Irish Journal of Agricultural and Food Research Volume 44, No 2 2005

Cow factors affecting the risk of clinical mastitis

Irish Journal of Agricultural and Food Research 44: 147–156, 2005

D.P. Berry^† and W.J. Meaney

Teagasc, Moorepark Dairy Production Research Centre, Fermoy, Co. Cork

The objective of the present study was to identify cow risk factors associated with development of clinical mastitis (CM) in subsequent stages of lactation. A total of 3,309 lactations from spring-calving Holstein-Friesian cows were included in the analysis; parity number ranged from one to three, inclusive. A generalised estimating equations approach with a logit link function was used to account for the binary nature of the data and the unequal number of repeated records per cow. The dependent variable was the probability of developing CM in the subsequent stage of lactation. Independent variables included in the model were chosen using stepwise selection; herd, year of birth, month of calving, parity, period of lactation and previous CM history significantly affected the probability of CM. Two-way interactions between parity and period of lactation and between parity and incidence of CM in the previous lactation were also included in the model. A greater probability of developing CM is expected in cows that experienced CM in the previous lactation and/or previously within the same lactation. The probability of CM occurring in cows that experienced at least one case of CM in the previous lactation was 0.92 to 3.75 times that of a cow that experienced no CM in the previous lactation. It is possible to predict the probability of an animal developing CM in the subsequent stage of lactation when information is available on the parity and month of calving of the animal and its previous history of CM.

Keywords:Clinical mastitis; history; odds; probability
†Corresponding author: donagh.berry@teagasc.ie

Effect of suckler cow genotype on energy requirements and performance in winter and subsequently at pasture

Irish Journal of Agricultural and Food Research 44: 157–171, 2005

M. McGee^1,2†, M.J. Drennan¹ and P.J. Caffrey²

¹Teagasc, Grange Research Centre, Dunsany, Co. Meath

²School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4

Three experiments using a total of 62 Charolais (C) and 110 Beef × Holstein-Friesian (BF) spring-calving cows were carried out to determine the relative energy requirements of the genotypes. Cows were individually offered a restricted allowance of grass silage daily during the last 85 and 107 days pre partum in Experiments 1 and 2, respectively, and ad libitum grass silage during the last 93 days pre partum in Experiment 3. In all 3 experiments grass silage was offered ad libitum during the first 34 days of lactation. In Experiments 1 and 2, cows and calves were grazed together during the subsequent grazing seasons. When fed to appetite, silage dry matter intake was similar for both cow genotypes but was higher for the BF cows when expressed relative to live weight. For Experiments 1 and 2 combined, initial live weights and live weight changes to post-partum, over the indoor period and at pasture were 720 (s.e. 14.1), 613 (s.e. 8.4), –74 (s.e. 4.0), –63 (s.e. 2.7), –106 (s.e. 6.0), –89 (s.e. 4.0) and 120 (s.e. 7.0), 88 (s.e. 5.3) kg for C and BF cows, respectively. In Experiment 3 the corresponding initial live weights and live weight changes to post partum were 759 (s.e. 12.3), 659 (s.e. 9.1) and –63 (s.e. 4.9) and –52 (s.e. 3.5) kg. There was no effect of genotype on body condition score or adipose cell diameter or their changes. Plasma creatinine concentrations were higher (P < 0.001) in C cows than BF cows. It is concluded that the energy requirements of a 660 kg C cow are approximately equivalent to a 600 kg BF cow during late pregnancy.

Keywords:Energy requirements; genotype; intake; suckler cows
†Corresponding author: mmcgee@grange.teagasc.ie

Effect of suckler cow genotype on cow serum immunoglobulin (Ig) levels, colostrum yield, composition and Ig concentration and subsequent immune status of their progeny

