The effects of underfeeding for 6 months during pregnancy and lactation on blood constituents, milk yield and body weight of dairy cows

Effects of diseases on test day milk yield and body weight of dairy cows from Danish research herds.

Short communication: Novel method to predict body weight of primiparous dairy cows throughout the lactation

Impact of Social Disorganization on Behavior, Milk Yield, and Body Weight of Dairy Cows

Brown midrib corn silage (BMRS) is used as an alternative to conventional corn silage (CS) to increase milk yield because of its higher neutral detergent fibre digestibility (NDFD) and DM intake (DMI). Forty Holstein dairy cows were used in a completely randomised design with a 2 × 2 factorial arrangement. Two groups of 13 cows in early lactation (EL) and 7 in late lactation (LL) were fed with a total mixed ration including brown midrib (BMR) or conventional corn silage (C), for a period of 42 days. The cows were milked twice a day, milk yield and DMI were recorded, and NDFD was estimated. Milk composition was measured twice a week and milk fatty acid profile was quantified on the final week of the experiment. In EL, BMR diet increased DMI, NDFD, milk and protein yield whereas milk fat content and yield were decreased. Concentrations of trans-10 C18:1 and trans-10, cis-12 C18:2 in milk were higher in BMR. In LL cows DMI was similar between BMR and C whereas milk and fat yields tended to be higher in C. Fat-corrected milk yield was greater in the C diet. The effect of the BMRS on DMI and milk yield depended on stage of lactation, justifying its use in early lactation. The lower milk fat concentration, observed when BMRS was included in the diets, could be explained in part by an increased concentration of trans-10 C18:1 and trans-10, cis-12 C18:2.

Combining selection for carcass quality, body weight, and milk traits in dairy cattle.

Eight Friesian cows in early lactation and eight in late lactation were used in crossover experiments to measure the effects of allowing drinking water for 24 hours a day or for 20 minutes before each milking. Experiments were done during summer in the tropical upland environment of the Atherton Tablelands, Queensland. Free water intakes averaged 78 and 60 kg cow-1 day-1, and milk yields 13.8 and 8.9 kg cow-1 day-1 for cows in early and late lactation respectively. Cows with restricted access to water drank 84 per cent of the water intake of cows with unrestricted access to water. Maximum water intake at one drink averaged 67 kg cow-1 for cows with restricted access to water. Water intake was positively related to maximum air temperature and hours of sunshine a day (P < 0.05), and negatively related to rainfall and relative humidity (P < 0.05). Milk yield, composition and freezing point were unaffected by system of water supply. Grazing time from morning to afternoon milking was similar for cows on both treatments, though the pattern of grazing was changed. There was some evidence that milk yield of cows was depressed during the two days immediately after removal of paddock water. In two investigations there was no loss in milk production when drinking water was removed from the paddock for the one inter-milking interval, morning to afternoon milking.

Concentrations of blood constituents in genetically high and low milk-production lines of British Friesian and Jersey cattle around calving and in early lactation

Energy and protein deficits throughout hospitalization in patients admitted with a traumatic brain injury

Effects of Feeding Intensity During the Dry Period. 1. Feed Intake, Body Weight, and Milk Production

The objective of this study was to describe daily body weight (BW) changes in the first 100 days of lactation in confined dairy cows and to associate BW loss with productive and reproductive performance. Data included 26,344 daily BW measurements of 372 Holsteins calving between June 2011 and June 2012 in a commercial herd in the South of Brazil. Cows were automatically weighed and were assigned according to parity. Individual measurements were smoothed using cubic splines, generating nadir BW, days to nadir BW and the BW loss (absolute and relative values). This approach used days in milk (DIM) as a single smoothing variable. Body weight at calving differed across parities: 570.5, 653.5, and 699.9 kg, for the 1st, 2nd and 3rd and subsequent parities, respectively. Body weight at nadir also differed across parities: 521.5, 608.8, and 647.3 kg, respectively. Mean days from calving BW to nadir BW and mean loss of BW (kg) from calving to nadir BW did not differ across parities, but relative BW change (kg/100 kg) was larger in animals in first parity (-8.4 kg/100 kg) than second parity (-6.6 kg/100 kg). However, cows in first parity had more chances for good reproduction than cows in third and subsequent parities (44.0% vs. 30.7%, respectively). There was no difference in the probability of adequate reproduction (pregnant until 180 DIM) among cows with low, medium, or high milk yield. Furthermore, cows with low and medium BW loss (below 60 kg of BW change) showed more likelihood to adequate reproduction than cows with high BW loss (above 60 kg of BW): 45.5 and 45.8% vs. 24.4%, respectively. Improvements in fertility of dairy cows should be achieved by minimizing body weight loss in early lactation.

