Autumn-calving Holstein-Friesian Cows Research Articles

An examination of two concentrate allocation strategies which are based on the early lactation milk yield of autumn calving Holstein Friesian cows

The objective of this experiment was to compare the effects of two concentrate feeding strategies offered with a grass silage and maize silage diet on the dry matter (DM) intake, milk production (MP) and estimated energy balance of autumn calved dairy cows. Over a 2-year period, 180 autumn calving Holstein Friesian cows were examined. Within year, cows were blocked into three MP sub-groups (n=9) (high (HMP), medium (MMP) and low (LMP)) based on the average MP data from weeks 3 and 4 of lactation. Within a block cows were randomly assigned to one of two treatments (n=54), flat rate (FR) concentrate feeding or feed to yield (FY) based on MP sub-group. Cows on the FR treatment were offered a fixed rate of concentrate (5.5 kg DM/cow per day) irrespective of MP sub-group. In the FY treatment HMP, MMP and LMP cows were allocated 7.3, 5.5 and 3.7 kg DM of concentrate, respectively. The mean concentrate offered to the FR and FY treatments was the same. On the FR treatment there was no significant difference in total dry matter intake (TDMI, 17.3 kg) between MP sub-groups. In the FY treatment, however, the TDMI of HMP-FY was 2.2 kg greater than MMP-FY, and 4.5 kg greater than LMP-FY (15.2 kg DM). The milk yield of LMP-FR was 3.5 kg less than the mean of the HMP-FR and MMP-FR treatments (24.5 kg). The milk yield of the HMP-FY treatment was 3.6 and 7.9 kg greater than the MMP-FY and LMP-FY treatments, respectively. The difference in MP between the HMP sub-groups was 2.6 kg, which translates to a response of 1.4 kg of milk per additional 1 kg of concentrate offered. There was no significant difference in MP between the two LMP sub-groups; however, MP increased 0.8 kg per additional 1 kg of concentrate offered between cows on the LMP-FR and LMP-FY treatments. The estimated energy balance was positive for cows on the LMP-FR treatment, but negative for cows on the other treatments. The experiment highlights the variation within a herd in MP response to concentrate, as cows with a lower MP potential are less responsive to additional energy input than cows with a greater MP potential. Cows with a greater MP capacity did not substitute additional concentrate for the basal forage, which indicates an additional demand for energy based on ability of individual cows to produce milk.

The effect of concentrate feeding amount and feeding strategy on milk production, dry matter intake, and energy partitioning of autumn-calving Holstein-Friesian cows

The objective of this study was to compare the milk production, dry matter intake, and energy partitioning of autumn-calving Holstein-Friesian cows offered a high or low amount of concentrate using 1 of 2 feeding strategies. One hundred and eight autumn-calving Holstein-Friesian cows were blocked based on milk production data from wk 3 and 4 of lactation, and were divided into low-, medium-, and high-milk yield subgroups. Cows were randomly assigned to 1 of 4 treatments (n=27) in a 2×2 factorial design. Treatment factors were concentrate feeding amount, high concentrate=7.0 (Hi) or low concentrate=4.0kg of DM/cow per day (Lo), and concentrate feeding strategy, flat rate (FR) or group-fed to yield (GFY). In the GFY treatments, cows were allocated concentrate based on their milk yield in the third and fourth weeks of lactation. The lowest-yielding cows (n=9) received 5.3 and 2.3kg of DM of concentrate on the Hi and Lo treatments respectively, the highest-yielding cows (n=9) received 8.7 and 5.7kg of DM of concentrate on the Hi and Lo treatments respectively, and the average yield cows received the same amount of concentrate as the corresponding FR group (i.e., 7.0 and 4.0kg of DM of concentrate on the Hi and Lo treatments, respectively). The proportion of forage in the diet was 63% of total dry matter intake (TDMI) for the Hi treatment and 75% of TDMI for the Lo treatment. No significant interaction was noted between concentrate feeding amount and concentrate feeding strategy for dry matter intake or milk yield. Cows on the Hi treatment had a higher TDMI (18.7±0.36kg/cow per day) compared with cows on the Lo treatment (15.8±0.36kg/cow per day). The milk yield of cows offered the Hi treatment was 1.3kg/cow per day higher than the milk yield of cows on the Lo treatment (23.8±0.31kg/cow per day). Milk solids yield was 0.10kg/cow per day higher on the Hi treatment than on the Lo treatment (1.83±0.03kg of DM/cow per day). Cows on the Hi treatment had an estimated net energy demand of 18.0±0.38 UFL (unité fourragère lait)/cow per day and a net energy intake of 17.6±0.33 UFL/cow per day during the experimental period. Cows on the Lo treatment had an energy demand of 16.8±0.38 UFL/cow per day and an energy intake of 14.9±0.33 UFL/cow per day. No significant difference in TDMI, milk yield, milk solids yield, or energy balance was observed between the FR and GFY treatments. By increasing the total amount of concentrate offered, cows had higher TDMI and energy intake, which resulted in increased milk production and reduced negative energy balance and body condition score loss.