Irish Journal of Agricultural and Food Research 44: 173–183, 2005

M. McGee^1,2†, M.J. Drennan¹ and P.J. Caffrey²

¹Teagasc, Grange Research Centre, Dunsany, Co. Meath

²School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4

Survival of the neonatal calf is largely dependent on humoral immunity. The objective of three experiments reported here was to compare cow serum immunoglobulin (Ig) concentration, colostrum yield, composition and Ig concentration and calf serum Ig concentrations at ~8- and 48-h post partum of spring-calving Charolais (C) and Beef B4 Holstein-Friesian (BF) cows and their progeny. Cows were individually offered a restricted allowance of grass silage pre partum in Experiments 1 and 2 and silage ad libitum in Experiment 3. In Experiment 1 calves were assisted to suckle after parturition. In Experiments 2 and 3, colostrum yield and Ig concentration were measured following administration of oxytocin and hand milking of half or the complete udder, respectively. It was intended to feed each calf 50 ml (Experiment 2) or 40 ml (Experiment 3) of colostrum per 1 kg birth weight via stomach tube. Following an 8-h period, during which suckling was prevented, a further colostrum sample was obtained. The decrease in cow serum IgG₁ concentration pre partum was greater (P < 0.05) in BF cows than C cows. In comparison to BF cows, C cows had a lower colostrum yield (P < 0.001) and the colostrum had lower concentrations of dry matter (P < 0.01), crude protein (P < 0.05), fat (P < 0.05), IgG₁ (P = 0.06), IgG₂ (P < 0.01), IgM (P < 0.01) and Ig total (P < 0.05). The mass of IgG₁, IgG₂, IgM, IgA and Ig total in the colostrum produced was significantly lower for C cows than BF cows. Calves from C cows had significantly lower serum Ig subclass concentration at 48-h post partum than calves from BF cows. In conclusion, due to a lower Ig mass produced by their dams, calves from C cows had a lower humoral immune status than those from BF cows.

Keywords: Colostrum; genotype; immunoglobulins; suckler cows
†Corresponding author: mmcgee@grange.teagasc.ie

Effect of suckler cow genotype on milk yield and pre-weaning calf performance

Irish Journal of Agricultural and Food Research 44: 185–194, 2005

M. McGee^1,2†, M.J. Drennan¹, and P.J. Caffrey²

¹Teagasc, Grange Research Centre, Dunsany, Co. Meath

²School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4

Milk yield and pre-weaning calf performance of spring-calving Charolais (C) and Beef × Holstein-Friesian (BF) cows was compared over 3 experiments. Cows were individually offered a restricted allowance of grass silage pre partum in Experiments 1 and 2 and ad libitum silage in Experiment 3. In all three experiments cows received silage to appetite for the first 34 (s.d. 16.2) days of lactation. In Experiments 1 and 2, cows and calves were grazed together during the subsequent grazing seasons. The daily milk yield of C cows was significantly lower from parturition until turnout to pasture (1.8 to 2.5 kg/day lower) and subsequently at pasture (4.5 and 3.1 kg/day lower in Experiments 1 and 2, respectively) than that of BF cows. Calves from C cows consumed more (P < 0.01) concentrate creep feed during the indoor period than calves from BF cows. Compared to calves from BF cows, pre-weaning daily live-weight gain was lower for calves from C cows in Experiments 1 (P < 0.05) and 2 (P = 0.06). The pre-weaning growth response per 1 kg increase in milk yield was greater for calves from C cows than those from BF cows. In conclusion, compared to BF cows the milk yield of C cows was lower resulting in increased calf concentrate intake indoors and lower pre-weaning calf daily live-weight gains.

Keywords: Genotype; milk yield; suckler cows; weaning weight
†Corresponding author: mmcgee@grange.teagasc.ie

Post-weaning performance and carcass characteristics of steer progeny from different suckler cow breed types

Irish Journal of Agricultural and Food Research 44: 195–204, 2005

M.J. Drennan^†, M. McGee and M.G. Keane

Teagasc, Grange Research Centre, Dunsany, Co. Meath

In two experiments a total of 44 steer progeny of spring-calving Charolais (C) and Hereford × Friesian (HF) suckler cows and C sires were slaughtered at approximately 2 years of age. Following weaning they were offered silage and 1 kg of concentrate per head daily during a 5 month winter after which they spent 7 months at pasture. In Experiment 1, animals were given a silage/concentrate diet during a finishing period of either 95 or 152 days. In Experiment 2, steers were offered either a daily diet of silage plus 6 kg of concentrates or concentrates to appetite plus 5 kg of silage (fresh weight) during the final 140-day finishing period. Following slaughter, an 8-rib pistola from each animal was dissected. For the two experiments combined C and HF progeny had carcass weights of 372 and 385 (s.e. 6.1) kg, proportions of carcass as pistola of 467 and 454 (s.e. 2.8) g/kg and pistola meat proportions of 676 and 642 (s.e. 5.1) g/kg, respectively. All fat traits were lower for the C than HF progeny but there was no difference in carcass conformation score. Increasing slaughter weight increased carcass weight (P < 0.001), kidney plus channel fat weight (P < 0.001), and pistola fat proportion (P < 0.001) and decreased the proportions of carcass as pistola (P < 0.05), pistola meat (P < 0.01), and bone (P < 0.05). In conclusion, breed type had no effect on carcass growth but the C progeny had higher meat yield than the HF. Increasing slaughter weight increased fatness and reduced meat yield.

