Crossbred Holstein Friesian Research Articles

Voluntary automatic milking in combination with grazing of dairy cows: Milking frequency and effects on behaviour

Automatic milking systems (AMS) enable cows to be milked without human interference. Such systems are more acceptable to consumers and from the animal welfare point of view if they can be combined with grazing in the summer season. In this study, grazing was combined with fully automatic milking for a group of 24 crossbred Holstein–Friesian cows. It was assumed that the cows would visit the AMS voluntarily. Zero grazing (G0) was compared with restricted grazing (cows could spend up to 12 h outdoors daily; G12) and unrestricted grazing (cows could spend up to 24 h daily at pasture; G24). The AMS was continuously available in the cowshed adjacent to the pasture of 1.5 ha. Water was available in the barn, but not at pasture. The average daily milking frequency was 2.3 in G24 compared with 2.5–2.8 in the other treatments ( p<0.01). The reason was that the cows spread their visits to the AMS less evenly over the day in G24 (more visits in the afternoon and less visits at night; p<0.01). In the grazing treatments, the cows spent more time eating forage ( p<0.01). The lying times did not differ between the treatments, but the cows lay between 80 and 99.6% of their total lying time at pasture when they had the opportunity to be outdoors. In the grazing treatments, cows entered or left the barn in the company of at least one other cow in 76.6 to 90.7% of the cases. The cows' arrival times at the barn or pasture were not randomly distributed ( p<0.01). In G24, cows spent less time in the pasture between 1000 and 1700 h when the Black Globe Humidity Index was high ( p<0.01), and, related to that, a likeliness for conditions of heat stress. It was concluded that automatic milking on a voluntary basis can indeed be combined with grazing. Grazing seems to be advantageous for the welfare of the cows, as they clearly preferred to lie in the pasture rather than in the cubicles. For the farmer, restricted grazing is more reliable than unrestricted grazing, as milking frequency will be higher on average. Farmers wishing to apply automatic milking with grazing should manage this flexibly, in accordance with ambient conditions, as the weather affects cow behaviour.

Behaviour of dairy cows under free or forced cow traffic in a simulated automatic milking system environment

The introduction of fully automatic milking systems (AMS) on dairy farms can only succeed if cows visit the system more or less voluntarily, at regular intervals. This can be arranged by either forced or free cow traffic. In the case of forced cow traffic, the AMS is the only route from the lying area to the feeding area. An alternative is free cow traffic, where the cows can decide whether to visit the AMS or not. The behaviour in 3 × 20 crossbred Holstein Friesian dairy cows in three experiments (experiment Ia, Ib and II) was studied in a cubicle house with a selection system consisting of a selection stall and a concentrate feeder, simulating an AMS. Cows could obtain 250 g of concentrate in the system once every six hours. Actual milking occurred in a conventional milking parlour twice a day. Experiment Ia consisted of (1) a reference phase with no use of the selection system, (2) free cow traffic, (3) forced cow traffic, and (4) a reference phase. Experiment Ib was a repetition of experiment Ia. Experiment II was divided into (1) a reference phase with no use of the selection system, (2) forced cow traffic with two one-way passages between the feeding and lying areas, (3) forced cow traffic with one one-way passage, (4) free cow traffic with one free passage between the feeding and lying areas, and (5) free cow traffic with two such passages and (6) a reference phase. The number of visits paid to the selection system by individual cows appeared to be consistent in the different phases in each experiment ( r = 0.52 in experiment I ( P < 0.05); r = 0.68−0.86 ( P < 0.01) in experiment II). In experiments Ia and Ib, cows seemed to visit the selection system more often during forced cow traffic than during free cow traffic, but this was because some of the cows did not visit the system at all during free cow traffic. Therefore, the differences were not significant. In experiment II, cows paid the same number of visits to the selection system during different types of cow traffic, but when two passages were open during free cow traffic, the cows visited the system less ( P < 0.01). During forced cow traffic, cows spent more time standing on the slatted floor in the feeding area, spent less time standing at the feeding gate and made less journeys from the lying to the feeding area (significant in two of three experiments; P < 0.01). It was concluded that forced cow traffic may improve the frequency of visits to the AMS, but somewhat restricts the cows' behaviour, and may, therefore, be questionable. Free cow traffic could work if cows are previously conditioned to take the route to the AMS.

Effect of protein nutrition on ammonia emission from a cubicle house for dairy cattle