Increasing home-grown forage consumption and profit in non-irrigated dairy systems. 1. Rationale, systems design and management

The profitability of dairy businesses in southern Australia is closely related to the amount of feed consumed from perennial ryegrass-dominant pasture. Historically, the dairy industry has relied on improvements in pasture productivity and utilisation to support profitable increases in stocking rate and milk production per hectare. However, doubts surround the extent to which the industry can continue to rely on perennial ryegrass technology to provide the necessary productivity improvements required into the future. This paper describes the design and management of a dairy systems experiment at Terang in south-west Victoria (780-mm average annual rainfall) conducted over four lactations (June 2005–March 2009) to compare the production and profitability of two forage base options for non-irrigated dairy farms. These options were represented by two self-contained farmlets each milking 36 mixed-age, autumn-calving Holstein-Friesian cows at peak: (1) well managed perennial ryegrass pasture (‘Ryegrass Max’, or ‘RM’); and (2) perennial ryegrass plus complementary forages (‘CF’) including 15% of farmlet area under double cropping with annual species (winter cereal grown for silage followed by summer brassica for grazing on the same land) and an average of 25% of farmlet area in perennial pasture based on tall fescue for improved late spring–early summer feed supply. The design of these systems was informed by farming systems models (DairyMod, UDDER and Redsky), which were used to estimate the effects of introducing different forage options on farm profitability. The design of the CF system was selected based on modelled profitability increases assuming that all forage components could be managed to optimise forage production and be effectively integrated to optimise milk production per cow. Using the historical ‘average’ pasture growth curve for the Terang district and a mean milk price of $3.71 per kg milk solids, the models estimated that the return on assets of the RM and CF systems would be 9.4 and 15.0%, respectively. The objectives of the experiment described here were to test whether or not such differences in profitability could be achieved in practice, and to determine the risks associated with including complementary forages on a substantial proportion of the effective farm area. Key results of the experiment are presented in subsequent papers.

Comparative Evaluation of Alternative Forages to Grass Silage in the Diet of Early Lactation Dairy Cows