Keywords: Carcass composition, carcass growth, dam breed type
†Corresponding author: mdrennan@grange.teagasc.ie

Cow serum and colostrum immunoglobulin (IgG₁1) concentration of five suckler cow breed types and subsequent immune status of their calves

Irish Journal of Agricultural and Food Research 44: 205–213, 2005

B.M. Murphy^1,2, M.J. Drennan^{1, †}, F.P. O’Mara² and B. Earley¹

¹Teagasc, Grange Research Centre, Dunsany, Co. Meath

²UCD, School of Agriculture, Food Science and Veterinary Medicine, UCD, Belfield, Dublin 4

The objective of this study was to determine the effect of cow breed type on (a) cow serum and colostrum immunoglobulin (IgG₁) concentrations and (b) subsequent calf serum IgG₁ concentration and zinc sulphate turbidity (ZST) units. Five cow breed types were examined: LF (Limousin × Friesian), LLF (Limousin × (Limousin × Friesian)), L (Limousin), C (Charolais) and SLF (Simmental × (Limousin × Friesian)). Three blood samples were taken by jugular venipuncture from the cows at approximately 90, 60 and 30 days pre partum, at parturition and at 15 days or more post partum and from the calves at 48 (40 to 56) h post partum. Prior to suckling a 20 ml sample of colostrum was obtained. Milk yield was estimated using the weigh-suckle-weigh technique. The decrease in serum IgG₁ concentration in cows between 90 days pre partum and parturition was greater (P < 0.01) for LF cows than all other breed types, except SLF. There was no difference between LLF, L, C and SLF cows. There was no effect of cow breed type on colostrum IgG₁ concentration. Milk yield was higher (P < 0.001) for LF cows than all other breed types, while that of SLF was higher than the three remaining breed types, which were similar. Calf serum IgG₁ concentration and ZST units were higher (P < 0.01) for the progeny of LF cows than all others except SLF. There was no difference between the progeny of LLF, L, C and SLF cows. Calf serum IgG₁ was affected by cow breed type and showed a positive relationship with cow serum IgG₁ decreases in late pregnancy.

Keywords: Breed, colostrum, immunoglobulins, suckler cow
†Corresponding author: mdrennan@grange.teagasc.ie

Production and carcass traits of high dairy genetic merit Holstein, standard dairy genetic merit Friesian and Charolais × Holstein-Friesian male cattle

Irish Journal of Agricultural and Food Research 44: 215–231, 2005

M. McGee¹, M.G. Keane^1†, R. Neilan^1,2, A.P. Moloney¹ and P.J. Caffrey²

¹ Teagasc, Grange Research Centre, Dunsany, Co. Meath, Ireland

² School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland

The increased proportion of Holstein genetic material in the dairy herd has consequences for beef production in Ireland. A total of 72 spring-born male calves (24 Holsteins (HO), 24 Friesian (FR) and 24 Charolais × Holstein-Friesians (CH)) were reared from calfhood to slaughter. Calves were artificially reared indoors and spent their first summer at pasture following which they were assigned, on a breed basis, to a factorial combination of two production systems (intensive 19-month bull beef and extensive 25-month steer beef) and two slaughter weights (560 and 650 kg). After slaughter the pistola hind quarter was separated into fat, bone and muscle. Live-weight gain, carcass gain, kill-out proportion, carcass conformation and carcass fat scores were 830, 811 and 859 (s.e. 14.9) g/day, 540, 533, 585 (s.e. 7.7) g/day, 526, 538 and 561 (s.e. 3.0) g/kg, 1.51, 2.18 and 2.96 (s.e. 0.085), and 3.40, 4.25 and 4.06 (s.e. 0.104) for HO, FR and CH, respectively. Corresponding values for pistola weight as a proportion of carcass weight, pistola muscle proportion and pistola fat proportion were 458, 459 and 461 (s.e. 2.6) g/kg, 657, 645 and 667 (s.e. 3.7) g/kg, and 132, 161 and 145 (s.e. 4.1) g/kg. Compared with the intensive system, animals on the extensive system had a lower (P < 0.001) daily live-weight gain, kill-out proportion and a lower muscle proportion in the pistola. Increasing slaughter weight increased (P < 0.001) carcass weight and carcass fat score and reduced the proportion of muscle in the pistola. Allometric regression coefficients for pistola weight on side weight, and total bone, muscle and fat weights on pistola weight were 0.898, 0.755, 0.900 and 1.910 respectively. It is concluded that HO grew at least as fast as FR but had a lower kill-out proportion. Carcass conformation and fat scores were greater for FR than for HO and muscle proportion in the pistola was lower and total fat proportion was higher. Compared with FR, CH had heavier carcasses, a higher kill-out proportion and less fat and more muscle in the pistola.

