (PF) on milk production and reproductive performance, fifteen lactating Holstein cows weighing 490-540 Kg and having 1-4 parities were divided in a completely randomized block design into three similar groups. Cows in the 1st group were individually fed the control diet, while those in the 2nd and 3rd groups were fed control diet supplemented with 3% and 5% of Ca salt of fatty acids (Magnapac) on dry matter basis of concentrate feed mixture (CFM), respectively. The experimental feeding period lasted from 2-3 weeks pre-partum up to the 120 day-post-partum or conception. At calving, duration of placental drop (PD) and uterine involution (UI) were determined. Live body weight (LBW), body condition score (BCS), feed intake (FI) and average daily milk yield (ADMY) were biweekly recorded at the 15 , 30, 45 and 60 lactation days. During the post-partum period, interval from calving to conception (DO), and then number of services per conception (NSC) were recorded. Results showed insignificant differences in LBW, however, cows in 5% PF group showed slight increase in LBW (1.4%) versus reduction in LBW of 3% PF (-2.9%) and control (-5.1%) groups. There were insignificant group differences in BCS, although BCS of 5% PF group was the best as compared to 3% PF or control groups.FI fro CFM of 5% PF group was lower than those of 3% and control groups (10.59 vs. 10.99 and 11.15 kg), but the difference was not significant. ADMY was higher (P<0.05) in 5% than in 3% and control groups (25.19 vs. 24.33 and 24.25 kg/60 d lactation). The duration of PD markedly reduced (P<0.05) by about 3.6 and 3.1 days and UI reduced (P≥0.05) by 3.2 and 3.0 days in 3 and 5% PF groups as compared to the control group, respectively. Also, NSC reduced (P<0.05) to 1.6 and 1.2 services in 3 and 5% PF groups as compared to 3 services in control group. Number of DO was shorter (P<0.05) in 3 and 5% PF groups (40.2 and 46.2 d) than in control one (88.6 d). Feeding PF diets at a level of 5% increased milk yield, feed efficiency and reproductive performance, but showed economic feed efficiency lower than feeding lactating Holstein cows on the control diet.