The present study investigated the influence of rumen bypass fat-supplemented total mixed ration (TMR) on milk production of tropical crossbred, dairy cows. Twelve stall-fed, tropical crossbred, dairy cows were studied from calving to 15 weeks of lactation. The cows were 397.6 kg in body weight and produced 9.14 L/cow/day milk at the first week of lactation. The experiment was on a complete randomized design with two treatments (i.e., basal diet alone and basal diet with bypass fat supplement) each consisting six (n = 6) replicate cows. During the experimental period, while cows of both treatments were individually fed with respective basal diet (TMR), only the cows allocated for experimental dietary treatment were supplemented with rumen bypass fat (200 g/cow/day) containing calcium salts of long-chain fatty acids. Feed intake, body weight (BW), and milk yield of cows were recorded. Proximate composition of feed, milk composition, and blood metabolic profile of cows were assessed. Dry matter intake and BW of cows were not affected (P > 0.05) by supplementation of rumen bypass fat. The cows supplemented with bypass fat had recorded significantly higher (P < 0.05) milk production compared with cows that did not receive bypass fat supplements until eleventh week of the lactation. As such, bypass fat supplementation resulted 132.38 L/cow higher (P < 0.05) cumulative milk production at 15 weeks compared with their counterparts (1142 vs. 1010 L/cow). But, milk fat, solid non-fat (SNF), protein, and milk urea nitrogen (MUN) contents were not influenced (P < 0.05) by bypass fat supplementation. Bypass fat-supplemented cows had comparatively greater (P < 0.05) serum non-esterified fatty acids (NEFA) level around 6-8 weeks of lactation. However, the serum metabolites' (i.e., NEFA, betahydroxy butyric acid (BHBA), albumin, calcium, and phosphorous) contents of both treatments varied within their respective reference range throughout the experiment. Neither the fat-supplemented cows nor their counterparts experienced negative energy balance (NEB). Benefit cost ratio of bypass fat supplementation confirmed that there is a direct financial benefit of bypass fat supplementation until 12.7th week of lactation. In conclusion, bypass fat supplementation with TMR feeding during early lactation is recommended to increase the milk production of tropical crossbred dairy cows with medium production.

Relationships of concentrations of certain blood constituents with milk yield and age of cows in dairy herds

An experiment was conducted with Holstein-Friesian cows to determine the effect on milk yield and composition of feeding different amounts of meat-and-bone meal (MBM). Thirty-two cows grazed either tropical grass pastures fertilised with nitrogen (GN) or tropical grass-legume pasture (GL). Cows were offered 2.5 kg DM/day of a molasses supplement incorporating 1 of 4 levels of MBM: 0, 250, 500 or 750 g DM/day. The experiment was conducted over the first 160 days of lactation. With GN pastures, fat-corrected milk (FCM) yield (kg/cow.day) for days 1-160 of lactation was linearly related to the intake of MBM (kg DM/cow.day) and was described by the equation FCM = 14.0 + 1.84 MBM (P&lt;0.01, R2 = 0.95). Most of this response occurred in the first 100 days of lactation, when significant I (P&lt;0.05) relationships between milk yield, FCM yield and intake of MBM were found. Milk yield and FCM yield of cows grazing grass-legume pastures were increased by feeding MBM, but the FCM response was a mean of 32% less than with the nitrogen-fertilised pasture and non-significant at the 5% confidence level. The following mean values over 160 days were recorded for cows on GN and GL pastures, respectively: milk yield, 15.8 and 17.4 kg/day; FCM yield, 14.6 and 16.7 kg/day; butterfat, 3.54 and 3.69%; solids-not-fat, 8.40 and 8.59%; lactose, 4.91 and 4.95%. It was concluded that a MBM supplement will increase the milk yield for cows grazing nitrogen-fertilised pastures, but only during early lactation.

Effects of Sodium Carbonate on Milk Yield, Milk Composition, and Blood Components of Dairy Cows in Early Lactation

Effect of dietary starch level and high rumen-undegradable protein on endocrine-metabolic status, milk yield, and milk composition in dairy cows during early and late lactation