Keywords: Breed,carcass traits; cattle
†Corresponding author: gkeane@grange.teagasc.ie

The application of low crude protein wheat-soyabean diets to growing and finishing pigs

The application of low crude protein wheat-soyabean diets to growing and finishing pigs

Environmental aspects of soil phosphorus testing

Irish Journal of Agricultural and Food Research 44: 261–279, 2005

K. Daly^† and A. Casey

Teagasc, Johnstown Castle Research Centre, Wexford

Soil phosphorus testing in Ireland uses Morgan’s reagent from samples taken to 10 cm depth for agronomic recommendations. However, its suitability as an environmental indicator has been questioned in terms of sample depth and extraction solution. Seven grassland sites were sampled to depths of 2, 5 and 10 cm and extracted for Morgan’s P, the standard agronomic test, as well as iron-oxide impregnated paper strip P (FeO-P), calcium chloride extractable P (CaCl₂-P) and water soluble P (WSP), all proposed as environmental soil tests. Extractable soil P decreased with increasing sample depth, as did variances in each test, such that, 2 cm samples had highest concentrations and variances. The current standard sample depth (10 cm) was linearly related to corresponding data from samples taken to 2 and 5 cm, indicating that surface soil P can be consistently estimated from the current standard depth. When soil tests were compared with dissolved reactive P (DRP) in overland flow collected from two field sites, certain soil tests were better indicators of P loss than others. The relative difference in Morgan’s P values at the standard sample depth (10 cm) was reflected in the relative difference in P loss between the two sites. Average values of DRP collected from two sites ranged from 0.032 to 0.067 mg/l at the low P site and 0.261 to 0.620 at the high P site. Average DRP values from the high P site and maximum DRP values from the low P site were simulated using water-soluble P extraction at water to soil ratios 5 to 250 l/kg. In this study, Morgan’s P to 10 cm gave a good indication of the relative difference in DRP loss between the two sites.

Keywords: Environment; phosphorous; soil
†Corresponding author: Kdaly@johnstown.teagasc.ie

The phosphorus requirements for silage production on high fertility soils

Irish Journal of Agricultural and Food Research 44: 281–296, 2005

V. Power¹, H. Tunney^1† and D.W. Jeffrey²

¹Teagasc, Johnstown Castle Research Centre, Co. Wexford

²School of Botany, Trinity College, Dublin 2

The minimum phosphorus requirement for a mid-season ryegrass was investigated under cutting conditions over a 10-year period at each of three Teagasc sites (Clonroche, Johnstown Castle and Oak Park) in southeast Ireland. Treatments consisted of 0, 20, 30, 40, and 50 kg ha^–1 year^–1 P applied in autumn. Generally, there were three grass cuts each year and soil samples were taken after the third cut prior to the application of P. Nitrogen and potassium fertiliser was applied to ensure maximum grass yield. There was an emerging treatment effect over time as evidenced by the significance of the treatment ×year interaction. The effect of site varied with year reflecting the variability in weather and number of cuts taken at the individual sites. A treatment effect on annual first-cut-silage yield was observed. The largest treatment difference for dry matter (DM) yield of first-cut silage was between the control and the P treated plots (0.32 t/ha). The results show that the draw down of soil-P reserves was adequate to maintain yield for a number of years without additional fertiliser P application. Initial soil tests indicated moderate to high soil test P levels (STP) as measured by the Morgan’s test. Application of P at equivalent to removal rates did not maintain STP. The results suggest that application of a regular small maintenance dressing of P, replacing realistic removals, is the most appropriate fertiliser application strategy.

Keywords: Available P; phosphorus; P requirement; ryegrass
†Corresponding author: htunney@johnstown.teagasc.ie

A laboratory study of the effects of water dissolved gypsum application on hydraulic conductivity of saline-sodic soil under intermittent ponding conditions

Irish Journal of Agricultural and Food Research 44: 297–303, 2005

U. Sahin^† and O. Anapali

Ataturk University, Faculty of Agriculture, Department of Agriculture, Structures and Irrigation, 25240, Erzurum, Turkey

Reclamation of saline-sodic soils has great importance in agricultural management. The objective of this study was to evaluate the effectiveness of the methods used to apply water and gypsum on hydraulic conductivity of a saline-sodic soil with an electrical conductivity of 28 dS/m and exchangeable sodium percentage of 46%. The experiment was conducted under laboratory conditions using disturbed and non-cropped soil columns. A total of 45 cm of water was applied to each column with 3, 6, or 9 separate water applications. Finely ground gypsum (< 0.5 mm maximum particle diameter) was either incorporated into the surface 2 to 3 cm of soil or was dissolved into the leaching water at a rate corresponding to 3.82 t/ha. Six or nine separate water applications of gypsum dissolved into leaching water significantly increased hydraulic conductivity (P < 0.01). Soil hydraulic conductivity increased (P < 0.01) with depth at separate applications of gypsum.

Keywords: Gypsum; hydraulic conductivity; saline-sodic soil
†Corresponding author: ussahin@atauni.edu.tr