Fifty-six autumn-calving Holstein-Friesian cows, blocked on the basis of days in milk (27.6±10.65 d), lactation number (3.1±2.21), and preexperimental milk yield (28.4±6.69kg) were used to examine the effects of replacing 330 g/kg of dry matter (DM) of first-cut perennial ryegrass silage with either fermented whole-crop wheat (WCW), urea-treated processed WCW, or corn silage on subsequent feed intake, milk production, and efficiency of nitrogen utilization. The DM (g/kg), crude protein (CP, g/kg of DM) and in vitro DM digestibility (g/kg) of the forages were 204, 179, and 762 for grass silage; 389, 90, and 711 for fermented WCW; 795, 141, and 768 for urea-treated processed WCW; and 346, 93, and 783 for corn silage, respectively. Four forage treatments were evaluated as follows: 1) grass silage as the sole forage (GS); 2) a mixture of grass silage and fermented WCW silage, (F-WCW); 3) a mixture of grass silage and urea-treated processed WCW, (UP-WCW); and 4) a mixture of grass silage and corn silage (CS). In all cases, the alternative forages comprised 67% of the forage mix on a DM basis. Isonitrogenous diets were formulated by offering all cows 8kg of concentrate as fed, formulated to different CP concentrations. Cows were offered these diets from 28 to 104 d in milk. Total DM intake and milk yield were greater on UP-WCW (20.0 and 30.2kg/d) and CS (18.3 and 33.2kg/d) than on GS (13.5 and 26.5kg/d). Although DM intake was greater on F-WCW (17.1kg/d) than on GS, milk yield was not significantly greater (+2.7kg/d). Milk protein concentration was greater on F-WCW (30.5 g/kg), UP-WCW (31.3 g/kg), and CS (30.7 g/kg) than on GS (28.5 g/kg). However, there was no difference between treatments in milk fat or lactose concentrations. Body weight change was greater for cows offered GS (−0.27kg/d) than for those offered UP-WCW (−0.01kg/d) and CS (+0.05kg/d) but not compared with those offered F-WCW (−0.06kg/d). There was no effect of treatment on plasma glucose, nonesterified fatty acids, β-hydroxybutyrate, urea, or total protein at d 64±17.4 and d 92±17.4 postpartum. Efficiency of N utilization was greatest for CS with 0.36 of N intake being recovered in milk compared with 0.28, 0.32, and 0.26 for GS, F-WCW, and UP-WCW, respectively. There was no effect of treatment on milk urea N concentration or the urinary allantoin N to creatinine N ratio. The results of this experiment indicate that corn silage is a more suitable supplementary forage to grass silage than fermented or urea-treated processed WCW, with advantages realized in milk production and more efficient N utilization.

Effect of concentrate type on rumen fermentation and milk production of cows at pasture

The experiment was conducted with 15 Autumn-calving Holstein–Friesian cows, three of which were fitted with rumen cannula, that were allowed to access a perennial timothy and meadow fescue sward between 10 June and 12 August 1996. The control treatment (C) consisted of pasture alone. For the other two treatments, cows were fed 4 kg per day of either a concentrate supplement consisting of barley (B) or a treatment (M) containing (g/kg) barley (200), oats (200), wheat bran (220), wheat (110), wheat syrup (60) and molassed sugar beet pulp (200). The experiment was carried out as a replicated ( n=5) 3×3 Latin square design. The grazing area was divided into 15 paddocks and cows were grazed on a 1 to 2-day rotation. There was no treatment effect on rumen pH but the molar proportion of acetic acid in rumen fluid was higher ( p<0.05) in cows grazing pasture alone (C). Ammonia N concentration was lower for M than B ( p<0.01). Concentrate supplementation increased milk yield ( p<0.001), the extent of which was greater for M than B (2.6 versus 1.3 kg per day; p<0.05). Protein yields increased ( p<0.001) due to treatments B (51 g per day) and M (115 g per day). These results indicate that barley is a less suitable concentrate supplement than a mixture, formulated from a range of ingredients since energy corrected milk yield (ECM 20.5 versus 19.2 kg per day), protein (729 versus 665 g per day) and lactose (1000 versus 933 g per day) yields were greater ( p<0.01) in treatment M than B.

Effect of concentrate supplementation on lactation performance of pregnant and non-pregnant Holstein-Friesian dairy cows

The effect of pregnancy on the rate of decline in milk yield from month 5 of gestation onwards has been documented for some time, (Brody et al., 1923), and has been a key factor in choice of calving interval. There has been renewed interest in the possibility of extending the traditional 365 day calving interval, because of higher genetic merit cows and difficulties over live calf exports. The objective of the current work was to look for an interaction between pregnancy status and concentrate supplementation.Sixty-five autumn-calving Holstein-Friesian cows (26 non-pregnant (B) and 39 pregnant (P)) were selected for the experiment; prior to the experiment they were managed on a flat-rate concentrate allocation with forage available ad libitum. The pregnancy-status groups were randomly allocated to receive ad libitum grazed grass and either 0 or 3 kg of 18% crude protein dairy concentrate. The animals were grazed and milked together as one group. The non-pregnant cows were deliberately not inseminated for management reasons (e.g. failure to use Calan gates). During the 10 weeks before imposition of the concentrate treatment, there was no significant difference in milk yield between treatment groups (21.9 (s.e.=1.71) kg/day). The main recording period ran from 10 June until 16 September 1996. Milk yield was recorded daily, milk composition, live-weight and condition scores fortnightly. Data were summarised as means (for milk yield and composition) or slopes (rates of change; for live-weight and condition score (CS; 0-5 scale)) over the period from 3 to 13 weeks after the imposition of the concentrate treatment.

