T. R. Batra's research while affiliated with University of Guelph and other places

Publications (14)

Article
Incidence of clinical mastitis in 821 lactations of Holstein line cows (H) and in 581 lactations of synthetic line cows derived from Ayrshire females (A) housed under intensive management was studied to examine effects of sire, parity, and month of calving. Ten traits were examined for each lactation of a cow: (1) number of separate quarter cases,...
Article
Incidence of clinical mastitis in 760 lactations of 331 Holstein cows was studied for effects of sire, parity, and month of calving. Incidence of clinical mastitis was higher in hind quarters than fore quarters. Positive correlations between number of cases in one quarter with number in other quarters and between proportion infected in one quarter...
Article
Forty-nine Holstein cows in first lacta- tion representing a wide range of esti- mated transmitting abilities were fed complete feeds ad libitum from calving to 305 days of lactation. Rations included equal parts (dry matter basis)of corn silage and hay crop silage mixed with sufficient concentrate to provide 60% of the digestible energy estimated...
Article
The objective was to relate the average herdmate milk deviation of cows which completed one or more records in each of two Canadian dairy herds. Record of Performance records of Canadian Holstein cows transferred at least once during their productive life were studied to evaluate the use of milk records in one herd to predict a cow’s production in...
Article
Full-text available
Procedures for estimating the breeding value for average daily gain of beef bulls across breed and across test groups are described. The estimates are best linear unbiased predictions taking into account breed, test group, paternal half-sibs and heritability. Breed differences based on Canadian test stations indicate that Angus gain approximately.0...
Article
Mammary gland histology and milk composition were studied in Holstein cows and heifers induced to lactate following 17β-estradiol and progesterone therapy for 7 days. The most notable gross histological observation was a large number of immature or developing ducts and alveoli. These ducts and alveoli were without lumen and consisted mainly of clum...
Article
Data consisted of 11 type appraisal traits for 51,044 Holstein first calf heif- ers with age at classification from 25 to 36 me. Effects of 10 rounds, 12 monthly ages at classification, 12 monthly stages of lactation, and 12 months (season) of classification were analyzed by least- squares. Effects of these four environ- mental factors were signifi...
Article
Full-text available
Fat thickness and longissimus muscle area were measured ultrasonically on 229 beef bulls on performance test. Charolais bulls were leaner than Hereford and Angus at both start and end of test and grew more quickly. Rate of gain on test was not related to initial age, weight or fat thickness, with partial correlations of.00,.22, and −.01, respective...
Article
Type records of 12,030 Canadian Hol- stein cows in first lactation with both sires and maternal grandsires in a group of 200 artificial insemination sires were analyzed to determine the importance of specific combining ability. Data were adjusted for effects of round of classifi- cation, age, stage, and season of classi- fication before final analy...
Article
The data were taken from 2,534 Holstein herds on Record of Performance (R.O.P.) for milk. Herd size was determined from the average inventory of cows on July 1, 1967 and July 1, 1968. Herd production was obtained for cows with records from March 1, 1967 to February 29, 1968. The cows disposed of from September 1, 1967 to August 31, 1968 were record...

Citations

... The variation in energetic efficiency between cows can arise from differences in digestion and utilization of ME for separate functions. Studies have indicated some differences among cows in their ability to digest a given diet (Trigg and Parr, 1981;Berry et al., 2007), whereas in the studies of Grieve et al. (1976) and Kennedy et al. (2003), no difference in the digestibility of diet between genetically high-and low-merit cows was found. On the other hand, in the study of Richardson and Herd (2004), lower REI (higher efficiency) values were associated with a greater digestibility. ...
... Rendel and Sundberg (1962) reported clinical mastitis incidence of 14.97o in first lactation compared to 37 .lVo in fourth lactation. Incidence of mastitis increases with age of cow (Braud and Schultz 1963;Miller et al. 1973;Batra 1979). Wesen et al. (1968) studied the relationship between the types ofbacteria isolated from a quarter and the CMT score of that quarter. ...
... (Tosh, 19921, a function of only heritability and contemporary group size. Wilton et al. (1975) presented a similar equation for performance-tested bulls that allowed for common sires. Curves derived from [61, inFigure 5, differ markedly from those inFigure 4 when contemporary groups contain few animals. If an individual was alone (i.e., n, = 1) and had no relatives, accuracy was zero. Estimation of fixed contemporary group effect ...
... In New Zealand, Dalton (1976) reported phenotypic correlations for start weight, final weight, start age, and test gain from earlier data of a similar type to the present data. His five values are shown in Table 7Warwick & Cartwright (1955)MooreStuedemann et al. (1968)Wilton et al. (1973)Brown & Keaton (1974)Rahnefeld, G. W.(1978; pers. comm.)Steane ...
... Even though a large herd effect on the risk of being culled has been mentioned by a few studies (Beaudeau et al., 1995;Emanuelson and Oltenacu, 1998;Gröhn et al., 1998), we could find only three studies that assessed the association between herd culling rates and some herdlevel management factors (Batra et al., 1971;Smith et al., 2000;Mohd Nor et al., 2014). While all three studies found a positive relationship between the culling rate and average herd production, the results were discordant regarding the association with herd size, from no effect (Batra et al., 1971), to increased cull rates in larger herds (Smith et al., 2000), or in smaller ones (Mohd Nor et al., 2014). ...
... Estimates of heritability of type traits (1,3,4,5,6,7,8,9,11,12,13,14,16,18,19,20,21,22,23,24,28,30) mostly are for Holstein-Friesian cattle. Much of this research was reviewed by White (27). ...
... Para aumentar a produção leiteira por meio da seleção de animais funcionais e produtivos é necessário identificar e quantificar os fatores de meio ambiente que influenciam as características consideradas na classificação linear para tipo. Estudos mostram que há influência dos fatores de meio como rebanho, ano e estação de classificação, estádio da lactação, idade ou ordem do parto, classificador, dentre outros, sobre as características lineares de tipo (Wilcox et al., 1959;Norman e Vanvleck, 1972a;Rennie et al., 1974;Thompson et al., 1983;Lawstuen et al., 1987). Lucas et al. (1984) e Funk et al. (1991) estudaram os efeitos de meio sobre as características de conformação em vacas da raça Holandesa, encontrando efeitos significativos da idade da vaca, do estádio da lactação e do classificador sobre algumas características de tipo. ...
... This has lu15-el1 bt'en lrehicrr'tl in stltti,rtt ld\l\. il\ ll \L'r) low phenotypic corre lation bc-trveen -qror',th rate on tcst anci startin-r $'ei-sht lfter uarm-ttp has been firund by Wilton et al. (1973) and Batra and Wilton (1972). Similar adjustment periods r'r ould bc nccessary tbr within-hcrd tests. ...
... It has been reported that the incidence of mastitis can increase in spring and summer (Sabuncu et al. 2013), the others reported that incidence of mastitis can increase in winter and autumn (Batra et al. 1977). Also, the effect of parity on SCC (Nguyen et al. 2011b;Sabuncu et al. 2013) and subclinical mastitis (Jarassaeng et al. 2012) has been shown. ...
... A evolução dos protocolos de indução está ilustrada naFig. 1.Narendran et al., 1974;Magliaro et al., 2004) e sobre a contagem de células somáticas (CCS;Magliaro et al., 2004;Freitas et al., 2010;Macrina et al., 2011b). Em um estudo realizado no Brasil, na ausência de um grupo controle (lactação natural), os dados obtidos quanto à porcentagem de proteína, gordura, lactose e sólidos totais estiveram de acordo com os valores de referência (Freitas et al., 2010). ...