The effect of protein nutrition on the urinary concentration of urea and subsequent emission of ammonia into the atmosphere was studied using a mechanically ventilated cubicle house containing 34 lactating dairy cows (cross bred Holstein Friesian and Dutch Friesian). Two silage-based diets with different amounts of rumen-degradable protein balance (OEB), were alternately fed during six 3-week periods. Diet L contained a small amount of OEB and resulted in a 39% lower emission rate, compared with diet H which contained a high amount of OEB. The concentration of urea in the urine samples was 42% lower when feeding diet L compared with diet H. A decrease in urea concentration as a result of a lower OEB could contribute substantially towards diminishing the emission of ammonia from cubicle houses for dairy cattle. L'effet de la nutrition protéique sur la concentration d'urée dans l'urine et l'émission correspondant d'ammoniaque dans l'atmosphère ont été étudiés en utilisant une étable à logettes avec ventilation mécanique, contenant 34 vaches laitières (croisées Holstein). Deux régimes à base d'ensilage avec différents niveaux de protéine dégradable dans le rumen (OEB) ont été distribués en alternance pendant six périodes de trois semaines. Le régime L contenait peu d'OEB et a permis de diminuer de 39% le rythme d'émission, par rapport au régime H qui contenait beaucoup d'OEB. La concentration d'urée dans les échantillons d'urine a été de 42% inférieure en régime L par rapport au régime H. Une diminution de la concentration en urée suite à une diminution de l'OEB pourrait contribuer de façon importante à la diminution de l'émission d'ammoniaque par les étables à logettes des vaches laitières. In einem mechanisch belüfteten Boxenstall, in dem 34 laktierende Milchkühe (Kreuzungen aus Holstein Friesian und Holländischen Schwarzbunten) gehalten wurden, ist der Einfluβ der Proteinernährung auf die Harnstoffkonzentration im Urin und die daraus folgende Ammoniakemission in die Atmosphäre untersucht worden. Zwei auf Silage basierende Rationen mit unterschiedlichem Gehalt an im Pansen abbaubarem Protein (OEB) wurden alternativ während sechs 3-Wochen- Perioden gefüttert. Die Ration L zeichnete sich durch einen geringen Gehalt an OEB aus und hatte eine um 39% geringere Emissionsrate im Vergleich zu der Ration H mit einem hohen Gehalt. Die Konzentration von Harnstoff im Urin war bei der Ration L um 42% geringer im Vergleich zur Ration H. Eine Reduzierung der Harnstoffkonzentration im Ergebnis einer geringeren Menge an im Pansen abbaubarem Protein könnte substantiell zur Verringerung der Emission von Ammoniak in Boxenställen für Milchkühe beitragen.

Carcass composition of veal calves dependent on genotype and feeding level

ABSTRACTDutch Friesian purebred and Holstein Friesian-Dutch Friesian crossbred veal calves were used to study effects of genotype and feeding level on carcass composition. Carcass analyses were carried out on a total of 56 calves of two genotypes. Calves were reared for 22 weeks and given food dependent on age. From 1 to 16 weeks calves were given the same amount of milk replacer. At week 16, calves were assigned to either a high or low feeding level. Total energy intakes for the two groups were 5062 MJ metabolizable energy (ME) and 5408 MJ ME, respectively. Carcass weight and carcass composition traits showed no significant interaction between genotype and feeding level. Dutch Friesians had higher lean: bone ratios than Holstein Friesian crossbreds (3·85 v. 3·67). Differences between the two genotypes for fat and lean proportions in the carcass were not significant. Average proportions for lean and fat were 653 and 134 g/kg.Differences between the two feeding levels for carcass composition were significant. Calves on the low feeding level had 655 g lean and 131 g fat per kg, while calves on the high level had 645 g lean and 143 g fat per kg.The influence of the dissection technique on the differences in lean and muscle proportion between groups was studied on 18 carcasses using a standardized butcher's method (the Institute of Animal Husbandry (IVO) standard method) and the European Economic Community (EEC) reference method for beef. Average proportion of lean was 640 g/kg by the IVO method and of muscle was 557 g/kg by the EEC method. The difference between the two genotypes for lean proportion was smaller by the' EEC method due to the more complete separation between muscle and fatty tissue. Dutch Friesians had more intermuscular fat than Holstein Friesian crossbreds. Results of the EEC reference method indicate differences between the two feeding levels for fat as well as for protein deposition.

The effect of genotype and metabolizable energy intake on protein and fat gain in veal calves

ABSTRACTAn experiment was carried out with 20 male veal calves to study differences in energy metabolism between pure Dutch Friesian and Holstein Friesian crossbred calves, containing a high proportion of Holstein Friesian genes (0·79). Two metabolizable energy (ME) intakes were given. The effects of genotype and ME intake on live-weight gain and its fat and protein composition were measured by indirect calorimetry and by the total collection of faeces and urine. Energy and nitrogen balances were measured for each calf during the last 5 weeks of the fattening period of 22 weeks.The difference in live-weight gain between the Holstein Friesian crossbreds and the Dutch Friesian calves was not significant but small differences in protein and fat composition of live-weight gain were found. Fat gain was closely related to ME intake (r = 0·95), but the correlation coefficient between ME intake and protein gain was only 0-36. Live-weight gain had a high correlation with protein gain (r = 0·70) but a lower correlation with fat gain (r = 0·29).Veal calves at the end of the fattening period had a declining protein gain as age increased. Calves given a high ME intake (&gt; 2 × maintenance) may require diets containing less than 216 g crude protein per kg diet at the end of the fattening period.The study indicates that Holstein Friesian crossbred veal calves and Dutch Friesian veal calves have similar ME requirements.

A function for live-weight change between two calvings in dairy cattle

ABSTRACTA function to describe live-weight changes of dairy cows between two calvings is constructed. The following measurements were used: live-weight level (scale), pregnancy parameter, maximum decrease of live weight during the lactation and the time during lactation at which minimum live weight occurred.An analysis was carried out for each of 71 dairy cows of two genotypes, Dutch Friesian and Holstein Friesian crossbreds, given a high or a low concentrate diet. Data set 1 contained data of 40 weeks lactation and data set 2 data from calving to calving.The mean residual standard deviation per genotype-diet group ranged from 11 to 14 kg. The mean R2 ranged over the subgroups in data set 1 from 0·715 to 0·792 and in data set 2 from 0·857 to 0·906. Diet had a significant influence on the magnitude of the decrease in live weight during the lactation (71 v. 46 kg) and the mean time during the lactation at which minimum live weight occurred. The latter time ranged from day 58 to 100 over the four groups and a diet effect existed. The pregnancy parameter could not be estimated accurately based on measurements during the first 40 weeks of lactation. The correlation coefficient between the pregnancy parameter in data sets 1 and 2 ranged from +0·13 to +0·78. The other parameters showed coefficients from +0·82 to +0·99.