Changes in body components of autumn-calving Holstein-Friesian cows over the first 29 weeks of lactation

AbstractChanges in body composition of 54, second to fourth parity, autumn-calving Holstein-Friesian dairy cows offered grass silage ad libitum and 3(L), 6(M) or 9(H) kg concentrate dry matter per day were measured by serial slaughter at 0, 2, 5, 8, 11, 14, 19, 24 and 29 weeks post partum.Concentrate level had a significant effect on the fresh weights of many of the body fractions with the differences generally being greater between L and M than between M and H. Increasing concentrate level generally reduced the extent of weight loss of body fractions in early lactation and enhanced subsequent repletion. Empty body weight decreased to week 8 and then increased steadily over the remaining 21 weeks, but within this pattern different organs were concomitantly increasing and decreasing. Carcass weight and the weights of the internal fat depots showed a decline over the first 8 weeks and a subsequent increase, udder weight declined throughout, weights of various sections of the digestive tract showed an initial increase then remained steady, whilst liver weight increased throughout.In week 0 the carcass accounted for proportionately 0-61 of the total energy in the body (6278 MJ), of which fat and crude protein (CP) comprised proportionately 0·67 and 0·33, respectively. In early lactation mobilization of fat and CP in the carcass was reduced with increasing level of concentrate. In the non-carcass fraction increasing concentrate level led to a higher weight of CP in the metabolically active organs such as the digestive tract and udder but had little effect on the weight of fat. Nevertheless, there was generally a positive effect of concentrate level on energy content. Total weights of fat, CP and water in the body declined to week 8 then increased over the following 21 weeks. Although weight of CP in the liver increased throughout lactation and weight of fat was elevated in weeks 0 and 2, the energy content of the liver remained fairly constant.Estimates of the change in net energy (NE) associated with live-weight loss and with live-weight gain showed a slight though non-significant difference between the two, despite evidence of a higher concentration of fat associated with gain than with loss, and CP concentration being the same in both cases. The mean value was 19·3 MJ/kg live-weight change.

Body composition and performance of autumn-calving Holstein-Friesian dairy cows during lactation: food intake, milk constituent output and live weight

The importance of measuring partition between body and milk in dairy cows and identifying the factors underlying it has long been recognised. However accurate measurements of partition In the body are few because of the difficulty and expense of the techniques.The purpose of the present experiment was to measure the effects in autumn-calving Holstein-Friesian cows given grass silage ad libitum of amount of concentrate and stage of lactation on body composition by direct (Gibb et al 1992a, b) and Indirect (Kings et al 1992) techniques, adipose tissue metabolism (Walsh et al 1992) and milk production. In a related trial, energy balance was measured in other cows by Indirect calorimetry (Cammell et al 1992).This report covers silage Intake, milk production and live-weight change. Communications on the associated studies are given in the Proceedings of this Meeting.

The influence of carbohydrate source and concentration of crude protein in a concentrate given with grass silage ad libitum on the performance of autumn-calving Holstein-Friesian cows

Carbohydrates in dairy concentrate originate from cereals containing high starch and a variety of by-products with high levels of fibre. Selection is based on unit cost and chemical analysis. Comparisons between starchy and fibrous sources were made at a single level of crude protein (CP) by Thomas et al (1986) and Sutton et al (1987). Voluntary intake of forage increased and yields of fat and protein were similar when fibre replaced starch. The objective of this trial was to extend the range of comparisons by establishing the effects of three types of carbohydrate at four levels of crude protein given with grass silage ad libitum to lactating dairy cows.